Goldschmidt2013 Conference Abstracts 2435

Geochemistry and nano-structure of Clumped isotopes, " 18O, " 13C, " 11B, putative filamentous microbes from 87Sr/86Sr: A multiproxy approach the 3.24 Ga Sulfur Springs Group, applied to Silurian brachiopod shells Pilbara, Western Australia ULRIKE WACKER1, JENS FIEBIG1, AXEL GERDES1, 2 2 1,2 2 2 AXEL MUNNECKE , MICHAEL M. JOACHIMSKI D. WACEY *, M. SAUNDERS , M.R. KILBURN , 3 2 3 2 AND BERND R. SCHÖNE J.B. CLIFF , C. KONG , M.E. BARLEY AND D. N. MCLOUGHLIN1 1Department of Geosciences, Goethe University Frankfurt, 1 Germany ([email protected]; University of Bergen, Bergen N-5007, Norway [email protected]; [email protected] (*correspondence: [email protected]) 2 frankfurt.de) University of Western Australia, WA 6009, Australia 2 3 GeoZentrumNordbayern, FAU Erlangen-Nürnberg, Germany University of New South Wales, NSW 2052, Australia ([email protected]; [email protected]) Pyritic filaments from one of Earth’s oldest volcanic 3Institute of Earth Sciences, Johannes Gutenberg-University, hosted massive sulfide (VHMS) deposits within the 3.24Ga Mainz, Germany ([email protected]) Sulfur Springs Group, Western Australia, have been

interpreted as thermophilic chemotrophic micro-organisms The geochemical composition of fossil brachiopod shells [1]. This interpretation [1] was based upon textural, reveals information about physical and chemical conditions of morphological and inferred behavorial characteristics of the the paleo-ocean. We studied different stable isotopic systems filaments. However, no geochemical evidence for biology has on Silurian brachiopod shells from Gotland/Sweden to test yet been reported, so an alternative explanation as abiotic their resistance against diagenesis and their use for mineral filaments remains to be discounted. paleoreconstructions. Here we revisit these putative filamentous micro- In general, preanalyses (CL, SEM and trace element organisms, using a suite of high-spatial resolution techniques concentrations) of more than 60 shells indicate very good to investigate their geochemistry and nano-structure. preservation. However, SEM investigations show that partial NanoSIMS elemental mapping reveals occassional recrystallization occurred resulting in a patchwork of pristine enrichments of carbon within some of the pyritic filaments. and altered structures. "18O and "13C, clumped isotope (! ), as Similar patterns of carbon enrichment are seen in bona fide 47 well as high resolution (LA-(MC)-ICP-MS) "11B and 87Sr/86Sr pyritic filamentous microfossils from the 1.9 Ga Gunflint chert data of several brachiopod shells and their inner fillings that were also pyritised by hydrothermal fluids. (mudstones and sparitic cements) were measured. Clumped In situ SIMS multiple sulfur isotope data show small but 33 36 isotope temperatures range from 30°C to 70°C, indicating, that significant +! S (and –! S) anomalies, consistent with ! values were partly reset during diagenesis. Because highest previous bulk data from this VHMS deposit [2], indicating 47 shell alteration temperatures correspond to those measured for mixing of a hydrothermal fluid containing sulfur of magmatic 13 18 33 the cements, we propose that C- O clumps were reset during origin (! S=0) with circulating seawater containing reduced 18 33 cement formation. Since no correlation between ! and " O sulfur derived from atmospheric elemental sulfur (+! S). 47 values is obtained, we conclude that the bulk oxygen isotopic The nano-structure of the filaments was investigated in the composition was not altered concurrently. Furthermore, "11B TEM using focused ion beam (FIB)-milled ultrathin sections, and 87Sr/86Sr values of the brachiopods seem to reflect pristine and by 3D FIB-SEM nanotomography. Notable features marine signatures. Therefore we suggest that the alteration of include circular to elliptical filament cross sections mostly clumped isotope values occurred at low water-rock ratios, not comprising single pyrite crystals, clustering of filaments in influencing "18O, "13C, "11B and 87Sr/86Sr signals. pairs and triplets, and a common preferred orientation of many filaments. These data provide new insights into one of Earth’s oldest black-smoker-type environments and potential associated life. The strength of evidence for the biogenicity of the filaments will be discussed.

[1] Rasmussen (2000) Nature 405, 676-679. [2] Golding et al. (2011) in Earliest Life on Earth: Habitats, Environments and Methods of Detection, pp. 15-49.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2436 Goldschmidt2013 Conference Abstracts

B-isotope variations in tourmaline in Speleothem reconstruction of sea- the Varuträsk rare-element level at Bermuda over the last pegmatite: the role of mica climatic cycles THOMAS WAGNER1, ROBERT. B. TRUMBULL2*, KARIN K. WAINER1*, G.M. HENDERSON1, A.J. MASON1, SIEGEL3, ERIK JONSSON4 AND CHRISTOPH A. HEINRICH5 A.L. THOMAS1, M. ROWE2, B. WILLIAMS3, 4 4 1 P. J. VAN HENGSTUM AND R. CHANDLER Division of Geology, University of Helsinki, Finland 2GFZ German Research Centre for Geosciences Potsdam 1Dept. of Earth Sciences, Oxford University, South Parks Germany (*presenting: [email protected]) Road, Oxford OX1 3AN, United Kingdom 3Earth & Planetary Sciences, McGill University, Canada (*correspondence: [email protected]) 2 4Earth Sciences, Uppsala University, Sweden Birkbeck College, malet street, London WC1E7HX, 5Earth Sciences, ETH Zürich, Switzerland UK 3Bermuda Institute of Ocean Sciences, St George’s, Bermuda The Varuträsk rare-element pegmatite in northern Sweden is a 4Woods Hole Oceanographic Institute, Massachusetts, USA classic and typical example of highly fractionated LCT-type 5Bermuda Zoological Society, Bermuda pegmatites, with a well-developed internal zoning pattern composed of border, wall and intermediate zones and a quartz It is now widely accepted that a sea-level rise is associated core. Major and trace element fractionation trends of with global warming [1]. However, its rate, and the height it feldspars, micas, tourmaline, and columbite-tantalite correlate might reach by the end of the century remain poorly well with the internal zoning pattern. This pegmatite therefore constrained. This study aims to provide better information and forms a good basis for a case study on the use of boron precision on the rates and magnitudes of past sea-level change, isotopes in tourmaline to record processes of pegmatite for periods when sea-level is close to its modern value, using internal evolution. speleothems from Bermudian caves. Speleothems interrupt Early and mid-stage tourmalines from Varuträsk show a their growth when they are submerged by sea-water, so U-Th 11 systematic increase in ! B values from -14.6 to -6.2 ‰ during dating periods of growth in coastal sites allows the crystallization of the primary pegmatite zones. This trend reconstruction of past sea-level variation versus absolute time 11 toward B-enrichment in the pegmatite magma is opposite to [e.g. 2,3,4]. We will present new MC-ICP-MS U-Th ages that expected for fluid exsolution or progressive crystallization from a set of speleothems (stalagmites, stalactites, flowstones) of tourmaline, and all geochemical and textural evidence collected from -6 to +12 m versus modern sea level from suggests a closed-system crystallization without significant several caves in this northern Atlantic archipelago. influx of external fluids with heavy B-isotope signature. We Relative sea-level (RSL) at Bermuda is of particular suggest that crystallization of abundant muscovite in the interest because it is at a distance from northern hemisphere 10 Varuträsk wall zone depleted the magma in B, driving the ice sheets where the isostatic response to ice-unloading is 11 residual melt toward higher ! B values. Rayleigh uncertain. RSL reconstruction therefore provides both an fractionation models based on measured B contents of 220 indicates of possible rates of sea level change, and a test for ppm in muscovite and 3.4 wt. % in tourmaline show that the glacial-isostatic-adjustment (GIA) models. muscovite/tourmaline mass ratio required to explain the Our results provide constraint on sea level over the last 11 observed shift in ! B values is about 200:1, which is climatic cycles, and in particular periods when sea level was consistent with the modal composition of the wall zone equivalent or higher than today, at Bermuda which we place in assemblage. the context of previous assessments of eustatic change, and of The assumption is commonly made that in rocks where GIA models. tourmaline is present, it plays the dominant role in B-isotope evolution. This assumption is likely to be true for most [1] Intergovernmental Panel on Climate Change (2007) crystalline rocks but our study shows that it may not be the Contribution of Working Group I to the Fourth Assessment case for assemblages with a high modal abundance of micas, Report, Cambridge Univ. Press. [2] Harmon et al. (1981) as in many pegmatites and related rocks such as greisens. Nature 289, 357-360. [3] Richards et al. (1994) Nature 367, 481-483. [4] Bard (2002) EPSL 196, 135-146.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2437

Sulfide Re-Os Dating in Modally The Role of Reactive Intermediates in Metasomatised Peridotites, Insights Redox Transformations of Iron in from Letlhakane (Botswana) Photolyzed Acidic Natural Organic A.N. WAINWRIGHT,*1 A. LUGUET1, R.O.C. FONSECA1 Matter Solutions 2 AND D.G. PEARSON 1 1 1 T. DAVID WAITE, SHIKA GARG, MARK L. BLIGH AND 1 Steinmann Institut, Universität Bonn, Germany ANDREW L. ROSE2 *correspondence: ([email protected]) 1 School of Civil & Environmental Engineering, The 2Department of Earth and Atmospheric Sciences, University of University of New South Wales, Sydney; Alberta, Edmonton, Canada [email protected] 2 Southern Cross Geosciences, Southen Cross University, Mantle xenoliths are a geochemist’s window into the Lismore; [email protected] chemical and mineralogical make-up of the sub continental lithospheric mantle. However, metasomatism can obscure the primary composition and melt depletion history of the Recent studies of the dark oxidation of Fe(II) in previously xenoliths. Therefore, whole-rock Re-Os age analysis of photolysed acidic solutions of natural organic matter (NOM) peridotite xenoliths may provide only a minimum estimate for (Garg et al. [1]) suggest the superoxide-mediated formation the age of the lithospheric mantle, and likely reflects the of semiquinone radicals which act as effective oxidants of presence of multiple generations of base metal sulfides (BMS) Fe(II) (Schematic 1). or platinum group minerals (PGM), which differ in age as well as mineralogy and habit. While metasomatic sulphides and/or PGM are likely to yield ’artificially young‘ Re-Os ages, refractory PGM such as Os-Ir-Ru alloys and refractory sulphides (e.g. laurite) should preserve older ages as a result of their high Os concentrations and resilience to overprinting and isotopic resetting. Together they provide the perfect target to investigate the Os isotopic heterogeneity in mantle samples. Peridotite xenoliths found associated with the Letlhakane kimberlite (Magondi Belt, Botswana) provide us with a unique opportunity to study modal metasomatic effects on Re-Os and

PGE systematics [1]. Whole rock analysis of xenolith samples Schematic 1. Photolysis of NOM generates HO2* which, 2- from Letlhakane show co-variations of Re-Os TRD ages and in turn, oxidize hydroquinone species (A ) present in NOM to - highly siderophile element fractionations (e.g. Pd/Ir: 0.1, TRD: semiquinone radicals (A ). These radicals are effective

2.7Ga – Pd/Ir 1.69, TRD 1.6Ga), due to variable degrees of oxidants for low concentrations of Fe(II). After Garg et al. [1] metasomatic overprint. Three samples that cover the entire metasomatic range were chosen to measure single grain In comparison, on continuous photolysis, light-generated sulfides for Re-Os via micro-distillation. Preliminary results singlet oxygen appears to oxidise A- to the quinone form (A)

show a wide range in sulfide TRD ages, from future ages to with short-lived organoperoxy radicals (ROO*) capable of over 3.0 Ga, even in the most metasomatised sample. The oxidizing Fe(II) (Garg et al. [2]). habit and structure of the sulfide seems to be the most important factor. Disseminated sulfides occuring in veinlets [1] Garg, S., Ito, H., Rose, A.L. and Waite, T.D. (2013). have the youngest age and most radiogenic 187Os/188Os. On the Environ. Sci. Technol. 47, 1861!1869. [2] Garg, S., Jiang, C., other hand, discrete interstitial sulfides exhibit unradiogenic Rose, A.L. and Waite, T.D. Environ. Sci. Technol. (submitted 187Os and Archean ages. Our preliminary findings stress the March 2013). micro-scale heterogeneity of Os isotopic signatures, which likely reflects mulitple host mineral generations whose origins are linked to the complex multi-event petrogenetic history of mantle samples.

[1] Stiefenhofer et al. (1997) Contrib. Mineral Petrol. 127, 147-158.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2438 Goldschmidt2013 Conference Abstracts

Stable isotopic fractionation of Sr and Anisotropy: A cause of heat flux Eu among igneous rocks variation at the CMB? S. WAKAKI123, M. TANIMIZU1, T. ISHIKAWA1 ANDREW M. WALKER*1, MICHAEL W. AMMANN2, AND T. TANAKA3 STEPHEN STACKHOUSE3, JAMES WOOKEY1, JOHN P. 2 2 1 BRODHOLT AND DAVID P. DOBSON Kochi Institute for Core Sample Research, JAMSTEC, Kochi 783-8502, Japan. (wakaki(at)jamstec.go,jp) 1School of Earth Sciences, University of Bristol, Wills 2Natural History Sciences, Hokkaido Univ., Japan. Memorial Building, Queen's Road, Bristol BS8 1RJ, UK 3Earth Environmental Sci., Nagoya Univ., Japan. (* correspondence: [email protected]) 2Department of Earth Sciences, University College London, Sub-permil isotopic variations of Mg, Si, Fe and Sr were Gower Street, London WC1E 6BT, UK observed among igneous rocks, and the possibillity of high 3School of Earth and Environment, University of Leeds, Leeds temperature isotope fractionation during magmatic processes LS2 9JT, UK have been documented (e.g.; Charlier et al. , 2012; Savage et al. , 2011; Teng et al. , 2007; Teng et al. , 2008). We report We have used atomic scale simulations to determine the

sub-permil to permil order stable isotopic variation of Sr and thermal conductivity of MgSiO3 perovskite and post- Eu among igneous rocks with various origins. perovskite under D"" conditions and shown that the thermal 28 igneous rocks covering a wide range of chemical conductivity of post-perovskite (!12 W/mK) is 50% larger

compositions (SiO2 = 46.7 - 78.2 wt.%) were analyzed. than that of perovskite under the same conditions (!8.5

Samples were decomposed with a mixture of HF, HNO3 and W/mK). This finding, in agreement with previous studies on

HClO4. Granite samples were processed using Teflon bombs. analogue materials, means that the high heat flux into cold Sr was separated by extraction chromatography using Sr Spec regions of D"" where post-perovskite is stable is enhanced resin (Eichrom). Eu was separated by cation exchange column relative to a simple single-phase case [1]. Furthermore, we chromatography using AG 50W-x8 (Bio-Rad) with HCl and have found that the thermal conductivity of post-perovskite is !-HIBA. Stable isotopic composition of Sr was analyzed by anisotropic, with conductivity along the a-axis being 40% DS-TIMS technique using 84Sr-86Sr double spike and VG higher than conductivity along the c-axis. Thus, – similarly to Sector 54-30 at NU. The results are expressed with relative to the lithosphere [2] – there is potential for texturing caused by 88 88 86 88 86 3 NBS 987 as " Sr = [( Sr/ Sr)sample/( Sr/ Sr)NBS 987 – 1] x 10 . deformation to modify how the mantle is heated from below. The reproducibility of "88Sr was ± 0.06. Stable isotopic We test this idea by coupling our atomic scale results to composition of Eu was analyzed on the Thermo Neptune MC- previous models of texture in D"" [3] and find that anisotropic ICP-MS at JAMSTEC with external normalization using Sm. thermal conductivity may help to stabilise the roots of mantle Potential isobaric interference of BaO was checked and found plumes (Figure 1). to be neglegible. The results are expressed with relative to an 153 153 151 Alfa Aesar Eu2O3 reagent as # Eu = [( Eu/ Eu)sample 153 151 4 153 /( Eu/ Eu)STD – 1] x 10 . The reproducibility of # Eu was ± 0.31. The "88Sr and #153Eu of the mafic and intermediate samples agreed each other with an average of +0.27 and +0.13, respectively. Felsic samples showed significantly large variations both on "88Sr and #153Eu ranging from +0.36 to - 0.99 and from +0.20 to -5.73, respectively. Our "88Sr results for six international reference rocks agree well with the previously reported values. The observed variations of both Figure 1: Modelled CMB heat flux at the base of a large "88Sr and #153Eu are correlated with SiO abundances and also 2 plume in the East Pacific. Compared to the isotropic case (a) with the magnitude of negative Eu anomaly. The correlation the horizontal heat flux in the anisotropic textured case (b) between "88Sr and #153Eu with negative Eu anomaly indicates feeds heat, and thus boyancy, into the plume. that the variation of "88Sr and #153Eu was caused by

plagioclase fractionation during magmatic differentiation [1] Hunt et al. (2012) EPSL 319-320, 96–105. [2] Tommasi et processes. This observation suggests that the melt-plagioclase al. (2001) Nature 411, 783-786. [3] Walker et al. (2011) isotope fractionation factor (!-1) of Sr and Eu at magmatic Geochemistry Geophysics Geosystems 12, Q10006. temperature is on the order of 10-4.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2439

New Constraints on the Magnitude A first principles study of uranyl and and Timing of Late Accretion neptunyl incorporation into sulfate RICHARD J. WALKER1*, MATHIEU TOUBOUL1, IGOR S. minerals PUCHTEL1 AND JINGAO LIU2 S. M. WALKER* AND U. BECKER 1Dept. of Geology, Univ. of Maryland, College Park, MD Earth and Environmental Sciences, University of Michigan, 20742, USA (correspondence: [email protected]) 2Department of Earth & Atmospheric Sciences, Univ. of 2534 CC Little, Ann Arbor, MI 48109, USA (*correspondence: [email protected]) Alberta, Edmonton, Alberta, Canada

Solid solution formation at the mineral/water interface Late accretion is defined as continued planetary growth occurs when an ion in solution replaces an ion in the lattice; subsequent to the cessation of core segregation. Late accretion however, experimental observations have not fully decoupled was evidently a common, final step in the formation histories the factors that control this process (e.g. ionic radius of foreign of rocky planetary bodies, regardless of size [1]. Evidence for ion, coordination environment, molecular orbital interactions, this comes from estimates of planetary mantle compositions charge compensation). In order to examine the for various bodies, projected to contain raised, and broadly thermodynamics of incorporation, the energies of chondritic relative abundances of the highly siderophile incorporation of uranyl (UO 2+) into anhydrous sulfate elements (HSE). Although a ubiquitous process, the 2 minerals, anglesite (PbSO ), barite (BaSO ), and celestine proportions of late accretionary mass additions, relative to 4 4 (SrSO ), are calculated using a quantum mechanical approach. planetary mass, may have ranged considerably. For example, 4 For each mineral, source and sink reference phases are chosen current estimates suggest the Earth and Mars received to facilitate the substitution of the uranyl ion with a cation proportionally much more late accreted mass than the Moon, from the host mineral as described by the general equation: perhaps reflecting stochastic late accretionary processes [2].

The timing of late accretion must also have varied host mineral + U source # UO 2+ mineral phase + sink considerably, with late accretion evidently occurring on 2 solid UO solid (Pb,Ba,Sr)O asteroidal-sized bodies within the first 10 m.y. of solar system 3 UO 2+ (aqueous complex) (Pb,Ba,Sr)2+ (aq. complex) formation [1], but also acting on late-formed bodies, such as 2

the Moon. Of the three sulfate minerals, the energy of uranyl The nature and timing of late accretion to Earth is a incorporation into anglesite was the lowest for solid state particularly important issue, as this process could have oxide reference phases (!E = 1.57 eV). Anglesite also delivered considerable water and organics to the mantle. One rxn provided the lowest energy of incorporation of an aqueous possibility is that the putative giant impact that generated the species (UO 2+ with the release of Pb2+ ). Using aqueous Moon was a major clearinghouse event for HSE, and thus, an 2 aq aq species as source and sink phases but solid incorporation hosts event that heralded in a final stage of terrestrial late accretion. required the combination of periodic and cluster quantum The long-term preservation of 182W isotopic heterogeneities in mechanical methods. Incorporation of uranyl was then the mantle [3-4], however, likely indicates that the terrestrial compared with incorporation of Np(VI)O 2+ and Np(V)O + mantle was never completely homogenized, and possibly that 2 2 aqueous neptunyl complexes. the cumulative effects of terrestrial late accretion commensed Since these static incorporation energies are most closely well before the Moon-forming event. The presence of small 182 representative of the enthalpy of incorporation, the free energy enrichments in W in some early-Earth rocks (Isua [3] and was estimated using vibrational entropy values from empirical Nuvvuagittuq), coupled with depletions in HSE abundances force field calculations in order to curtail computational estimated for their mantle sources, provides some evidence for expense. These vibrational entropy data tend to make uneven mixing of late accreted materials into the mantle, incorporation energy values less energetically uphill. The although other options to explain the enrichments are also 182 limits of U- and Np-incorporation were also calculated to possible. Of note, the magnitudes of W enrichments are predict solid solution behavior. consistent with the mass addition proportions suggested by HSE abundances [3].

[1] Day et al. (2012) Nature Geoscience 5, 614-617, [2] Bottke et al. (2010) Science 330, 1527-1530, [3] Willbold et al. (2011) Nature 477, 195-198, [4] Touboul et al. (2012) Science 335, 1065-1069.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2440 Goldschmidt2013 Conference Abstracts

The geochemisty and mineralogy of Liquid-liquid separation at the onset responsible mining of rare earths. of CaCO3 formation FRANCES WALL1 A.F. WALLACE1, 2*, L.O. HEDGES1, 2, 1, 3 4 1 A. FERNANDEZ-MARTINEZ , P. RAITERI , Camborne School of Mines, University of Exeter, Cornwall S. WHITELAM2, G.A. WAYCHUNAS1, J.D. GALE4,, Campus, Penryn, TR10 9EZ, UK. [email protected] 1, 5 2,6 J.F. BANFIELD AND J.J. DE YOREO Responsible mining is often regarded as largely a socio- 1Earth Sciences Division, Lawrence Berkeley National economic issue but although good behaviour and governance Laboratory, Berkeley, CA 94720, USA (*correspondence: are important, the fundamental ore deposit geochemistry and [email protected], [email protected]) mineralogy also influence many relevant factors. For example, 2The Molecular Foundry, Lawrence Berkeley National energy use, water use, resource efficiency, financial Laboratory, Berkeley, CA 94720, USA profitability, potential environmental contamination, and the ([email protected], [email protected]) health, safety and well-being of the work force are all related 3ISTerre, CNRS & Université de Grenoble 1, 38041 Grenoble, to the minerals present; to their compositions, sizes, shapes, France ([email protected]) textural relations, solubilities, amenability to various 4Nanochemistry Research Institute, Department of Chemistry, beneficiation methods, and how strongly thery are held Curtin University, Perth, WA 6845, Australia together. ([email protected], [email protected]) Rare earths, used in many green technologies, are 5Department of Earth and Planetary Science, University of particulary interesting to consider from this point of view. California, Berkeley, CA 94720, USA Following the recent supply problems and the designation of ([email protected]) ([email protected]) rare earths as ‘critical’ metals, a wide range of rare earth 6Pacific Northwest National Laboratory, Richland, WA 99352 deposits are now under active exploration and development, ([email protected]) ranging from fresh and weathered carbonatites and alkaline rocks, to beach sands, ion adsorption clays and even sea floor Recent experimental characterizations of the early stages muds. These divserse deposits have have large differences in of calcium carbonate crystallization reveal an abundance of the characterisitcs listed above and raise a question about nanometer-sized prenucleation clusters that appear prior to whether some deposits are inherently more environmental- formation of an amorphous intermediate phase. The prevailing friendly that others. interpretation of the clusters as thermodynamically stable For example, unconsolidated beach sands, such as those suggests that the nucleation of calcium carbonate may follow a currently mined for monazite in India, do not need non-classical pathway. comminution and thus can require one third of the energy to This research uses replica-exchange molecular dynamics process than a hard rock carbonatite deposit. However, the techniques to probe the initial formation and onset of order monazite in beach sands is mostly derived from granitic within hydrated calcium carbonate cluster species and lattice

protoliths and contains typically several wt% ThO2, making it gas simulations to explore the more general behavior of radioactive and problematic to store, ship and process. In clusters during phase separation. A two-phase thermodynamic contrast, rare earth fluorcarbonates in carbonatite deposits model is also used to determine the free energy of the clusters have some of the lowest Th contents of any of the rare earth as a function of size and to enable comparison with classical minerals, and carbonatite monazite is also characteristically nucleation theory. low in Th. The results suggest that a spontaneous liquid-liquid phase In order to make comparisons, metrics are required and it separation may occur within the range of concentrations for is neccessary to balance the various factors, such as energy which pre-nucleation clusters are observed. Coalescence of the use, versus the other environmental impacts. The system of nanoscale droplets results in the formation of a phase whose apportionment of these impacts when the REE are by-products structure is consistent with that of amorphous calcium also makes a large difference to the outcome. Mineral carbonate. The significance of these results is discussed within compositions and associations do vary within each deposit the context of classical and emerging non-classical phase- type and it is possible to develop a geometallurgical approach separation theories. to environmental impact early on in an REE exploration project.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2441

The potential of using a sector field Magma formation in hot-slab ICP-MS for analysis of fluid subduction zones: Insights from inclusions by laser ablation ICP-MS volatile contents of melt inclusions M. WÄLLE* AND C.A. HEINRICH from the southern Cascade arc ETH Zurich, Inst. of Geochemistry and Petrology, WALOWSKI, K.J. 1, WALLACE, P.J. 1, CLYNNE, M.A. 2, Clausiusstrasse 25, 8092 Zurich, Switzerland, WADA, I. 3 AND RASMUSSEN, D.J. 1 (*correspondence: [email protected]) 1 University of Oregon, Eugene, Oregon 97403, USA

(correspondence: [email protected]) Laser ablation inductively coupled plasma mass 2USGS Volcano Science Center, Menlo Park, CA, USA spectrometry (LA-ICPMS) is a successful technique to 3 Tohoku University, IRIDeS, Sendai 980-8579, Japan measure elemental concentrations in fluid inclusions [1]. Depending on their salinity, inclusions in the size a 10 to Cross-arc geochemical variations can provide insight into several tens of micrometres are needed to determine trace dehydration reactions in the subducting slab and magma element concentrations reliably. Up to now, quardupole (Q-) generation processes in the mantle wedge. In this study, cinder ICP-MS have been used for this kind of analyses due to its cones were sampled at varying distances from the trench in the ability to switch fast (e.g. within one millisecond) from one Lassen Region, the southern segment of the Cascade Arc, mass to another over the entire elemental mass range. Short which subducts some of the youngest oceanic crust globally. settling times are required to record the fast changing transient Olivine-hosted melt inclusions (Fo84-90) from the tephra of 6 signals obtained by LA-ICPMS analyses of fluid inclusions. calc-alkaline basaltic cinder cones have been analyzed for Sector field (SF-)ICP-MS would provide a higher sensitivity volatile, major and trace elements. than Q-ICPMS and, therefore, have to potential to measure Using the maximum volatile contents at each cone to smaller inclusion, demand a higher settling time than the latter represent the undegassed magma, we find values (2.1-3.4 wt% ones due to changing the magnetic field. H O and 500-1200 ppm CO corrected to be in eq. with Fo90 A fast scanning SF-ICPMS was used to explore the 2 2, olivine), slightly higher than primitive melt inclusions from potential of this instrument for analysing fluid inclusions. An central Oregon [1]. These values from the Cascades overlap assemblage consisting of fluid inclusions in the range of a few with data for other arcs, but are lower on average. We have micrometres up to 150 µm and a salinity of 4wt% NaCl was also analyzed fluid-mobile trace elements to understand the used to (i) check the accuracy of the fast scanning SF-ICPMS trace element signature of the slab component and the extent system and (ii) compare the performance of a Q-ICPMS of fluid-fluxing across the arc. At the arc axis, (Sr/P) values (PerkinElemer, Elan 6100 DRC) and a SF-ICPMS N are high, although variable, and they decrease towards the (ThermoFisher, Element XR) coupled to the same laser backarc [2]. (Sr/P) correlates with other slab-derived fluid ablation system. The fast scanning SF-ICPMS system was N tracers such as H O/Ce and Cl/Nb, indicating a link between able to analyse fluid inclusions with a 1.8 to 2 times smaller 2 volatile and trace element enrichment of the mantle wedge. diameter, i.e. 5 to 8 times in mass, with a similar accuracy, e.g. Slab surface temperatures calculated using the H O/Ce on elements like Pb, Ba, Sb or Mg, than the Q-ICPMS system 2 thermometer [3] range from 740-870±50°C, which is slightly measuring the same elements. lower than those predicted by new 2D geodynamic models for

this region (850-950°C). The similarity of the temperature [1] Heinrich et al. (2003), Geochim. Cosmochim. Acta estimates suggests active fluxing of hydrous material from the 67, 3473-3496. slab into the mantle wedge beneath the arc rather than downdragging of hydrous mantle from the forearc region.

Both H2O/Ce and geodynamic model temperatures are at or

above the MORB+H2O solidus [4] suggesting the likelihood of hydrous slab melting beneath the arc. Because high slab temperatures require the slab to largely dehydrate beneath the forearc, our results require either substantial metastability of hydrous phases in altered oceanic crust or serpentinite-derived water from the mantle of the downgoing slab.

[1] Ruscitto(2010) EPSL 298, 153–161. [2] Borg (1997) Can. Min. 35, 425-452. [3] Cooper (2012) G3 13, (3). [4] Schmidt (1998) EPSL 163, 361–379.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2442 Goldschmidt2013 Conference Abstracts

World’s oldest eclogites? Diamonds and their inclusions from Phase equilibria constraints on 2 Ga Dachine, French Guiana: A record of metapelitic-hosted eclogites from the Paleoproterozoic subduction Usagaran Orogen, Tanzania M.J. WALTER *1, C.B. SMITH1, G.P. BULANOVA1, 2 1 1 1 1 S. MIKHAIL AND S.C. KOHN ALEC WALSH* , MARTIN HAND , ALAN COLLINS AND RACHEL BRICK1 1School of Earth Sciences, University of Bristol, Bristol, BS8

1 1RJ (*correspondence: m.j. walter @bristol.ac.uk) Centre for Tectonics Resources and Exploration, School of 2Geophysical Laboratory, Carnegie Institution of Washington, Earth and Environmental Sciences, University of Washington D.C. 20015, USA Adelaide, Adelaide 5005, South Australia, Australia

(correspondence: [email protected]) Diamonds and their mineral inclusions provide a record of deep mantle processes. Most diamonds are from the sub- Eclogite-facies rocks preserve a record of deep crustal continental mantle lithosphere and record ancient episodes of thickening and exhumation. Orogenic belts that contain growth, whereas others form at sub-lithospheric depths and eclogites generally mark plate collisions and are considered to record deep carbon cycling1. We report new data from a represent ancient subduction zones. Eclogites from the unique suite of diamonds and syngenetic inclusions from the Paleoproterozoic Usagaran Orogen, which flanks the eastern Dachine ultramafic, French Guiana. These samples defy margin of the Archean Tanzania Craton, yield ages of 2 Ga categorisation into traditional diamond groups, but show and are considered to be the amongst the oldest preserved evidence of originating in a subduction zone environment. eclogites in the world. The highly altered Dachine host rock (2.1 Ga) is not Phase equilibria constraints indicate that metapelitic rocks, kimberlitic, but based on textures and chemical characteristics which structurally envelop eclogite-facies mafic rocks [1], has been identified as a pyroclastic komatiite2. Dachine developed a peak metamorphic assemblage of gt–ky–amph– diamonds also have unique characteristics3 including low N mus–bi–ru–q at ~12 kbar and 650ºC; far lower pressures than aggregation state (type Ib), a predominance of light C and previously predicted. Prograde chemical zoning preserved in heavy N isotopes, and complex internal morphologies often garnet appears to mitigate against exhumation of the showing evidence of deformation. We have located five metapelites from eclogite facies conditions Rather, the syngenetic garnet and Cpx inclusions, which are the first petrological and compositional data suggest a steep up- reported silicate inclusions in Dachine diamonds. The three pressure prograde path. Premlinary data suggests that the garnet inclusions are eclogitic having high Ca and low Cr, and mafic eclogites underwent metamorphic reworking at around are unusually rich in Mn and Ni but extremely depleted in LIL the conditions recorded by the peak assemblages in the and LREE. The Cpx inclusions are also extremely depleted in enclosing metapelites. If this is correct is implies that the incompatible elements and one is Mn-rich. exhuming eclogites became structually mixed with The trace element systematics of the silicate inclusions are metasedimetary lithologies located higher in the exhumation best matched if the inclusions represent residual phases to channel. Such a scenario is similar to that inferred in modern either multiple melt/fluid extraction events during subduction, convergent margin settings, and implies that the Usagaran or by a single extraction event involvimg coexisting trace Orogen is one of the oldest examples of “modern style” plate phases such as epidote and rutile. Temperature constraints margin metamorphism. from N aggregation are inconsistent with a high-temperature komatiite origin for the Dachine host, whereas trace element [1] Möller, Andreas, et al. "Evidence for a 2 Ga subduction systematics can be reconciled with a melt generated in a zone: Eclogites in the Usagaran belt of subduction zone environment, an origin which we presume is Tanzania." Geology 23.12 (1995): 1067-1070. cold and hydrous. A model integrating all these observation suggests diamond and inclusion growth, and possibly host magma generation, at the interface between a Paleo- proterozoic subducting slab and overlying mantle.

[1]. Shirey et al (2013), RIMG 75, 355-421. [2]. Capdevila et al (1999), Nature 399, 456-458. [3]. Cartigny et al (2010) EPSL 296, 329-339.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2443

New insights on gas storage and Use of sulfur isotopes to quantify transport in shales biological and abiotic processes CLIFFORD C. WALTERS1 contributing to sulfur cycling in an 1ExxonMobil Research & Engineering, 1545 Rt. 22 E, AMD treatment system Annandale, NJ 08801. 1 2 EVAN R. WALTERS , CHARLES W. PUGH [email protected] 2 1, KELLY S. BENDER AND LILIANA LEFTICARIU *

The rapid development of shale gas and liquids has far 1Southern Illinois University, Department of Geology, outpaced our knowledge of how these systems function. Most [email protected]; [email protected] (*presenting author) of the tools and models used on conventional reservoirs are 2 Southern Illinois University, Department of Microbiology, inadequate to characterize tight rocks. Using new methods [email protected]; [email protected] and techniques, researchers in industry, academia, and government labs have made considerable progress in revealing Untreated drainages from abandoned coal mines are the underlying processes involved in gas storage and transport. generally low-pH waters that contain high concentrations of 2- Although all shales have some inter- and intra-granular dissolved SO4 , Fe, Al, Mn and other elements of mineral porosity, the majority of the gas in mature, carbon- environmental concern (e.g., As, Se, Zn, Cd and Ni). In the rich shales is stored in porous organic matter. NMR, small Illinois Basin this has been a significant and costly problem as angle neutron scattering (SANS), mercury injection capillary extensive mining has been carried out during the last century. pressure (MICP) and gas sorption experiments suggest that Currently, treatment systems of coal-generated AMD include 2- shales possess a broad range of pore sizes with an appreciable the use of bio-induced stabilization of dissolved SO4 and volume existing in mesopores having diameters of 2 to 50 nm. metals in sulfides, as the optimal way for effective, long-term Unlike conventional reservoirs where pore throats tend to treatment. However as AMD systems evolve, fluctuations in scale with pore size, the connecting pore throats in shales physical (e.g., rain induced-dilution, dynamic AMD flow appear to be small (<20 nm). SEM has been extensively used rates), chemical (e.g., precipitation, sorption, desorption, etc.) to image pores in shales, but sees only a fraction of the pore and biological processes provoke temporal disequilibra within network. The Zeiss Helium Ion Microscope has proven to be the system. Therefore, it remains challenging to assess the capable of imaging the nm-scale structures revealing the the extent of permanent contaminant sequestration and predict true nature of gas storage in shales. Local porosity in kerogen long-term treatment viability. can be extremely highly (>30%) and nm-wide conduits for gas We present a 1-year study of concentrations and "34S migration can be traces over µm distances. These porous values of sulfur compounds in six field-scale column networks form late in the oil window, becomes abundant by experiments conducted at the Tab-Simco site to constrain the the onset of the gas window, and remain relatively unaltered in efficiency of various organic substrates in supporting the bio- shales at extremely high maturity. reduction processes. Our results show: (1) During warm The nm-scaled features, however, are inadaquet to explain months months (T > 10 °C) high levels in H2S in the reactors the observed rates of gas transport in producing wells. Using containing limestone and different combinations of organic micro X-ray CT and NMR, we have measured gas transport in amendments indicate the presence of sulfate reducing bacteria whole cores under reservoir conditions. Rapid transport (SRB). Analysis of initial microbial community and SRB occurs in high permeability features sub-parallel to bedding, community via the 16S rRNA and dsrAB genes, respectively, followed by slower transport into the rock matrix surrounding suggest the presence of Desulfotomaculum, these features. The high permeability features are physical Desulfomicrobium and Desulfococcus. (2) Sulphur cycling is micro-cracks within the mineral matrix and at mineral-organic dynamic and strongly influenced by both biological and boundaries. It is impossible to prove that such features exist in abiotic processes. (3) Increasing bacterially-mediated sulfate undisturbed subsurface shales; however, we find a correlation reduction processes are associated with enrichment of 10-15‰ with their presence and well productivity. and precipitation of secondary sulfates is associated with 34 2- The work being presented was conducted by Max depletion of 1-2‰ in " S in residual SO4 . (4) Isotopic mass Deffenbaugh, John Dunsmuir, Aaron Eberle, Hubert King, balance calculations indicate that abiological sequestration Chris Kliewer, Pavel Kortunov, and Michael Sansone. was the dominant mechanism during the initial stage of the experiments and the low-temperature months. Our study demonstrates the applicability of the method to assess the rates, progress and environmental fate of pollutants associated with in AMD treatment processes.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2444 Goldschmidt2013 Conference Abstracts

Episodic growth of continental crust: Role of exopolymeric substances in A 3-D geodynamic model dolomite biomineralization by coastal UWE WALZER1* AND ROLAND HENDEL2 sabkha sulfate-reducing bacteria: an 1Institut für Geowissenschaften, F.-Schiller-Univ., Jena, ex situ study of microbial community- Germany (*correspondence: [email protected]) mineral interactions using solid- 2 Institut für Geowissenschaften, F.-Schiller-Univ., Jena, Germany ([email protected]) support imaging *WAN ABDUL-MATIIN1, BILAL MANSOOR2, AND The focus of this paper is the question (1) whether the 1 FARRUKH AHMAD observed zircon age distribution of continental crust (CC) is 1 produced by real crustal growth episodes or is only an artefact Bio-Energy and Environmental Laboratory (BEEL), Water of preservation. Question (2): In connection with the second and Environmental Engineering, Masdar Institute of alternative of (1), it has been proposed that there was little Science and Technology, PO Box 54225, Abu Dhabi, episodicity in the production of new CC and that modeling United Arab Emirates. *[email protected] 2 corroborates this opinion. In answer to (1), we conclude that a Advanced Materials and Manufacturing Laboratory, combination of the two proposals might be possible. In Materials Science and Engineering, Masdar Institute of matters of (2), we ascertain that a dynamic modeling of the Science and Technology, PO Box 54225, Abu Dhabi, convection-differentiation system of the mantle reveals the United Arab Emirates. [email protected] high probability of magmatic episodes. We solve the full set of balance equations in a 3-D spherical-shell mantle. The heat- While the microbial-mediation model has advanced producing elements are redistributed by chemical current understanding of modern dolomite genesis, the exact differentiation. A realistic solidus model of mantle peridotite mechanism remains speculative, especially in the context of is essential. The solidus depends not only on depth but also on microbial community architecture. Here we investigate the the variable water concentration. Furthermore, we introduced biofilm aspect of natural SRB growth within a dolomitizing realistic profiles of Grüneisen parameter, viscosity, adiabatic culture via analysis of media chemistry and surface temperature, thermal expansivity and specific heat. Our model formations. SRB from a coastal sabkha (western Abu Dhabi) automatically produces lithospheric plates and growing were studied vis-à-vis different quantities of exopolymeric continents. Regarding number, size, form, distribution and substance (EPS), under simulated sabkha pore water surface velocity of the continents, no rules have been conditions, and using inert solid support materials to capture prescribed. Regions of the input parameter space (Ra, $y, k, biofilm/biomineral growth. The experimental reactor with the f3) which are favorable with respect to geophysical quantities highest EPS content presented the most significant areal show simultaneously not only episodicity of CC growth but distribution of Mg-rich carbonate phases against reactors of also a reproduction of the observed zircon-age maxima lower/no EPS content (mean Mg/Ca molar ratio of 44.1% vs. referring to the instants of time. Admittedly, we also obtain 27.9%). More detailed microanalyses of major formations also 2+ Archean events for ages greater than 3000 Ma which are not revealed greater incorporation of Mg in saturated, partially or scarcely visible in the observed zircon ages. Sinusoidal degraded EPS aggregates (Mg/Ca molar ratio up to 91.2%) parts of the evolution curve of qob, Ur and Ekin are found compared to a growing biofilm matrix (Mg/Ca molar ratio up superposed with a monotonous decrease. Tmean, however, to 41.4%). Furthermore, a variety of mineral morphologies decreases smoothly and slowly, nearly without pronounced with varying levels of Mg incorporation were observed in variations. Therefore, we can dismiss catastrophic inoculated reactors supplemented with EPS, hinting at gradual mechanisms which simultaneously incorporate the whole dolomitization. Strategic nucleating sites for Ca-Mg mantle. carbonates appeared to be provided by aged EPS, while actively secreted and extensively growing biofilm EPS instead would initially inhibit mineralization through cation binding. Ca-Mg carbonate biomineralization might hence depend on the dynamic interplay of various physical, chemical and physiological conditions of local EPS that would constitute an optimal nucleating microenvironment.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2445

Thermal evolution of surface silanols Late Triassic adakitic rocks formed and nanopores in silica particles by partial melting of ancient mafic QUAN WAN*, SHANSHAN LI, ZONGHUA QIN lower crust in the North China AND YI XIAO Craton Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, CHAO WANG1 AND SHUGUANG SONG1* Guizhou, 550002, P.R. China 1 (* Correspondence: [email protected]) School of Earth and Space Sciences, Peking University, Beijing 100871, China Nanoporous structures have been commonly found in (*correspondence: [email protected]) rocks, soils, minerals, and organic matters. It is believed that nanopores are closely related to a range of vital geo-processes Adakites were originally defined as partial melts of young and geo-engineering applications, including rock weathering, subducting oceanic crust [1]. However, based on elemental enrichment and bioavailability, shale gas investigations of adakitic rocks in various settings, several exploration, carbon cycling and sequestration, etc [1]. Yet other genetic mechanisms have also been proposed, including knowledge gaps still exist toward understanding fundamental partial melting of slab-melt modified mantle wedge [2], structures and properties of nanopores. Difficulties and assimilation and fractional crystallization of basaltic magmas inaccuracies in determining nanopore structure and its [3], mixing between felsic and basaltic magmas [4], partial evolution easily lead to misinterpretation and contradiction of melting of thickened lower crust [5] and partial melting of experimental observation [2]. In this study, we used delaminated lower crust [6]. monodisperse, submicron-sized silica particle (synthesized Here we report the Late Triassic adakitic rocks in the through Stöber process) as our model system, which was eastern part of the North China Craton. They are granitic subject to dehydration (2hr at 200°C), dehydroxylation (2hr at gneisses with high SiO2 (68.87-70.15 %), Sr/Y (118-176) and 400~800 °C) and rehydroxylation (overnight boiling in water). (La/Yb)N (54-66) and low MgO (1.30-1.47 %), which are The thermally treated silica particles were subsequently similar to adakitic rocks formed by partial melting of characterized by thermogravimetry (TGA), differential thickened lower crust. In-situ zircon LA-ICP-MS U-Pb dating scanning calorimetry (DSC), TGA-IR, pycnometry, elemental reveals that they were emplaced in the Late Trassic (218-229 analysis and scanning electron microscopy (SEM), etc [3]. Ma). In-situ Hf isotope data for zircons show that they are Our experimental findings indicated that thermal evolution of characterized by the evolved $Hf(t) of -17.4 to -14.6 and TDM2 surface silanols for Stöber silica (~500nm diameter) accurately ages of 2.18-2.36 Ga, implying their source materials were fits with the Zhuravlev model for surface chemistry of extracted from the depleted mantle in the Paleoproterozoic. amorphous silicas [4]. For example, heating at 400°C Trace element modeling suggests that they might be produced quantitatively removed all vicinal silanol groups resulting a by 20-30 % partial melting of the Paleoproterozoic mafic weight loss (200~1000°C) of ~48.3% (i.e.,1.728/3.574 from lower crust materials equlibrated with eclogite residues TGA data), which was nearly identical to the calculated result (Grt/Cpx = 30/70). using theoretical silanol densities (i.e., 4.6, 2.35, and 0.25 Based on the above lines of evidence, plus the post- groups/nm2 at 200°C, 400°C and 1000°C, respectively; (2.35- collisional extensional enviroment in the Late Triaasic, we 0.25)/(4.6-0.25)=48.3%). Our results also indicated a fully propose that these adakitic rocks in the NCC were produced reversible recovery of silanol density through boiling in water through melting of the thickened ancient Paleoproterozoic and a specific surface area (SSA) of ~550 m2/g for silica mafic lower crust triggered by upwelling of basaltic magmas. treated #400°C. The large SSA apparently supports a Futhermore, they might be the result of the onset of nanoporous structure, which was observed to undergo lithospheric thinning of the NCC initiated in the Late Triassic. irreversible pore collapse when heating at above 600°C. This nanopore structure evolution is consistent with the results [1] Defant & Drummond (1990) Nature 347, 662-665. [2] from density measurements. Martin et al. (2005) Lithos 79, 1-24. [3] Castillo et al. (1999) Contrib. Mineral. Petrol. 134, 33-51. [4] Guo et al. (2007) J. [1] Wu et al. (2013) Geochim Cosmochim Acta 109, 38-50. Petrol. 48, 661-692. [5] Atherton & Petford (1993) Nature [2] Szekeres et al. (2002) Langmuir 18, 2678-2685. [3] Wan 362, 144-146. [6] Gao et al. (2004) Nature 432, 892-897. et al. (2010) J Therm Anal Calorim 99, 237-243. [4] Zhuravlev (2000) Colloid Surface A 173, 1-38.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2446 Goldschmidt2013 Conference Abstracts

Biomarker evidence for the Interaction of Bioavailability of Soil Neoproterozoic marine redox Heavy Metals in Black Soil Region of condition in South China Central Jilin Province CHUNJIANG WANG*, XIAOFENG XIONG, HAIFENG D.Y.WANG*, Y.F.LI, Y. Y.YANG AND X.L.YANG GAI, YUE LIU, BAOGANG LI, XUAN ZHOU AND BO XU Jilin University, College of Earth Sciences, Changchun, China State Key Laboratory of Petroleum Resources and ([email protected]*, [email protected], Prospecting, China University of Petroleum, Beijing [email protected], [email protected]) 102249, China, [email protected] (*presenting author) Heavy metal, which endangers ecological environment An important increase in atmospheric oxygen appears to directly and brings indirect harm by affecting the have taken place during the late Neoproterozoic period [1, 2]. bioavailability of soil nutrients, is an important substance This increase may have stimulated the evolution of resulting in soil pollution and degradation. Correspondently, macroscopic multicellular animals [1, 3] and may have led to nutrient elements in soil also affect the eco-environmental oxygenation of the deep ocean [4]. impacts of heavy metals. Thus, the interaction between heavy In order to understand more about the ocean oxygenation metals and nutrient elements, as a new aspect of pollution process during the Neoproterozoic period, a core spanning ecology of heavy metals, is important for maintaining 450m of stratigraphic section across Cryogenian Datangpo ecological balance. Fm. and Nantuo Fm., Edicarian Doushantuo Fm. and In present study, it is analyzed that the total and Dengying Fm., and early Cambrian Niutitang Fm. (ca. 663– bioavailability contents of heavy metals (Cr, Cd, Cu, Zn, Ni, 518 Ma), was drilled at Xiushan in South China. The As) and the contents of major nutrient elements (P, K, Ca, Mg, paleogeographic reconstruction suggests that Xiushan region Fe, B) for 61 surface soil samples in black soil region of was located at the outershelf margin to slope in the central central Jilin province, NE China. The bioavailability Yangtze platform of South China [5]. Here we report a secular characteristics of heavy metals are recognized according to the change in biomarker and Corg- and Ccarb-isotopic compositions effective coefficients of soil elements (available contents of based on this drillcore section, which aims to reveal the elements in soil accounting for total amounts). And the difference in organic matter sedimentation and marine redox effective coefficient correlations for different heavy metal as condition between the interglacial Datangpo Fm. and well as the heavy metals and nutrient elements are calculated postglacial Doushantuo Fm., and the difference between the by SPSS (Ver. 13.0). outershelf-slope facies Doushantuo Fm. at Xiushan region and The obtained results indicate that all the following the innershelf basin facies at the Jiulongwan section. effective coefficient correlations are obvious positive, (1) Cd Organic geochemical evidence shows that the Datangpo and Zn with the other heavy metals, (2) Cr with As, Cd, Zn Member I and II could deposit in dysoxic and oxic condition, and Ni, (3) Ni with Cr, Cd and Zn, (4) As with the Cr, Cd, Cu respectively. It means that the Datangpo Member I black shale and Zn. These findings indicate that the bioavailability was likely not deposited in an anoxic or euxinic condition as conversion of heavy metals have promoting effect to each suggested before [6]. Obvious difference in Doushantuo biomarker assembly occurs between Xiushan region other in study area. (outershelf–slope) and the Jiulongwan section (innershelf Remarkably, the effective coefficients of six heavy metals basin), which may have been caused by differential redox show obvious positive correlations with P, which is consistent conditions or depositing processes of organic matters. Our with the major standpoint about the interaction between P and data support the idea that the reconstruction of the redox heavy metals in soil, implying that the effective content of P condition in Cryogenian and Edicaran oceans should be based plays a role in promoting the activation of heavy metals. on approaches from various facies ranging from shallow Additionally, these results indicate that the following effective marine shelf to deep marine basin [5, 7]. coefficient correlations also exhibit obvious positive, (1) micronutrient element B and Fe with As, Cu and Zn, (2) [1] Fike et al. (2006) Nature 444, 744–747. [2] Canfield et al. between Fe and Cr, (3) Mg with Cr, Ni and Zn. However, the (2007) Science 315, 92–95. [3] McFadden et al. (2008) PNAS effective coefficient of Ca has obvious positive correlations 105, 3197–3202. [4] Rothman et al. (2003) PNAS 100, 8124– with heavy metals except Cu. And the correlations between 8129. [5] Jiang et al. (2011) Gondwana Res. 19, 831–849. [6] the effective coefficients of K and As exhibits obviously Li et al. (2012) EPSL 331–332, 246–256. [7] Zhu et al. negative. (2007) PPP 254, 7–61. In short, study on interaction of bioavailability of elements provides insights to understand the black soil degradation ! mechanism, prevent heavy metal pollution, balance the nutrients, and strengthen management of the black soil resource.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2447

Petrology, geochemistry and Zircon U-Pb-Hf-O isotopes and REE metamorphic evolution of constrains on the origin of Mesozoic metamorphic rocks in Diancang ore-bearing high Mg# adakitic rocks Shan-Ailao Shan metamorphic from Ningzhen area of east China: complex belt, Southeastern Tibetan Petrogenesis and tectonic Plateau implications

1 2 2 FANG WANG, FULAI LIU, PINGHUA LIU, JIANRONG SHI FANGYUE WANG *, SHUGUANG LIA, *, SHENG-AO LIU AND JIA CAI AND SHEMIN AKHTARA1 Institute of Geology, Chinese Academy of Geological 1CAS Key Laboratory of Crust-Mantle Materials and Sciences , Beijing 100037, China Environments, School of Earth and Space Sciences, ([email protected]) University of Science and Technology of China, Hefei 230026, China Combined study of petrology, geochemistry and 2 State Key Laboratory of Geological Processes and Mineral metamorphism of meta-sedimentary rocks and meta-basic Resources, China University of Geosciences, Beijing rocks, provide clear evidence of metamorphic evolution of 100083, China Diancang Shan-Ailao Shan metamorphic complex belt. Detailed geochemical analysis in the meta-sedimentary rocks Cu-Mo-Fe mineralized high Mg# adakitic porphyries and amphibolites suggest the protoliths of claystone, siltstone, intruded in the eastern Lower Yangtze River Belt (LYRB), but graywacke and island-arc basaltic rock, respectively. the timing and petrogenesis of these adakites are not well Microprobe and mineral inclusions analysis reveals that garnet constrained. In this study, five samples were collected from porphyroblasts in meta-sedimentary rock bear a chemical the ore-bearing adakites (Anjishan Cu deposit, Tongshan Cu- composition zonation from core to rim. On the basis of Mo deposit and Xiangshan Fe deposit) of Ningzhen region, in paragenesis, mineral transformation and chemical composition order to precisely constrain their formation ages, petrogenesis zonation of garnets, four metamorphic stages have been and tectonic settings. Zircon U-Pb ages dated by LA-ICP-MS recognized, i.e. early prograde metamorphic stage (M1), peak show that ore-bearing adakite in Ningzhen region are about amphibolite-granulite facies metamorphic stage (M2), near 110-118 Ma, obviously younger than ore-bearing adakites isothermal decompression retrogression metamorphic stage (140±5Ma), bimodal volcanic rocks with A-type granites 4+ 3+ (M3), and late amphibolite facies retrograde stage (M4). The (126-131Ma) along the LYRB. Magmatic zircon Ce /Ce of paragenesis of Grt + Pl + Ms + St ± Ky ± Bt ± Kfs + Qz adakites ranges from 4-1615, compatible to those from the (meta-sedimentary rocks), which formed at 560 ~ 590°C and older adakites in LYRB. Zircon Hf and O isotopes from 5.5 ~ 6.3 kb, is regarded as the M1 stage mineral assemblage. Ningzhen adakites show a wide range from -10.58 - -23.35 The typical mineral assemblage of M2 stage, which constrains and 5.74-7.03‰, respectively, fall between those of the LYRB P-T condition of 720 ~ 760°C and 8.0 ~ 9.3 kb, contains Grt + and South Tan-Lu fault zone (STLF). Zircon Ti-thermometry Bt + Ky/Sil + Pl + Qz or Grt + Bt ± Sil + Pl ± Kfs + Qz (meta- of Ningzhen adakites range from 550-700 oC, averaged at 650 sedimentary rocks) and Grt + Cpx + Pl (meta-basic rocks). oC, similar to those from the LYRB too. Zircon O-Hf- The paragenesis of Grt + Bt + Sil + Pl + Qz (meta-sedimentary Ce4+/Ce3+ and Ti-thermometry from the Ningzhen ore-bearing rocks) and Hbl + Pl ± Cpx ± Bt ± Qz (meta-basic rocks) porphyries show their magma source may from an oxidized defines M3 stage mineral assemblage, occurring at P-T water-rich sources with continental crust involvement. Genesis condition of 650 ~760°C and 5.0 ~ 7.3 kb. Newly formed of adakites in Ningzhen region is best explained by intersectional biotite and muscovite, together with the rim of assimilation between metasomatised mantle and lower garnet, define the M4 stage mineral assemblage of Bt + Ms + continental crust and followed by fractional crystallization. Pl ± Kfs ± Grt + Qz (meta-sedimentary rocks), inferred at 553 Combined with published ages data of ore-bearing adakites ~ 613°C. The metamorphic complex, record a clockwise from the LYRB, Mesozoic magmatic activities from LYRB metamorphic P-T trajectory characterized by near isothermal show a younging trend from inland to outland. A slab flat decompression. The integrated clockwise P-T path established subducting and rolling back evolution model of the LYRB is for metamorphic complex in Diancang Shan-Ailao Shan proposed in this study. metamorphic complex belt is a potential record of geodynamic process related to subduction-collision-exhumation between Indian and Eurasian plate.

This study was financially supported by the Nation Natural Science Foundation of China (Grant no. 40921001 and 40725007) and by a Chinese Geological Survey Bureau project (Grant no. 1212011121276)

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2448 Goldschmidt2013 Conference Abstracts

Hydrocarbon Mobility Prediction for Neoproterozoic terranes in the NE lacustrine shale oil plays China and its tectonic implications WANG, FEIYU1, WEIPING FENG1 AND ZHIYONG HE2 FENG WANG, WENLIANG XU*, FUHONG GAO, JIE TANG, 1 AND WENLI HAO China University of Petroleum, Beijing,102249) 2 Zetaware Inc., Sugar Land, TX. 77479 USA College of Earth Sciences, Jilin University, Changchun 130061, ([email protected], * [email protected]) Lacustrine shale oil plays or tight oil systems have become the important exploration and development target in China, a NE China is located in the eastern section of the Central great amount residual hydrocarbon exist in the mature organic Asian Orogenic Belt (CAOB), in a region that consists of a matter rich lacustrine shale plays, For a shale play to work, it collage of several microcontinental massifs (including, from has to have enough original oil in-place volumes and northwest to southest, the Erguna, Xing’an, Songnen- producible, The occurrence and mobility of residual Zhangguangcai Range, Jiamusi, and Khanka massifs). It has hydrocarbon are key to assessment of shale oil plays. been a controversial issue whether did the Precambrian Residual hydrocarbon can be splited into two terranes occur within these microcontinents of NE China, parts, free oil and adsorbed oil, the former occur in the organic although the geochronolical data of the detrital zircons from matter rich source rocks intervals and interbedded various the Paleozoic strata in NE China display a lot of the scale tight reservoir layers within the shale plays, the latter information the Precambrian ages. Additionally, the tectonic are mainly located in organic matters in the shale plays. The attribution of these microcontinents is also an unsolved issue. amount of adsorbed oil for lacustrine shale range from 80 The Neoproterozoic magmatisms, corresponding to the mg/gTOC to 100 mg/gTOC, which will be decreased with breakup of the Rodinia supercontinent, have been widely maturation increase.The most of adsorbed oil in a shale play identified in the Erguna Massif [1]. By comparison, no are immobile and hard to produce. The free oil appear when igneous rocks of this age have been identified in the Xing’an, residual oil is higher than the adsorbed oil threshold. the more Songnen–Zhangguangcai Range, and Khanka massifs. free oil amount correspond to the higher mobility for shale oil. However, the LA-ICP-MS detrital zricon U-Pb dating for Viscosity is very important to hydrocarbon mobility, but less Dongfengshan and Tadong groups indicate that a suite of predictable quantitatively, As maturity or transformation ratio Neoproterozoic terranes is present along the eastern margin of increases, GOR increases four orders of magnitude and the Songnen–Zhangguangcai Range Massif (~821–752 Ma, viscosity decreases three orders of magnitude in the oil ~752–560 Ma, and ~750–516 Ma)[2]. And Neoproterozoic window,.The kinetic model of GOR,API and viscosity have magmatic zircons (0.75–0.92 Ga) are the most common been established for the organic rich lacustrine source rock, If zircons identified in the Dongfengshan and Tadong groups, maturity or transformation ratio of source rocks can be suggesting that a Neoproterozoic magmatic event occurred measured ith much greater precision, the viscosity and within the Songnen-Zhangguangcai Range Massif. The detrital hydrocarbon mobility will be predicted in reasonable zircons with similar ages (0.76–0.97 Ga, our unpublished data) resolution. Vitrinite reflectance data are often problematic for have been also identified in the Huangsong Group along the lacustrine shale play when used for the maturity or thermal western margin of the Khanka Massif. Additionally, calibration,a better approach is calibrated with the residual HI increasing evidence suggests that Neoproterozoic magmatic of high TOC source rocks. Higher maturity means lower zircons are present in Paleozoic sedimentary rocks in the viscosity, maturity map will provide the hydrocarbon mobility Xing’an Massif [3]. trending in the area. The above findings suggest that the Precambrian terranes Case studies from the Hataoyan Formation of Biyang did occur within the Erguna, Xing’an, Songnen- basin and Upper Triassic Chang 7 Shale in Ordos basin have Zhangguangcai Range, and Khanka massifs, and that these been shown the approaches of hydrocarbon mobility microcontinents have an affinity to the Siberia craton. This prediction in the lake basins. these case studies indicate that research was financially supported by the National Science the best oil production seems to be from late oil window with Foundation of China (Grant 41272075 and 41072038). vitrinite reflectance equivalent of 0.9 to 1.2 (%Ro). [1] Tang et al. (2013) Precambrian Research 224, 597–611. [2] Wang et al. (2013) Gondwana Research, in press. [3] Han et al. (2011) Tectonophysics 511, 109–124.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2449

Understanding the sub-surface Seasonal patterns of CO2 emission metabolic activity and pathways of from a subtropical reservoir microbial mediated C/N cycling in FUSHUN WANG1 BAOLI WANG2 AND CHENCHEN YAO1 North Pond, western flank of 1 School of Environmental and Chemical Engineering, Mid-Atlantic Ridge Shanghai University, Shanghai 200433, China. [email protected] 1 2 1,2 FENGPING WANG *, XINXU ZHANG , YUEHENG ZHOU , 2 State Key Laboratory of Environmental Geochemistry, AND THE IODP EXP336 SCIENCE PARTY, Institute of Geochemistry!Chinese Academy of Sciences, 1State Key Laboratory of Microbial Metabolism and State Key Guiyang 550002, China. [email protected] Laboratory of Ocean Engineering, Shanghai JiaoTong University, Shanghai, 200240, People’s Republic of China The XinAnJiang River, is the mainstream of Qiantang *Correspondence: [email protected] River, the largest river in Zhejiang Provence, China. The XinAnJiang Reservoir, located in Chun’an County, Zhejiang Province, was accomplished in 1959, also known as the This project tries to reveal the microbial mediated C/N Qiandao Lake. Five cruises were carried out along the cycling in the sediments and rocks of North Pond, western XinAnJiang Reservoir and its river reach in April, June, flank of Mid-Atlantic Ridge, which represents an ideal model August, November 2010 and January 2011, in order to system for studying the biologically mediated oxidative understand the CO2 emission from this subtropical reservoir. basement alteration. A series of incubations with 13C and 15N pCO2 of surface water was determined using a continuous labeled substrates including sodium carbonate, acetate, measurement system (equilibrator-NDIR system), besides that methane, ammonium chloride and sodium nitrate, have been sampling and analysis of the outflow water and the water set up onboard. Significant cell growths were observed only column in front of the dam were also conducted in each cruise. when nitrogen substances were supplemented, either alone, or The results showed that, pCO2 in the surface water strongly in combination with carbonate or acetate. This data suggests varied during the whole year, ranging from 5%atm to that nitrogen is the limiting nutrient source for cell growth in 1,300%atm at the inflow reach, from 2%atm to 1,000%atm at the North Pond crust biosphere. The microorganisms and their the central reservoir area, and from 1400%atm to 3,800%atm at utilized pathways in the assimilation and transformation of C, the outflow water, respectively. In the inflow river reach and N are under investigation. In addition, enrichment and central reservoir, the highest values of surface water pCO2 isolation of microbial groups involved in iron transformation appeared in winter, and the lowest in summer. While the will also be performed. These integrated studies would give outflow water, has the highest surface pCO2 in summer, and clear clues to understand the underwater microbial activities, the lowest in spring. Along the water column in central key metabolic pathways and their roles in ocean crust reservoir, pCO2 increased downwardly. In summer, the weathering. ! difference between pCO2 in surface water and bottom water reached to 5,900%atm, and in spring this difference was only

50%atm. The annual average pCO2 in inflow waters, reservoir surface and outflow waters were all higher than that of

air(380%atm), and the annual average diffusion flux of CO2 at water-air interface in these area were 11.37, -0.02 and 345.93 mmol·m-2·d-1, respectively, which indicated that the

Xin'AnJiang reservoir should be a CO2 source to the atmosphere. However our result also showed that central

reservoir indeed has a role in mitigating the CO2 emission in this case.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2450 Goldschmidt2013 Conference Abstracts

Organic carbon proxies in black Simultaneous measurements of C and shales: strontium N Isotopic composition and N H.J. WANG1, X.M. WANG1 AND S.C. ZHANG1* abundance in diamonds by 1Research Institute of Petroleum Exploration & Development, NanoSIMS CNPC, Beijing 100083, China JIANHUA WANG *, STEVEN B. SHIREY ([email protected], AND ERIK H. HAURI [email protected], *correspondence: [email protected]) Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Rd. NW, Washington Isotopic and elemental proxies are used to discern the DC 20015, USA (*correspondence: [email protected]) original compositions of ancient sediments, which are subject to later diagenetic/thermal alteration, etc[1]. Recent work about Diamond, one of the three native carbon minerals on the Mesoproterozoic (1.36 Ga) black shales in the North China Earth, has been intensively studied for more than 40 years to Craton showed a high correlation between total organic carbon provide extraordinary information on the cycling of carbon in (TOC) content and the enrichment factors of Sr normalized to the Earth’s interior. Diamonds are found at the Earth’s surface upper crust (Sr EF = (Sr/Al)sample/(Sr/Al)upper crust). No matter in ultra-high pressure metamorphic terranes, meteorite impact which paleoredox conditions is, the relatively low Sr EF (< sites, and volcanic eruptions of kimberlite magma or their 1.0) and good positive correlation with TOC (Figure 1), weathering products. It is the kimberlitic diamonds that means the uptake of Sr is mainly controlled by the availability provide the largest and deepest specimens - from 150 km to of organic substrates, not the solubility at the redox boundary. 800 km depth in the mantle. Multi-stage growth patterns are Besides the isotopic compositions of Sr can reflect the commonly seen in the cathodoluminescence (CL) imaging of evolution of paleocean[2], thus jointly estimates of original diamonds, including those that are large, transparent TOC with the content and isotopic composition of Sr in monocrystals. The SIMS method has been developed to study samples spanning the geologic record, should be useful in zonation of carbon and nitrogen isotopic composition and estimating the of primary productivity of ancient oceans and nitrogen abundance in diamonds [1] and is the method of the distribution of potential source rocks of petroleum. choice for study in the context of the zoning patterns. Separate analytical sessions are require to measure carbon and nitrogen isotopes and nitrogen abundance in the previous method on the Cameca 6f [1] because a single detector must be used at different mass resolution for C and N. We have developed a method to measure both carbon and nitrogen isotopes and nitrogen abundance simultaneously on the same spot using multicollection on the Carnegie NanoSIMS 50L. The NanoSIMS method has a better special resolution (15µm) with better precisions ("13C: 2s of ±0.5‰ and "15N: 2$ of ±2.2‰) and much better transmission of nitrogen (12C14N: 1600cts/ppm/nA). We will discuss the details of the NanoSIMS method comparing with the previous method. Palot et al. reported lowest "15N values (up to -39.4‰) of terrestrial sample in Kankan (Guinea) diamonds [2]. They Figure 1: Enrichment factors of Sr (relative to upper interpreted this low N isotopic composition as the primordial crust) versus TOC in Mesoproterozoic sediments. heterogeneity preserved in an imperfectly mixed convective mantle [2]. We measured "15N value of -29‰ in a peroditic [1] Wilde et al. (2004) Chem Geol. 206, 167-176. [2] diamond from Liaoning, China. In situ and simultaneous Veizer et al. (1999) Chem Geol, 161, 59-88. measurements of C and N isotopic compositon and N abundance in zoned Liaoning diamonds reveal their complicated growth history and N isotope geochemistry in the deep Earth. [1] Hauri et al. (2002) Chem. Geol., 185, 149-163. [2] Palot et al. (2012) EPSL, 357-358, 179-193.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2451

Multi-scale simulation of structural Gallionella-like microorganisms heterogeneity of swift-heavy ion involved in iron oxide formation in tracks in complex oxides groundwater wells across a broad pH JIANWEI WANG*, MAIK LANG, RODNEY C. EWING AND range UDO BECKER 1 2 JUANJUAN WANG , MAREN SICKINGER Department of Earth and Environmetnal Sceinces, University AND KIRSTEN KÜSEL3 of Michigan, Ann Arbor, Michigan 48109 USA 1Friedrich-Schiller-University of Jena, Dornburgerstr.10 (*correspondence: [email protected]) 07743 Jena,( [email protected] Understanding and prediction of the phase behavior of [email protected] materials under extreme environments provide a great [email protected]) challenge in the materials’ design and engineering in various applications. Swift heavy ion have been used to probe the Clogging caused by iron ochre incrustations has been a effect of the high-energy radiation on a wide variety of challenge for the functioning of groundwater wells, especially materials and to explore the complex far-from-equilibrium technical wells in mining areas. The formation and dissolution behavior of the materials under extreme conditions. In this of iron oxides can be mediated by iron-oxidizing and - study (J. Phys.: Condens. Matter,25,135001), track formation reducing microorganisms. In this project we studied the caused by a swift-heavy ion irradiation, 2.2 GeV Au, of potential role of these microbes in the clogging process at Ti O pyrochlore and orthorhombic Gd TiO isometric Gd2 2 7 2 5 three locations in an open-cast mine, comparing a total of 16 phase was modeled using thermal-spike model combined with wells. The groundwater had pH ranging from acidic (4.5) to a subsequent molecular-dynamics simulation. The thermal- neutral (7.5) and relatively high contents of Fe(II) (0.5~7 mM) spike model was used to calculate the energy dissipation over -1 and DOC (1.4~12.6 mgL ) at an average oxygen time and space. Using the time, space, and energy profile concentration of 3.8 mg L-1. The mineral composition of generated from the thermal-spike calculation, the molecular- ochres differed with ferrihydrite being common in dynamics simulation was performed to model the atomic-scale circumneutral wells and schwertmannite dominating in the evolution of the track. The advantage of combining these two slightly acidic wells. 454 pyrosequencing revealed a high methods, that is using the output from the continuum model as diversity of bacteria in the ochres with a large fraction of an input for the atomistic model, is that it provides a means of Gallionella-related sequences. Quantitative PCR suggested simulating the coupling of the electronic and lattice that Gallionella-related organisms on average accounted for subsystems and at the same time providing atomic-scale 44 % of the total bacteria. Surprisingly, their abundance was details of the track structure and morphology. not correlated to any geochemical parameter. Gallionella- The simulated internal structure of the track consists of an related organisms were also present in the ground water amorphous core and a shell of disordered, but still crystalline, ranging from 8.4&106 to!2.0&108 16S rRNA gene copies per L Ti O , the shell region has a disordered domains. For Gd2 2 7 water. Iron reducing bacteria such as Geobacter, Geothrix, pyrochlore with a defect fluorite structure and is relatively Rhodoferax, were only detected at low abundance, in thick and heterogeneous with different degrees of disordering. agreement with a low iron reduction potential. However, the For Gd TiO , the disordered region is relatively small as 2 5 iron reduction potential could be stimulated by the addition of compared with Gd Ti O . In the simulation, “facets”, that is 2 2 7 lactate. In conclusion, Gallionella-related iron oxidizers surfaces with a definite crystallographic orientation, are dominated ochres and groundwater irrespective of pH, apparent around the amorphous core and were more evident in suggesting a major role of these organisms in the formation of Gd TiO along the [010] than [001], suggesting an 2 5 ochres across a broad range of geochemical conditions. orientationally dependent radiation response of this structure. Deeper insight into the microbiology of the ochre formation These results show that track formation is controlled by the process may help to develop strategies for relieving clogging coupling of several complex processes, involving different problems in technical wells. degrees of amorphization, disordering, and dynamic annealing. Each of the processes depends on the mass and energy of the energetic ion, the properties of the material, and its crystallographic orientation with respect to the incident ion beam.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2452 Goldschmidt2013 Conference Abstracts

Geochemical fingerprints in Siberian Compositional variation in apatites mantle xenoliths reveal progressive from carbonatites and associated erosion of an Archean lithospheric alkaline silicate rocks: A case study of root the Kaiserstuhl complex, Germany KUO-LUNG WANG1*, Y.-H. CHIEN1, M. I. KUZMIN2, L. WANG1,3", T. WENZEL1, A. VON DER HANDT2, SUZANNE.Y. O’REILLY3, W.L. GRIFFIN3, J. KELLER2, M. A. W. MARKS1 AND G. MARKL1 2 3 A. VORONTSOV AND N.J. PEARSON 1 Universität Tübingen, Mathematisch-Naturwissenschaftliche 1Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan Fakultät, FB Geowissenschaften, 72074 Tübingen, (*correpsondence: [email protected]) Germany 2Institute of Geochemistry, SB RAS, Irkutsk, Russia ( *correspondence: [email protected]) 3CCFS/GEMOC, Macquarie University, Sydney, Australia 2Albert-Ludwigs-Universität Freiburg, Institut für Geowissenschaften-Mineralogie-Geochemie, 79104 Mantle xenoliths from a picrobasalt quarry in Miocene Freiburg, Germany (14 Ma) and Holocene (~0.65 Ma) basalts of the Bulykhta 3Faculty of Earth Sciences, China University of Geosciences, Riverside and Kandidushka volcanoes in the Vitim volcanic 430074 Wuhan, China plateau, SE Siberia, are dominantly spinel-, garnet-, or garnet– spinel-bearing lherzolites with minor pyroxenites. Equilibrium In the present study, we investigate textural and chemical temperatures and pressures of garnet-bearing lherzolites in the signatures of apatites from a series of carbonatites, related Miocene basalts range from 1110 to 1250 °C and 22 to 28 alkaline silicate rocks, an unusual carbonate-bearing melilitic kbar, whereas those in Holocene basalts have similar dyke rock (bergalite) and a diatreme breccia of the Miocene temperatures (1110–1180 °C) but lower pressures (20 - 21 Kaiserstuhl Volcanic Complex, South Germany. kbar). The latter thus yield a hotter geotherm than the former. Significant chemical differences between apatite from The Fo contents of olivine in these lherzolites range from 89.1 carbonatites and associated alkaline silicate rocks exist for Sr, to 90.6, with most from 89.8 to 90.2. Trace-element patterns Fe, Mn, Th, U, Nb, Si, S, As, Cl and Br. These differences can of clinopyroxenes (cpx) in the lherzolites can be divided into be attributed to different partition coefficients, melt three types: depleted, enriched and intermediate. The depleted compositions, substitution mechanisms and redox conditions. patterns are typical of unmetasomatised, refractory A systematic and sharp core-mantle-rim zonation is lithospheric mantle. The enriched and intermediate ones present in apatites from the bergalite sample. The core and provide fingerprints of different metasomatic episodes. Some mantle zones are compositionally similar to apatites from lherzolites contain amphibole and/or apatite as evidence of silicate rocks, whereas the rim compositions correspond to that modal metasomatism. Whole-rock and cpx Sr–Nd isotopic of carbonatitic apatites. These observations imply that ratios of lherzolites in Miocene basalts are more radiogenic bergalititic apatites initially nucleated in a siliate melt and 87 86 143 144 ( Sr/ Sr=0.70225-0.70561 and Nd/ Nd=0.51288- continued crystallizing from a melt with carbonatitic affinity 87 86 0.51303) than those in Holocene basalts ( Sr/ Sr=0.70244- during later stages. This late-stage carbonatitic melt was 143 144 0.70374 and Nd/ Nd=0.51300-0.51329). It indicates the interpreted as the protracted fractionation product of the material sampled from the SCLM beneath the Vitim region in carbonate-bearing nephelinitic melt #$%& Holocene time is more depleted than that sampled in the Apatites from a diatreme breccia (containing carbonatitic Miocene. Os isotope compositions of sulfides display simiar and silicate rock components) comprise three textural and temporal variation; the lherzolites in the younger basalts have compositional populations: (1) similar to apatites from silicate 187 188 more radiogenic ratios ( Os/ Os=0.1066-0.1318) than those rocks, (2) similar to apatites from carbonatites, and (3) 187 188 in the older basalts ( Os/ Os=0.1168-0.1350). Both TMA resembling apatite population (1) partially replaced by 187 188 ages from the least-disturbed sulfides ( Re/ Os<0.07) and population (2). We infer that apatite population (1) derived TRD ages from higher-Re/Os sulfides yield model ages ranging from silicate rock fragments and apatites (2) crystallized from from 0.5 to 3.2 Ga, with peaks around 1.4, 1.1, 0.9 and 0.5 Ga. the later intruding carbonatitic melt causing the formation of The Miocene basalts sampled a deeper, more refertilised part the breccia. During ascend of the carbonatitic melt, of the Archean root, compared to the shallower part sampled metasomatic overprint caused the observed replacement by the Holocene basalts. textures in apatite population (3).

[1] Keller (1997) Geol.Ass./Mineral.Ass. Annual Meeting. Abstract, A77.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2453

Research on the phase compostion , Petrogenesis of Late Permian picritic expansion property and heavy metals porphyries associated with Pingchuan absorption capacity of vermiculite iron ores, Emeishan Large Igneous from Yuli Xinjiang Province Province, southwest China L.J. WANG, L.B. LIAO* AND X.X. HUO MENGWANG1 AND ZHAO-CHONG ZHANG 1 School of Material Sciences and Technology, China 1 State Key Laboratory of Geological Processes and Mineral University of Geosciences, Beijing 100083, China Resources, China University of Geosciences, Beijing, (*correspondence: [email protected]) 100083, China ([email protected])

Vermiculite is a kind of natural, non-toxic clay, which was The Pingchuan iron oxide deposit is spatially and temporally formed from mica weathering or alteration. The Qeganbulak associated with the Late Permian picritic porphyries in the vermiculite ore in Yuli, Xinjiang province is one of the largest Emeishan Large Igneous Province, southwest China. The vermiculite deposits discovered in China, which is about 90% estimated ore reserve for the Pingchuan deposit is 40Mt at ~60 of the vermiculite reserves in China. Because of its layer ions wt.% Fe. The iron ore bodies are intimately associated with exchangeability, vermiculites have strong cation exchange the intrusive masses of picritic porphyry, occurring mainly capacity, which can be used to remove heavy metals in along the contact zone between the picritic porphyries and the wastewater. sedimentary country rocks, i.e. limestone. The most important Under the investigation of X-ray diffraction(XRD), ore types are massive and brecciated ores which together make thermogravimetric–differential thermal analysis(TG-DTA), up 90 vol. % of the deposit. The massive type generally occurs infrared spectroscopy(IR), and chemical analysis etc., as dykes and large veins consisting predominantly of vermiculite from Yuli Xinjiang was approved to a mixture of magnetite with minor calcite and apatite. The picritic vermiculite, mica, calcite and two kinds of vermiculite-mica porphyries are characterized by a marked range of SiO2 mixed-layer minerals Hy-a (vermiculite/mica mole ratio of (37.12-47.39 wt. %) and MgO (19.22-29.08 wt. %), but show 6:4), Hy-b (vermiculite/mica ratio of 4:6). Phlogopite was a minor variation in Na2O+K2O (0.12-1.58 wt. %) and TiO2 identified as the major type of mica in mica layer in mixed- (0.64-1.44 wt. %). The total concentration of rare earth layer minerals. A small amount of biotite cannot be expelled. elements (REE) is relatively low (21-83 ppm), and show Vermiculite are Mg type vermiculite and Na type vermiculite. moderate enrichment in light rare earth element (LREE; Results show that expansion capacity of vermiculite [La/Yb]N=3.01-3.63). The primitive-mantle-normalized majorly comes from mixing layer minerals(Hy-a, Hy-b), in patterns of the rocks are comparable to those of ocean island which Hy-a affect its expansion ability most. The expansion basalt, plausibly indicating a plume source. Petrographic ratio of vermiculite increases with the increase of temperature observation suggests the Pingchuan picritic porphyries are when the temperature is less than 700 ', after then it’s virtually cumulus product, and possibly experienced fractional becoming stable. The expansion ratio of vermiculite reduces crystallization of Cr-spinel + olivine + clinopyroxene during with the increase of particle size. The expansion ratio of the magma chamber process. Moreover, the estimated vermiculite is the highest when its particle size ranges from 1 primitive magma composition is picritic which is possibly to 2 mm. When particles are bigger than 2mm, its expansion produced by partial melting of the garnet-facies ratio decreases with the increase of particle size. asthenospheric mantle peridotite. In combination with the Before reaching the absorption/desorption balance of available information including field observation and vermiculite towards heavy metal ions like Cd,Cu,Cr etc., the geochemical studies, e.g. fluid inclusions and stable isotope absorption capacity is positive to absorption time, however, data, we infer that the deposit is hydrothermal in origin and after reaching this balance, absorption time won’t increase the ore-forming fluids are predominantly primary magma- absorption capacity obviously . In addition, the absorption derived fluids which had been released during the post- capacity of vermiculite towards heavy metals increases with magmatic period and mixed with fluids from country rocks. the increase of concentration of heavy metals. The vermiculite’s absorption capacity towards heavy metals can also be phenomenally affected by pH, normally, higher pH can cause higher absorption capacity.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2454 Goldschmidt2013 Conference Abstracts

Carbonate reservoir features and its Geochemical characteristics of main control factors in South Slope of sediment of Pearl river estuary and Northern Tarim, China its palaeoenvironmental evolution RUIJU WANG, ZHENG HONGJU, JIANG HUA, CHUNMING WANG SHANSHAN1  CAO ZHIMIN2 ZHANG, SUYUN HU, ZECHENG WANG AND LAN DONGZHAO2.3 (PetroChina Research Institute of Petroleum Exploration & 1 Zhejiang Institute of Hydraulics & Estuary, Hangzhou, Development, Beijing 100083, China) 310020, China(correspondence:[email protected]) 2 College of Marine Geosciences, Ocean University of China, Good exploration prospects have been shown in carbonate Qingdao, 266003,China of lower Ordovician, which's depth is larger than 6500m, in 3 Third Institute of Oceanography, SOA, Xiamen 361005, south slope of Northern Tarim, but carbonate reservoir China features and its attributions have not been completely known. In this research, cores, glass slides, logs, 3-d high resolution Data and method seismic,and so on, are used. And researching methods such as The concentration of metal elements(Co, Cu, Zn, Ni, Cr, tectonic evolution analyzing, reservoir feature depicture, and Zr, Sr, Ba), total content of organic matter and average grain so on, are applied. Types,periods,distribution and overlapping size were determined from 16 sediment samples in different method of karst were studying in this area. It was recognized depth of 3.5m core in Pearl River estuary of China. Three that different karsts played the various parts in different areas. important factors were identified from 160 data, using North area of Tumuxiuke pinch-out developed potential karst, principal component analysis method. while most areas on the south side developed alonging-karst. Discussion of Results It was particular that Yingmai area developed vertical karst. The variance contribution(Tab1) shown the effect for Complexity of karst reservoir was decided by attribution of chemical composition of sediment, and after further analysis, high -energy facies and history of tectonic evolution. Research We found that, the three factors represented catchment erosion on superimposing pattern of karst and different features was (F1), biogenic deposit (F)and marine dominated going to help the exploration in the research area. condition(F3)(Tab1) respectively. The factor score curves(Fig1) represented the changes of humidity and temperature and the hydrodynamics in different depth(times). Variance Factors Variables and factor loading contribution % Co0.873,Cu0.906,Ni0.925,Zn0.807, F1 42.06 Cr0.628, Average grain size 0.710 F2 Sr 0.885, Ba 0.949 21.95 F3 Zr 0.748, TOC -0.937 21.58 TOC:total organic carbon Table1: Result of factor analysis

Figure 1. Lines of factor scores in different depth The study provided an effective approach for palaeoenviroment reconstruction of Pearl river delta. It revealed that the basic palaeoclimate succession in the region of Pear river delta is cool-humid, cool-dry, warm-dry, warm- dry , warm-humid and warm-dry successively.

(This work was founded by National Science Foundation of China (41006052))

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2455

Factors influencing methane-derived A Prediction Model of Oil Cracked authigenic carbonate formation at Gas Resources and Its Application in cold seep from southwestern Dongsha NE Sichuan Basin, SW China area in the northern South China Sea T.S.WANG*, S.Y. HU AND X. LI SHUHONG WANG1,2, WEN YAN1,2*, VITOR H. PetroChina Research Institute of Petroleum Exploration & MAGALHÃES3, ZHONG CHEN1,2, LUIS M. PINHEIRO3, A Development,Beijing,China(*correspondence:wts2007@p AND NIKOLAUS GUSSONE4 etrochina.com.cn) 1 The prediction of oil cracked gas resources is necessary CAS Key Laboratory of Marginal Sea Geology, South China and urgent in the gas exploration of these basins at high to Sea Institute of Oceanology, Chinese Academy of over stage in China. A marine crude oil sample was pyrolyzed Sciences, Guangzhou 510301, China (*[email protected]) 2 using sealed gold tubes systemin our study. The pyrolysates Guangzhou Center for Gas Hydrate Research, Chinese including gas, liquid, and solid were quantitatively analyzed. Academy of Sciences, Guangzhou 510301, China 3 Based on the pyrolysis data and kinetic calculation, the yield Centre for Environmental and Marine Studies (CESAM) and correlativity among gas, liquid, and solid products was Geosciences Department, University of Aveiro, Aveiro regressed with high correlative coefficients to establish a 3810-193, Portugal 4 prediction model suitable for the resource estimation of oil Institut für Mineralogie, Universität Münster, Corrensstr, 24, cracked gas. The verification formula for this model was also 48149 Münster, Germany established on the principle of mass conservation. The mineral and geochemical studies are carried out on a profile through a diagenetic methane-derived authigenic carbonate sample which was collected from southwestern Dongsha area of the northern South China Sea. The five samples located in the cross-sectional middle mainly consists of dolomite and quartz, and two samples close to surface show small amounts of Mg-calcite. The "13C, "18O and "44/40Ca values of the samples range -30.59‰~-0.30‰ VPDB, 3.07‰~3.59‰ VPDB and 1.35‰~1.47‰ SRM915a, 1. Fault 2. Well 3. Boundary of sedimentary facies respectively, indicating a clear contribution of methane 4. Content contour of solid bitumen in reservoir (%) oxidation to the carbon pool from which the authigenic 5. Distribution area of solid bitumen in reservoir carbonates precipitated from. From the isotope signals alone it Fig1.Content contour of solid bitumen in reservoir in NE can not be distinguished if the carbon source is rather Sichuan Basin thermogenic gas or a mixture of biogenic methane and marine The affecting factors and the application preconditions of dissolved inorganic carbon (DIC). The "18O values are in this model were discussed. Finally the model was extrapolated general consistent with dolomite precipitation from a fluid to the prediction of oil cracked gas resources of Feixianguan similar to present seawater. The observed small variability formation in NE Sichuan basin, SW China[1]. The prediction 12 3 might be related to fluid oxygen isotope composition. The value of oil cracked resources is about 6.84"10 m , and 8 relative small range in calcium isotope values indicates generation intensity of oil cracked gas is about 97.5"10 3 2 8 relatively constant growth conditions and precipitation from m /km , and the paleo-oil reserves is about 97"10 t. The seawater like fluid. The central part of the carbonate nodule verifying value for this prediction is approximately equal to 1, formed under the strong influence of methane seepage, and the indicating the model is reliable in the resource estimation of external part is less influenced by methane, either due to oil cracked gas. reduced methane flux to the surface or caused by erosional It is the first attempt to evaluate oil cracked gas resources exhumation of the carbonate nodule from greater depth to the through analyzing the increase or decrease of gas, liquid, and sediment surface. solid products in crude oil pyrolysis and the correlativity among the three yields. Acknowledgments: This study was supported by CAS Some new ideas are provided for the estimation of natural (KZCX2-YW-GJ03-01), NSFC (41276050, 41176052), 973 gas resources and the restoration of paleo-oil accumulations in Program (2009CB219502-4). the areas with high and overmature marine source rocks in south China. It is significant for the decision-making of natural gas exploration in China.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2456 Goldschmidt2013 Conference Abstracts

Geochemistry and isotope Provenance of Eolian Deposits in geochemistry of Upper Cretaceous Desert-Loess Transition, North China chalk as equivalent for reservoir by using Nd-Sr isotopic tracers chalk of the North sea Basin for EOR WANG XIAO*, AND RAO WENBO2, W. WANG1, M. V. MADLAND1, U. ZIMMERMANN1, Institue of Isotope Hydrology, School of Earth Sciences and S.A.R. BERTOLINO2, T. HILDEBRAND-HABEL3 AND R. I. Engineers, Hohai University, Nanjing, 210098, China KORSNES1
correspondence:[email protected])

1Univ. i Stavanger, IPT, Norway, [email protected] The desert-loess transition of China is very sensititive to 2CONICET-FAMAF, Cd. Universitaria, Córdoba, Argentina 3 climate change. Many studies on desert evolution and loess IRIS, P.O. Box 8046, 4068 Stavanger, Norway formation have been carried out in recent years[1]. However,

the provenance of late Quaternary deposits in the desert-loess Upper Cretaceous chalk from five exposures (Kansas, transition is not yet known. Here, we present Nd-Sr isotopic USA; Liège and Mons, Belgium; Aalborg and Stevns Klint, data of coarse-grained sands in the Dishaogouwan (DSGW) Denmark) have been sampled for comparison with reservoir profile in the transition between Ordos deserts and Chinese chalk of the North Sea Basin (Tor and Hod Formations at Ekofisk, Brynhild, Enoch, Sleipnir and Jotun fields) of similar Loess Plateau to identify the source of eolian deposits during the past 20ka. porosity in order to understand its reaction in flooding The DSGW profile mainly consists of Dishaogouwan experiments for enhanced oil recovery (EOR). Chalks from Stevns Klint and Mons are very pure and contain like samples (DSGW), Dagouwan (DGW), Chengchuan (CC), Salawusu from Aalborg only few amounts of clastic material. The latter (SW) and Lishi (LS) Formations. The Salawusu Formation has abundant diagenetic chert. Liège and Kansas chalk contain was aqueous but other formations were predominantly of & 87 86 the highest amount of clastics. Kansas chalk is particular, as it eolian origin. Nd(0) values and Sr/ Sr ratios of coarse- has reached the highest diagenetic grade, has higher grained fractions vary from -8.4 to -12.5 and from 0.7169 to concentrations in trace metals like Fe, Ni, Pb, Zn, Cu than all 0.7199 in DSGW and DGW, from -9.1 to -11.5 and from other chalk types and shows disturbed O-isotopes. This can be 0.7179 to 0.7192 in the CC, from -10 to -12 and from 0.7188 explained by abundant secondary micritic and sparitic cement to 0.7206 in SW and from -10.5 to -12.7 and from 0.7183 to in foraminifer shells. In contrast, C-O isotope values for all 0.7190 in LS, respectively. other on-shore chalk samples reflect primary seawater 80% ~ 90% of the eolian deposits developed in different periods were coarse-grained fractions. &Nd(0) values and composition. This cannot be found in reservoir chalk. Here, O- 87 86 isotopes are disturbed and similar to samples from Kansas. In Sr/ Sr ratios of coarse-grained in the Formations which were some fields (Sleipnir and Jotun fields) trace metal dominated by eolian deposits vary within a narrow range, compositions are also enriched and the chalk contains slightly implicate for a similar source. Furthermore, the coarse-grained higher amounts of clastic materials (Zr & Rb concentrations 2- fractions merely sprang and rolled on the earth’s surface by 5% of typical upper continental crust) and generally higher the wind[2]. So, eolian deposits in these Formations might be %REE concentrations with lower Y/Ho ratios (29-44) than in fed by sediment blowing of adjact highland or mechanical all on-shore samples. A post-depositional process affected the weathering of the sandstones in Ordos. Contrastly, the reservoir chalk, hence, in disturbing the O-isotope signature aqueous deposits of SW was dominated by fine-grained and affecting slightly the REE pattern, which is not related to fractions, and water erosion of underlying depoists probably dominated coarse aqeous deposits of sw. &Nd(0) values and clastic input. Chalk from Kansas shows a higher diagenetic 87 86 overprint which explains the re-setting of the O-isotopes, but Sr/ Sr ratios of coarse-grained in SW don’t have a obvious for the re-setting of the O-isotopes in reservoir chalk a reason difference with the values of eolian deposits. However, there are rarely coare-grained fractions in Loess plateau from where have still to be found. salawusu valley originated. So underlying eolian deposits with

abundant coarse-grained fractions could supply the aqueous

deposits with coarse-grained fractions.

[1] Sun et al. (1996) Marine Geology & Quaternary Geology 16(1), 23-31 [2] Chen et al. (1999) J. Sediment Res. 6, 84-89

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2457

In-situ observations of liquid-liquid The distribution of DBT and DBF in immiscibility in the system MgSO4- Mesoproterozoic (1.36 Ga) sediments 1 1 1 H2O (D2O) X.M. WANG , H.J. WANG AND S.C. ZHANG * XIAOLIN WANG 1, 2 AND WENXUAN HU 1, 2 1Research Insttitute of Petroleum Exploration & Development, 1 CNPC, Beijing 100083, China ([email protected], School of Earth Sciences and Engineering, Nanjing [email protected], *correspondence: University, Nanjing, 210093, P.R. China [email protected]) 2Institute of Energy Sciences, Nanjing University, Nanjing, 210093, P.R. China Previous studies of polycyclic aromatic hydrocarbons Liquid-liquid immiscibility has been documented in considered dibenzofuran (DBF) and dibenzothiophene (DBT)

aqueous UO2SO4 solutions at temperatures up to 468 ºC [1]. to be derived from phenolic compounds of lignin from woody Recently, we reported our observations on the liquid-liquid plants, thus their occurrence was attributed to terrestrial [1] phase separation in vapor-saturated aqueous MgSO4 solutions organic matter input . However, in our recent works in North at temperatures up to 350 ºC [2]. Under these conditions, we China Craton, high contents of DBF and DBT were both

observed that MgSO4-rich droplets were separated from the detected in the Mesoproterozoic (1.36 Ga) low mature

original aqueous MgSO4 solutions during heating, and these mudstones and shales. No matter how high of the total organic two coexisting liquid phases homogenized during cooling. It carbon contents in the shales, the distribution of DBF and has been found that the phase separation temperature DBT were more likely to be controlled by the paleoredox

decreases from 304.5 ºC to 259.5 ºC as MgSO4 concentration conditions (Figure 1). DBT had a peak abundance in the increases from 1.19 % to 19.36%. The newly discovered anoxic zone, while DBF was enriched in the oxic minimum

liquid-liquid phase separation in MgSO4 solutions was zone, the transition zone from oxic to anoxic. When the redox characterized by a lower critical solution temperature conditions changed to oxic, a dramatic decrease was happened phenomenon, which was considered to be a macro-scale in the abundances of DBF and DBT. Thus, we speculated that chemical property of polymeric mixtures. the abundance and distribution of DBT and DBF in ancient To further characterize the properties of the immiscible sediments may be controlled by the dynamic sulfic-oxic

fluids in the system MgSO4-H2O, we documented in-situ conditions. Raman spectroscopic investigations and observed a distinctly 2- -1 new #1(SO4 ) mode at ~1020 cm in the MgSO4-rich droplets; 2- the new #1(SO4 ) mode was predicted to be present in MgSO4 polymer(s) in aqueous solutions. As mentioned above, both the phase behavior and relevant Raman spectra indicate the

existence of polymer(s) in MgSO4 solutions. 2- We compared the new #1(SO4 ) mode with that of MgSO4-rich droplets in the system D2O-MgSO4. We found

2- -1 Depth(m) that there was also an #1(SO4 ) mode at ~1020 cm . This

observation suggests that the polymer(s) in aqueous MgSO4 solutions is not bonded through H2O and is probably contact ion pair chain(s), although the exact structure of the polymer(s) is still unknown. In addition, we investigated the hydrogen-bonds in the immiscible fluids. We found that the

MgSO4-rich fluids has higher potential for the preservation of

hydrogen bonds compared with that in the MgSO4-poor fluid Figure 1: The distribution of DBF and DBF in at the same temperature. This can be ascribed to the formation Mesoproterozoic low mature mudstones and shales. 2- of hydrogen bonds between SO4 and water molecules 2- because the probability of collision of H2O with SO4 in [1] Fenton et al. (2007) EPSL 262, 230-239. MgSO4-rich fluid is higher than that in the MgSO4-poor fluid.

[1] Marshall et al. (1962) J. Inorg. Nucl. Chem. 24, 889-897. [2] Wang et al. (2013) Geochim. Cosmochim. Acta 103, 1-10.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2458 Goldschmidt2013 Conference Abstracts

Age, geochemistry, and origin of Rare earth elements in hydrothermal Proterozoic rapakivi granites in the fluids from Kueishantao, off North Qaidam Orogen, NW China northeastern Taiwan XIAOXIA WANG1, NENGGAO HU2 AND TAO WANG3 XIAOYUAN WANG1 AND ZHIGANG ZENG1 1 Institute of Mineral Resources, Chinese Academy of 1 Key Laboratory of Marine Geology and Environment, Geological Sciences, Beijing 100037, China Institute of Oceanology, Chinese Academy of Sciences, 2 Chang’an University, Xi’an 710054, China Qingdao, 266071, China 3 Institute of Geology, Chinese Academy of Geological (*correspondence:[email protected]) Sciences, Beijing 100037, China The %REE concentrations of Kueishantao hydrothermal Proterozoic rapakivi granites are mainly distributed within fluids are 813-1212 ng/L, 1-2 orders of magnitude higher than craton in the Northern Hemisphere. However, Proterozoic those of seawater (%REE of shallow seawater is 92 ng/L; (ca.1770Ma) rapakivi granites have been recognized from the %REE of deep seawater is 14 ng/L), but are lower than they North Qaidam Orogen, the west segment of the Central are in most deep-sea hydrothermal fluids [1] and acidic hot Orogenic Systems of China. These granites exhibit typical waters in continental geothermal fields [2-4]. The difference rapakivi texture. They are A-type granite characterized by may be caused by the low leaching efficiency under the

high FeOt/(FeOt + MgO) and Ga/Al ratios, and SiO2, Na2O + seafloor due to the short duration of fluid-andesite interaction

K2O and rare earth element (except Eu) contents. Their whole- in the Kueishantao hydrothermal field [5].

rock #Nd(t) (–6.09 to –5.74 ) and zircon #Hf(t) ((9.4 to (2.8) The REEN distribution patterns of the yellowish fluids values, similar to those of the Proterozoic rapakivi granites in (108, pH)2.6, the flux is 35 m3/h ) show a slight North China Craton (NCC), indicate they were derived from enrichment of LREE and a slight convex-downward curvature old continental crust. These granites contain magmatic at Eu. The whitish fluids (51, pH)4.9, the flux is 19 m3/h)

microgranular enclaves and are intruded by diabases. The have REEN distribution patterns that exhibit a higher enclaves (more felsic) and granites show a uniform decrease enrichment of LREE than those of the yellowish fluids and in TiO2, CaO, Na2O, K2O, FeO, and MgO with increasing without Eu anomalies. The REEN distribution patterns of

SiO2, and similar trace element patterns but different whole- Kueishantao fluids are different from those of shallow

rock #Nd(t) values. The diabases and other enclaves (more seawater (generally flat with a negative Ce anomaly), deep-sea basic) deviate from the trend and have high whole-rock #Nd(t) acid-sulfate fluids, the acid-sulfate fluids in Taiwan Tatun values (ca. +4), suggesting their derivation from mantle. All volcanic area and other acid-sulfate hot waters in continental these features indicate that the granites are almost the same as geothermal fields. The Eu anomalies of Kueishantao the Proterozoic (ca. 1700 Ma) rapakivi granites in NCC and hydrothermal fluids are controlled mainly by the lower belong to the Proterozoic rapakivi granite suit in the Northern temperature and relative oxidizing conditions. The Hemisphere. They were involved in the Paleozoic North fractionation between LREE and HREE of the yellowish Qaidam orogen. It is first time to recognize Proterozoic fluids is influenced mainly by the very low pH and the rapakivi granites in Phanerozoic orogens. This also reveals precipitation of native sulfur. In contrast, the LREE/HREE that Precambrian craton in North China were strongly ratios of the whitish fluids may be related to the adsorption by destructed and reworked during Phanerozoic. small sulfur particles.

[1] Zeng (2011) Beijing: Science Press, 289-300. [2] Bau et al. (1998) Chem Geol, 293-307. [3] Sanada et al. (2006) Geothermics, 141-155.[4] Wood(2006) J Geochem Explor, 424-427.[5] Chen et al. (2005) Acta Oceanol Sin, 125-133.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2459

Nitrogen isotopes of coral skeleton- Cokriging estimation of soil bound organic matter: heavy-metal data obtained from Proxy evalution at Bermuda portable X-ray fluorescence XINGCHEN T. WANG1*, ANNE L. COHEN2 spectrometry 1 AND DANIEL M. SIGMAN 1 1 1 XIN-HAI WANG , KYOUNG-HO KIM , HO-RIM KIM , 1Department of Geosciences, Princeton University, Princeton SANG-IL HWANG2, HYEONG-DON KIM3 AND SEONG- NJ 08540, USA [email protected] (*presenting TAEK YUN1* author); [email protected] 1 Korea University, Department of Earth and Environmental 2Department of Marine Geology and Geophysics, Woods Hole Sciences and KU-KIST Green School, Seoul, South Oceanographic Institution, Woods Hole, MA, 02543, USA Korea, [email protected] [email protected] (* correspondence) 2 Korea Environment Institute (KEI), Seoul, South Korea Nitrogen isotopes of organic matter bound in coral 3 Seoul National University, National Instrumentation Center skeleton (hereafter, skeletal "15N) have the potential to be a for Environmental Management, Seoul, South Korea high-resolution proxy for the marine nitrogen cycle. By adapting a previously developed foraminifera-bound "15N Portable X-ray fluorescence spectrometry (P-XRF) is method, we have developed a sensitive method for measuring currently used as a cost-effective and rapid analytical tool for coral skeletal "15N, requiring 5 mg of skeleton powder and assessing the heavy metal pollution of soil. However, the in- yielding a precision of ~0.2‰. We evaluated the natural situ measured data are frequently unreliable due to soil variability of this proxy in Bermudan brain corals. Ten live heterogeneity, which may result in a difficulty to accurately coral colonies (Diploria labyrinthiformis) from four locations interpret the spatial patttern of pollution status. This study is around Bermuda were collected in 2005 and analyzed for purposed to evaluate the feasibility of P-XRF to obtain a skeletal "15N (Fig. 1). Skeletal "15N showed good reliable auxiliary dataset for the cokriging interpolation of soil reproducibility (< 0.5‰) among different colonies at the same heavy metal data. For this study, we used analytical results of location, suggesting coral skeletal "15N is a reliable proxy for arsenic concentrations in soil samples (n=156) from a metal- the local nitrogen cycle. Among the four sampling sites, polluted site, which were obtained by the conventional skeletal "15N decreased with distance from the island, from chemical leaching method and P-XRF. The both arsenic levels ~6.8‰ (inshore, Tynes Bay) to ~3.8‰ (offshore, HOG Reef). 2 showed a good correlation (R = 0.72). The true As pollution The annual calcification rate of each colony was estimated map was initially established by an ordinary kriging of 156 from image analysis of 3-D CT scans. Skeletal "15N at each data. Then, one third of the total samples (i.e., 52 P-XRF data) site exhibits a strong, negative correlation with annual were randomly chosen to presume the virtual soil calcification rate (R2>0.9). We propose that the efficiency of investigation, and two kinds of pollution maps were nutrient recycling between the symbionts and coral host is constructed using the ordinary kriging and cokriging methods. reduced when nutrient concentrations of reef seawater are Comparison of the estimated As levels with the true data at elevated, resulting in higher skeletal "15N and lower total sampling points (n=156) showed that the cokriging map calcification rates at our inshore sites. is more reliable (R2 = 0.89) than the ordinary kriging map (R2

= 0.40). This study shows the advantage of the cokriging Figure 1 interpretation of P-XRF data to evaluate the spatial Sample distribution of heavy metal pollution of soil. locations and

mean coral skeletal "15N

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2460 Goldschmidt2013 Conference Abstracts

Study on uranium speciation in the Holocene changes in fire frequency in water of a river near phosphate the Daihai Lake region (north-central mining area China): Indications and implications XIN-YU WANG1, 2, ZE-MING SHI1, 2 AND SHI-JUN NI1, 2,* for an important role of human 1Department of Geochemistry, Chengdu University of activity Technology, Chengdu, 610059, China; 1 1 1 2 XU WANG , LINLIN CUI , JULE XIAO Key laboratory of Nuclear Techniques in Geosciences, 1 AND ZHONGLI DING Chengdu 610059, China (E-mail: [email protected]; [email protected]; 1Key Laboratory of Cenozoic Geology and Environment, [email protected]. ) Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing, 100029, China; Uranium is a toxic and radioactive element for human ([email protected]) health. Previous research has revealed that those people who lived in the phosphate mining affected zone, had higher Black carbon (BC) content in a sediment core from Daihai concentration of uranium in blood than those who lived in Lake, Inner Mongolia, was analyzed to reconstruct a high- urban area. Based on the investigation of uranium resolution history of fires occurring in northern China during concentration in a river which flowed through phosphate the Holocene and to examine the impacts of natural changes mining affected zone, the speciation of uranium in the water and human activities on the fire regime. The black carbon was discussed in detail. mass sedimentation rate (BCMSR) was disintegrated into two In this paper, the potential, temperature and pH value were components: the background BCMSR and the BCMSR peak, in situ analysed. The concentrations of uranium, other cations with the BCMSR peak representing the frequency of fire and anions were respectively determined by ICP-MS, ICP- episodes. Both the background BCMSR and the magnitude of OES and IC. According to the above experimental data, the the BCMSR peak display a close relation with the percentage uranium speciation model was constructed. The results show of tree pollen from the same sediment core, suggesting that that: regional vegetation type would be a factor controlling the In nearly-neutral pH value range, the uranium speciation intensity of fires. The inferred fire-episode frequency for the distribution in water was mainly controlled by the phosphate Holocene exhibits two phases of obvious increases, i.e., the concentration of the water. The MUS (major uranium first increase from <5 to ~10 episodes/1000 yrs occurring at speciation) of the river near the phosphate mining affected 8200 cal. yrs BP when the vegetation of the lake basin shifted 2- 2- zone was UO2(HPO4)2 , while the MUS were UO2(CO3)2 and from grasses to forests and the climate changed from 4 - UO2(CO3)3 in water which near the cement factories. When warm/dry to warm/humid condition, and the further increase the river flowed through a farmland where the phosphate to a maximum frequency of 13 episodes/1000 yrs occurring at fertilizer was being used, the MUS in the water was 2800 cal. yrs BP when herbs and shrubs replaced the forests in 2- UO2(HPO4)2 . But after that site, the MUS of the river the lake basin and the climate became cool/dry. Both increases 2- 4- changed into UO2(CO3)2 and UO2(CO3)3 because of the in the fire frequency contradict the previous interpretation that increase of pH value and phosphate concentration. In this fires occurred frequently in the monsoon region of northern process, We found the use of phosphate fertilizer would lead China when steppe developed under the cold/dry climate. We to a significant increase of the phosphate concentration in the thus suggest that human activities would be responsible for the river. Moreover, the increasing of the phosphate concentration increased frequencies of fires in the Daihai Lake region in resulted in the hydrolysis of the anion and led to the raise of terms that the appearance of early agriculture and the pH value of the river. Some studies about the relationship expansion of human land use were considered to take place in between the uranium toxicity and its speciation revealed that, northern China at ca 8000 and 3000 cal. yrs BP, respectively. because of the biological preference of element Phosphorus, the speciation of uranyl phosphate had stronger cytotoxicity (bioavailability) than the common speciation of uranyl carbonate.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2461

Early Archean ultra-depleted mantle: Silicate melts under high pressure Evidence from newly discovered ~3.8 YANBIN WANG1, TATSUYA SAKAMAKI1, *, Ga trondhjemite in North China LAWRIE SKINNER2, GUOYIN SHEN3, TONY YU1, YOSHIO KONO3, ZHICHENG JING1 AND CHANGYONG PARK3 1 1 2 YAFEI WANG *, XIANHUA LI , WEI JIN 1 2 Cnter for Advanced Radiation Sources, the University of AND JIAHUI ZHANG Chicago, Chicago, IL, USA 1Institute of Geology and Geophysics, Chinese Academy of 2Stony Brook University, Stony Brook, NY, USA Sciences, Beijing, 100029, China (*correspondence: 3HPCAT, Carnegie Institution of Washington, Argonne, IL, [email protected]; [email protected]) USA 2College of Earth Sciences, Jilin University, 130021, China We present our recent data on structural evolution of The scale and degree of early mantle depletion and silicate melts and glasses at high pressures, along with continental crust growth are poorly constrained because measurements of density, elasticity, and viscosity. High- isotopic systems of ancient rocks are susceptible to later pressure melt structure studies were conducted using a Paris- disturbances and most reliable Hadean to Archean zircons Edinburgh Press at the HPCAT beamline 16-BM-B. Acoustic exhibit enriched isotopic characteristics. velocities were also measured on silicate glasses. A DIA Detailed field and zircon isotopic studies show that our apparatus was used for melt density measurements based on x- newly discovered ~3.81 Ga trondhjemite was enclosed by ray absorption at GSECARS beamline 13-BM-D. Structures

~3.36 Ga migmatite complex, and variable younger ages due of polymerized (jadeite – NaAlSi2O6) and depolymerized

to various degree of ancient radiogenic Pb loss, intrusion of (diopside, CaMgSi2O6) melts show distinct responses to leucosome, and a possible new ~3.31 Ga crustal growth event. pressure. In jadeite melt, T-O (T denotes tetrahedrally The concordant (disc.<5%) ~3.8 Ga zircons with simple coordinated Al and Si) bond length, T-T bond length, and T- oscillatory zonings preserve the primary isotopic signatures, O-T angle all exhibit rapid and non-linear decrease with 18 ranging in $Hf values from -1.9 ± 0.9 to 6.2 ± 0.7 and ! O increasing pressure to ~3 GPa. In diopside melt, these from 5.3 ± 0.3 to 7.0 ± 0.3‰. The extremely positive $Hf parameters vary linearly with pressure and change very little. values exceed values of previously reported contemporaneous A large viscosity dataset from the literature shows that, with zircons and existing depleted mantle Hf isotopic evolutionary increasing pressure, viscosities of polymerized liquids models at ~3.8 Ga, providing robust isotopic evidence for the (including jadeite) first decrease and reach a minimum at existence of an ultra-depleted mantle source corresponding to around 3 GPa before turning over. On the other hand, significant crustal growth at least 3.8 Gyr ago. viscosities of depolymerized melts (including diopsite) increase monotonically with pressure. Molecular dynamics calculations, constrained by the x-ray structural data, were employed to examine details of structural evolution in the two types of liquids. A model will be presented to link structural evolutions to changes in melt properties, such as density and viscosity, with pressure.

Figure 1: Plot of #Hf(T) versus age of disc.<10% zircons in ~3.81 Ga unit with putative reservoirs differentiated at 4.5 Ga

and details of two highest #Hf zircons. The highest #Hf value requires a reservior with 176Lu/177Hf ratio of 0.049, significantly higher than present-day depleted mantle value of 0.0384, differentiated at 4.5 Ga. The blue circle is ~60%m in diameter.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2462 Goldschmidt2013 Conference Abstracts

Oxygen isotope compositions of Al- Geochemical characteristics of rich chondrules from carbonaceous different type reservoirs from the chondrites Sinian Dengying Formation in Y. WANG1*, W. HSU1, X. LI2, AND Q. LI2 Southeastern Sichuan Basin, China 1Purple Mountain Observatory, Chinese Academy of Sciences, WANG YONG AND SHI ZEJIN2 Nanjing 210008, China (*correspondence: 1 Department of Geochemistry, Chengdu University of [email protected]) Technology, Chengdu 610059, China; e-mail: 2Institute of Geology and Geophysics, Chinese Academy of [email protected] Sciences, Beijing 100029, China 2 State Key Laboratory of Oil and Gas Reservoir Geology and

Exploitation, Chengdu University of Technology, Al-rich chondrules (ARCs) are rare objects with >10 wt% Chengdu 610059!China; e-mail: [email protected] bulk Al2O3 content. They have petrological, chemical, and oxygen isotopic characteristics intermediate between Ca,Al- Reservoirs in Sinian Dengying Formation can be divided rich inclusions (CAIs) and ferromagnesian chondrules (FMCs) into three categories according to genesis, that is, paleo-karst [1]. ARCs are an unique window to study the orgins of CAIs reservoirs related to tectonic uplift, buried dissolution and chondrules and their genetic relationship. reservoirs due to burial and dissolution and hydrothermal Eleven ARCs and representative CAIs and FMCs from dolomite reservoirs. Compared with surrounding rocks in three CV3 (NWA 2140, NWA 2697, and NWA 989) and Dengying Formation, paleo-karst reservoirs had the Ningqiang chondrites were studied. Olivine, pyroxene, characteristics of low Na, high Mn, high Fe, low Sr, low plagioclase, spinel, and Si,Al-rich glasses were analyzed with 87 86 carbon isotope and high Sr/ Sr value generally reflecting the Cameca ims-1280 ion microprobe, housed at IGG, Beijing. the fact that the formation of paleo-karst reservoirs was The oxygen isotope compositions of ARCs form a mixing line closely related to fresh water. Buried dissolution" reservoirs with a slope of 0.86±0.04 (Figure 1), close to the CCAM line had the characteristics of high Mn, low Fe and low carbon (slope=0.94) [2]. ARCs have &17O values (0.3~-17.9 ‰) isotopes. The characteristics of high Mn indicated that buried intermediate between CAIs (-1.4~-27 ‰) and FMCs (2.4~-9.8 dissolution reservoirs experienced stronger diagenesis ‰), indicating that the precursors of ARCs might be mixtures modification in the burial environment, while low Fe and low of CAIs and FMCs. Minerals in individual ARCs are carbon isotopes were related to dissolution effects of organic heterogeneous in oxygen isotope compositions, with the acids during burial. Hydrothermal dolomite reservoirs had biggest &17O variation of 15.4 ‰. This imples that during the very low contents of Fe and Sr element, significantly partial formation of ARCs, oxygen isotopic exchange with nebular negative oxygen isotope, and very high 87Sr/86Sr value. The gases might have occurred. formation of these characteristics was related to hydrothermal physical and chemical properties. Three major types of reservoirs in Dengying Formation had significant geochemical response characteristics, which could be taken as geochemical indicators to identify different types of reservoirs.

Figure 1: Oxygen isotope compositions of ARCs from Ningqiang and three CV3 chondrites. [1] Krot & Keil (2002) MAPS 37, 91-111. [2] Yurimoto et al. (2008) in Rev. in Min. & Geochem 68, 141-186. This work was supported by the National Natural Science Foundation (41003026) and the Minor Planet Foundation of China.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2463

Lawsonite as a potential repository of Mercury biogeochemistry and its Th and REE in subduction zones: biomagnification in the fish food web Blueschists from Tav"anlı (Turkey) in Three Gorges Reservoir after Y. WANG1, D. PRELEVI*1, S. FOLEY1,2, S. BUHRE1, 175m impoundment 1 1 T. JOHNSON AND T. HÄGER 1 2 A 1 YUCHUN WANG MEI MA AND YANG YU 1Uni Mainz, Mainz, Germany ([email protected]) 1Department of Water Environment, China Institute of Water 2CCFS, Dept. Earth and Planetary Sciences, Macquarie Resources and Hydropower Research, Beijing 100038, University, North Ryde, NSW 2109, Australia China. [email protected]; [email protected]

2State Key Laboratory of Environmental Chemistry and Constraining the processes by which crust is recycled back Ecotoxicology, Research Center for Eco-Environmental through the mantle wedge and into volcanic arcs is one of the Sciences, Chinese Academy of Sciences, Beijing 100038, most challenging issues in modern geochemistry. Discussion China. [email protected] is mostly centered around the dichotomy of fluid vs melt transport and subsolidus dehydration vs melting, in which the Three Gorges Reservoir (TGR) is a giant canyon-shaped mobility of Th and REE has particular significance. In this reservoir located in the lower section of the upper reaches of context, production of fluid or melt by breakdown of hydrous the Yangtze River. Concern about human consumption of fish minerals such as lawsonite, and the consequences for trace contaminated with MeHg had been raised even before the element mobilization remain largely unconstrained. construction of TGR. This study tried to investigate the total Here we combine EMP, LAM-ICP-MS and confocal mercury concentrations in fish and biomagnification microRaman spectroscopy with THERMOCALC modelling of characters of mercury along food chains in TGR after 175m four samples of lawsonite and garnet bearing blueschist from impoundment. We collected eleven fish species from three the Tav+anlı Zone, Turkey, a melange metamorphosed under main stem sections and seven typical tributaries of TGR from blueschist to lawsonite-eclogite facies conditions. Our aim 2011 to 2012. Result showed that mercury concentrations in was to monitor trace element redistribution during high- fishes from TGR had not obviously increased after pressure–low-temperature metamorphism. Two samples have impoundment. But spatial difference was found among low concentrations of Th, REE and K, suggesting an different sections of main stem. Due to the enhanced sediment essentially oceanic crust protolith, while the other two samples deposition along reservoir, there was a decreasing trend of are enriched in K (up to 2.89% K O), Th and REE, implying 2 mercury concentration in fish from upper stream to lower the presence of a continent-derived terrigenous component. stream within TGR. Mercury concentrations in the fishes from Equilibrium assemblages are lawsonite + glaucophane + Luoqi in up area of reservoir (88.0%g/kg, average) was chlorite + phengite + titanite + apatite +/- garnet +/- quartz and significantly higher than those from Wushan in middle area of iron oxides. Garnet is the major host for HREE, phengite reservoir (43.1%g/kg, average) and tributaries (57.1%g/kg, contains most LILE and titanite and zircon are the dominant average). The mercury concentrations in fish from tributaries carriers for Nb, Ta and Zr, Hf, respectively. Lawsonite and were comparable to those from main stem, and there were no apatite carry almost all Sr and a significant proportion of the significant difference among most tributaries. While Log- REE. In Th rich samples, lawsonite is extremely enriched (up transformed mercury contents were consistently correlated to 100 ppm) in Th, giving rise to high Th/La ratios up to 1.0, 15 with " N values for the fish food web in all sampling sites, at relatively low Sm/La (down to 0.4). 15 the slope of the relationship with " N (biomagnification The high Th/La ratios observed in lawsonite are power value) was significant higher in Shennong River than significantly higher than in average crust and normal arc that in Wanzhou and Wushan section. This indicated that volcanics, but similar to those in Mediterranean lamproites, biomagnification power of mercury is greater in tributary than rare ultrapotasic orogenic lavas occurring within Alpine- in main stem of TGR. Data of "15N and "13C showed that Hymalayan belt. This “fingerprint” may result from the fishes in tributary rely more on pelagic primary production incorporation of lawsonite-bearing blueschists into their while those in main stem tend to take allochthonous materials melting source, and subsequent melting. High Th/La can be carried by runoff. In conclusion, the difference between body liberated only by direct melting, ruling out prograde type of tributary and main stem after impoundment may be an recrystallization into new mineral phases, which redistribute important reason of different mercury bioaccumulation within trace elements differently. TGR.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2464 Goldschmidt2013 Conference Abstracts

Uranium(IV) mobility in a Nano pore evolutions of shale and mining-impacted wetland coal during petroleum generation Y. WANG1*, M. FRUTSCHI1, E. SUVOROVA1, process using SANS and pyrolysis 2 2 3 V. PHROMMAVANH , M. DESCOSTES , A. OSMAN , 1 2 A 1 YUNPENG WANG MEI DING AND LINGLING LIAO G. GEIPEL3 AND R. BERNIER-LATMANI1 1 SKLOG, Guangzhou Institute of Geochemistry, Chinese 1Ecole Polytechnique Fédérale de Lausanne (EPFL), Environmental Academy of Sciences, Guangzhou 510640, China Microbiology Laboratory, Lausanne, Switzerland (*presenting 2 EES-14, LANL, Los Alamos, NM 87545, USA author: [email protected]) 2AREVA - Business Group Mines, Direction R&D, BAL 3720C, Tour This study aims to examine the changes of nano- to AREVA, Paris, France microscaled pores of shale (marine and lacustrine) and coal 3Helmholtz Center Dresden Rossendorf (HZDR), Institute of Resource with petroleum generation, retaining and cracking. Pyrolysis Ecology, Dresden, Germany was used to define oil and gas window, as well as study the

compositions of expulsed and retained oil while small-angle Uranium is known to accumulate in wetlands through its neutron scattering (SANS) was used to characterize nano- to association with organic-rich soils. The precipitation of microscaled pores of residual source rocks. Oil windows are relatively insoluble U(IV) minerals under reducing conditions defined as 0.6-1.3%Ro for shale and 0.5-1.2%Ro for coal; wet is considered as a means to immobilize U in constructed gas window are 0.9-3.0% Ro for shale and 0.8-3.0% Ro for wetland systems [1]. A wetland in the Limousin region in coal; dry gas windows are 1.3-3.6%Ro for both shale and coal. France, located adjacent to a former U mine was impacted by In oil window, marine shale oil shows mainly saturated and mining activity for several decades and contains U hotspots aromatic fractions, resins and less asphaltene. In gas window, (~4,000 ppm) [2]. The concentration of U steadily increases as higher saturated fractions is due to its higher stability. Coal oil a function of distance in a stream flowing through the wetland, shows dominant asphaltene fraction with higher aromatic HC, suggesting U release from the wetland into the stream. We resin, asphaltene and rare saturated HC. collected soil and porewater samples under anoxic conditions Pore features corresponding to oil and gas windows by from two selected U hotspots in the wetland as a function of SANS show that shale and coal have unique pore features at depth and season to assess the geochemical conditions leading the scale between 1 to 100 nm. Results also show that pore to this release. High porewater Fe(II) concentrations suggest features change more significantly in coal relative to shale that metal-reducing conditions prevail in the wetland soil. rock during hydrocarbon generation and expulsion from Using laser fluorescence spectroscopy (LFS) and X-ray source rocks, presumably due to the much higher organic absorption spectroscopy (XAS), we concluded that the carbon content of the coal and unique HC fractional predominant U redox state in both porewater and soil was compositions (Fig. 1). tetravalent. A near constant U(IV) concentration is observed

throughout the porewater profile while soil U(IV) is restricted

to the top 30 cm. Evidence for U association with colloidal

Fe(OH) -organic matter assemblages provided a ready 2 explanation for the mobility of porewater U. Furthermore, U

in the soil occurs primarily as a non-crystalline U(IV) species

corresponding to U(IV) adsorbed onto amorphous Fe-Al-P-Si

aggregates. Hence, U(IV) species in the porewater are distinct

from those present in the soil. These results show that the form

of U(IV) in soil is labile and releases U(IV) to form mobile

colloids that ultimately result in the release of U into the

stream. The surprising mobility of U(IV) in this system brings

into question the often assumed immobilization of U through

reduction, particulalry in high organic matter environments

such as wetlands.

Figure 1 SANS plot of shale and coal in early oil window(L, [1] Owen et al. (1995) Ecol. Eng. 5, 77-93. [2] Moulin (2008) 0.4%Ro) and post gas window(H,3.8%Ro) as well as the PhD thesis, Ecole Centrale de Paris. corresponding hydrocarbon(HC) fractional compositions

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2465

Accretion of a volatile rich late Origin of deep gas and oil cracking veneer recorded by CI chondrite-like gas potential in Tarim Basin, China S/Se and Se/Te in the Earth’s mantle ZHAOYUN WANG1, YONGXIN LI2, AND HONGJU ZHENG3 ZAICONG WANG* AND HARRY BECKER 1 Research Institute of Petroleum Exploration and Development, Petrochina, Beijing, China, [email protected] Freie Universität Berlin, Malteserstrasse 74-100, 12249 2 Research Institute of Petroleum Exploration and Development, Berlin, Germany (*contact: [email protected]) Petrochina, Beijing, China, [email protected]

3 Research Institute of Petroleum Exploration and Development, The history of delivery of volatile elements is of Petrochina, Beijing, China, [email protected] fundamental importance for understanding planetary evolution

(Albered, 2009). The detailed origin and history of moderately The marine strata in China is of old age and in high volatile and atmophile elements in the Earth remains evolution period, and the potential of gas generated from high- uncertain. The excess of highly siderophile elements (HSE) overmature source rocks is limited, but the gas exploration of and chondritic ratios of most HSE in the bulk silicate Earth this marine strata in Tarim basin has greatly effective with (BSE) may reflect accretion of a chondritic late veneer of large gas fields constantly discovered. about 0.5 % of Earth’s mass after core formation[1,2]. The This paper brings up the successive gas generation proportion of volatiles delivered by the late veneer is a key machanism for the origin of deep marine gas, including three constraint for the budget and the origin of the volatiles in the meanings of transformation of gas generation matter, Earth. At high pressure-temperature conditions, the replacement of gas generation time,and change of gas source moderately volatile chalcogen elements S, Se and Te with kitchen. The gas source kitchen of dispersive liquid rather low 50 % condensation temperatures near 700 K are hydrocarbon inside of source rocks inherits the characteristics moderately to highly siderophile, thus, if depleted by core of original gas source kitchen, but the gas source kitchen of formation, their mantle abundances should reflect the dispersive & concentrated liquid hydrocarbon outside of composition of the late veneer[3]. Here we determined ratios source rocks has occurred the spacial change comparing with and abundances of S, Se and Te in the mantle based on new original gas source kitchen. The above three liquid isotope dilution data for post-Archean mantle peridotites with hydrocarbon can be cracked into gas at high-over mature negligible low-temperature alteration. Infiltration and trapping stage, but the latter is embeded flatter and its time of cracking of silicate melt in peridotites have very similar effects on and gas generation is later than the former, which makes for abundances of S, Se and Te as partitioning during open system the late gas accumulations. melting[4,5]. The mean S/Se (2690±700, 1') and Se/Te This paper creates expulsion oil rate plates of different (7.9±1.6, 1') of mantle lherzolites overlap with CI chondrite organic matter abundance through simulation experiments of values[6]. In contrast, Se/Te of ordinary and enstatite hydrcarbon generation and expulsion of different organic chondrites are significantly different (11-30)[7]. The matter abundance and different lithology source rocks, chalcogen/HSE ratio of the BSE is similar to CM group providing the basis for the reasearch of allocation proportion carbonaceous chondrites, consistent with the view that the and quantity of dispersive liquid hydrocarbon inside & outside HSE signature of the BSE reflects a mixture of slightly of source rocks. volatile depleted carbonaceous chondrite and minor non- This paper demonstrates the quantity, distribution and chondritic material[8]. Depending on the estimates for the cracking degree of dispersive soluble organic materials of abundances of water and carbon in the BSE (Marty 2012), the palaeozoic strata in Tarim basin from the evaluating indicator late veneer may have supplied a significant proportion of the S of hydrocarbon generating potential, heat-origin asphalt and budget of hydrogen and carbon in the BSE. 1 the fluorescence characteristic of reserviors, and makes sure of

the reality of successive gas generation of organic matter of [1] Albarède (2009), Nature, 461, 1227-1233. [2] Walker palaeozoic marine source rocks in Tarim basin, and also (2009) Chem Erde-Geo 69, 101-125. [3] Mann et al. (2012) calculates the cracking gas quantity of dispersive soluble GCA 84, 593-613. [4] Rose-Weston et al. (2009) GCA 73, organic matter in middle and lower Cambrian of Tarim basin. 4598-4615. [5] Wang et al. (2013) GCA 108, 21-44. [6] The application of successive gas generation mechanism of Lorand & Alard (2010) CG, 278, 120-130. [7] Lodders (2003) organic matter can greatly increase the gas exploration J Astrophys 591, 1220-1247. [8] Wasson & Kallemeyn (1988) potential and hopeness of palaeozoic strata in Tarim Phil Trans R Soc A 325, 535-544. [9] Fischer-Gödde & basin,China. Becker (2012) GCA 77, 135-156. [10] Marty (2012) EPLS,

313–314(0): 56-66. [1] Dai et al (2002) Xinjiang Petroleum Geology 23, 357-365. [2] Zhao et al (2005) Petroleum Exploration and Development 32, 1-7. [3] Liang et al (2000) Earth Science Frontiers 7, 534- 547. [4] Zhang et al (2002) China Petroleum Exploration 4, 18-24.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2466 Goldschmidt2013 Conference Abstracts

Novel calcite-aragonite sea transition Oxygen isotope equilibrium between in the terminal Proterozoic sulfite and water ZHENGRONG WANG1 JUSTIN AND RIES2 CHAO LIU1 SCOTT D. WANKEL*1,2, ALEXANDER S. BRADLEY1,3, 4 1 1 DANIEL L ELDRIDGE AND DAVID T. JOHNSTON* Department of Geology and Geophysics, Yale University, New Haven, CT, USA, [email protected] 1Dept. of Earth and Planetary Science, Harvard University, 2Department of Marine Sciences, University of North Cambridge, MA 02138 ([email protected]) Carolina, Chapel Hill, NC, USA, [email protected] 2Dept. of Marine Chemistry and Geochemistry, WHOI, Woods Hole, MA 02540 ([email protected]) Tectonically driven fluctuations in seawater Mg/Ca are 3Dept. of Earth and Planetary Science, Washington University, thought to have caused changes in the polymorph mineralogy St. Louis, MO 63130 of platform carbonates throughout Phanerozoic time 4Dept of Geology, Univ of Maryland, College Park, MD (Mg/Ca<2 = calcite seas; Mg/Ca>2 = aragonite seas) [1]. 20742 Previously published elemental analyses of micritic limstones from the terminal Proterozoic Nama Group (552-544 Ma), Application of the oxygen isotopic composition of sulfate 18 southern Namibia, show a threshold increase in Sr/Ca (by a (" OSO4) is complicated by rapid equilibration between factor of 6-7) from 549 to 547 Ma and a decrease in Mg/Ca sulfoxyanions and water. Specifically, the apparent 18 18 ratio (by a factor of 5) from 552 to 544, which are both relationship that develops between " OSO4 and " Owater during consistent with a transition from primary calcite limestones microbial sulfate reduction is thought to result from rapid (Sr-depleted, Mg-enriched) to primary aragonite limestones equilibrium between water and aqueous intracellular sulfite 2- (Sr-enriched, Mg-depleted) across this interval [2]. (SO3 ) – a reactive intermediate in the sulfate reduction To further investigate this potentially novel calcite- network. Here, we describe the oxygen isotope equilibrium 2- aragonite sea transition, we measured the Sr and Mg isotope effect between SO3 and water, based on experiments compositions of the Nama Group carbonates (552 – 544 Ma) conducted over a range of pH (4.5 to 9.8) and temperature (2 at Yale University. 87Sr/86Sr ratios are elevated from 0.7090 to to 90˚C). Experimental results are consistent with predicted 0.7105 between 552 and 549 Ma, and then decline to a values based on ab initio estimates of oxygen isotope relatively stable value of 0.7086 between 549 and 544 Ma.. equilibrium values among S(IV) species and water and 26 The bulk " MgDSM3 values of the carbonates increase steadily changes in speciation. We find that &sulfite-water = 13.61 – from ~ -2.5 to -1.2‰ between 552 and 544 Ma, with a brief 0.299*pH – 0.081*T˚C such that at a pH (7.0) and temperature excursion down to -3.5‰ at ca. 549 Ma, which coincides with (25˚C) typifying common experimental conditions of sulfate 87 86 2- 18 peaks in Sr/ Sr and Mg/Ca ratios. reducing bacterial cultures, SO3 is enriched in O by 9.5‰ Theoretical work and empirical observations of modern (± 0.8‰) relative to ambient water. By evaluating previously carbonates show that 26Mg is enriched in the following order: published data within an updated sulfate reduction network, low Mg calcite < high-Mg calcite < dolomite < aragonite [3]. results prove consistent with high enzyme reversibility in the Thus, the increase in "26Mg from 552 to 542 Ma is consistent sulfate reduction biochemical network. We show that -2 with an increase in the proportion of primary aragonite with intracellular SO3 exchanges with water up to 3 orders of time. Likewise, the decline in 87Sr/86Sr across the interval is magnitude faster than internal recycling and that kinetic 2- consistent with a transition from a lower-Mg/Ca calcite sea isotope effects upstream of SO3 are required to explain 18 characterized by increased hydrothermal flux of radiogenic Sr previous laboratory and environmental studies of " OSO4 (higher 87/86Sr), to a higher-Mg/Ca aragonitic sea characterized resulting as a consequence of sulfate reduction. by decreased hydrothermal flux of radiogenic Sr (lower 87/86Sr). High-frequency incremental leaching of a set of limestone samples also suggests that the anomalous peaks in 87/86Sr and Mg/Ca around 549 Ma may have resulted from localized diagenetic alteration.

[1] Hardie, LA, 1996, Geology 24: 279-283. [2] Ries, J et al. , 2009, Geology 37: 743-746 [3] Wang et al. , 2013, GCA, 102: 113-123

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2467

7 Seawater # Li: A tracer for global Noble gas partitioning in CO2 CO2 consumption by continental environments: a supercritical silicate weathering? assessment of current assumptions CHRISTOPH WANNER* AND ERIC L. SONNENTHAL O. WARR1*, A. MASTERS2, C. ROCHELLE3 AND C.J. BALLENTINE1 Lawrence Berkeley National Laboratory, Berkeley, CA, USA, (*correspondence: [email protected]) 1SEAES, University of Manchester, M13 9PL, UK (*correspondence: [email protected]) Lithium isotope fractionation has been used as a proxy for 2CEAS, University of Manchester, M13 9PL, UK silicate weathering and as a tracer in geothermal systems [1,2]. 3 British Geological Survey, Nottingham, NG12 5GG, UK Misra & Froelich [1] recently presented the first record of 7 Cenozoic seawater " Li showing an increase of 9‰ over the Noble gases are powerful inert tracers which can yield key last 60 Ma. This increase was attributed to increasing riverine information about physical processes occurring within 7 " Li values caused by a general change in continental silicate geological systems. Currently all modelling involving binary weathering behaviour. phase noble gas partitioning are based on the determinations Reactive transport modelling was performed using by Crovetto et al. 1982 [1] under conditions that did not TOUGHREACT [3] to gain insight into the geochemical and require consideration of phase composition, supercriticality isotopic effects of the changing weathering pattern. nor the effect of non ideality on solute noble gases. Simulations considered a granitic aquifer feeding a major river Subsequent studies have not investigated these factors; the system. Li isotope fractionation was assumed to solely occur validity of all current interpretations is based on the during Li incorporation into precipitating secondary minerals, assumption that these variables have no effect on noble gas computed using a solid solution approach [4]. Different partitioning. However, no published study exists which weathering patterns were simulated by varying the substantiates this supposition. Assessing the effects these contribution from weathering of unaltered granitic mineral variables have on partitioning will give us a much warranted phases (quartz, feldspars, micas), including the precipitation greater insight and understanding into geological systems that and dissolution of secondary minerals (kaolinite, chlorite) operate under significantly different PVTX conditions. using a dual continuum approach. We present noble gas partitioning results from a 7 Simulated " Li values increased with an increasing supercritical CO2–H2O binary phase system at elevated contribution from weathering of primary granitic mineral temperatures and pressures (50-100°C & 90-140 bar). This phases suggesting that today’s heavy riverine and seawater system was chosen due to a strong current interest in 7 " Li values are the result of a “weathering-limited” weathering underground storage of anthropogenic CO2 and their natural pattern such as proposed by Misra and Froelich [1]. In analogues for which noble gases have already proven 7 contrast, our simulations suggest that low " Li values inferred invaluable [2,3]. Partitioning is determined using a combined for the Paleocene-Eocene boundary [1] were largely inherited experimental and numerical simulation-based approach to from weathering of previously formed secondary mineral generate partitioning values which forms the basis of a robust phases associated with little or no Li isotope fractionation. model for predicting partitioning over a wide range of PT Moreover, total simulated CO2 consumption by silicate conditions. We present our methodology and results which we 7 weathering reactions are positively correlated with " Li values compare and contrast with values derived from the Crovetto et 7 suggesting that global riverine and seawater " Li values are al. dataset. Preliminary findings suggest noble gas

directly linked to the total amount of global CO2 consumption partitioning is demonstrably different for a supercritical CO2–

by continental silicate weathering. For a quantitative H2O system; overall water phase solubility is significantly correlation, however, more experimental work is needed to reduced, especially for the heavier noble gases by up to 60%. better understand Li isotope fractionation processes including This observed disparity appears greatest at higher pressures identifying key minerals involved and determining and lower temperatures although an observable difference is corresponding Li isotope fractionation factors. noted across the studied PT range.

[1] Misra & Froelich (2012), Science 335, 818-823. [2] Millot [1] Crovetto et al. (1982) J. Chem. Phys 76, 1077-1086. [2] & Negrel (2007), Chem. Geol. 244, 664-678. [3] Xu et al. Gilfillan et al. (2009) Nature 458 614-618. [3] Zhou et al. (2011), Comput. & Geosci. 37, 763-774. [4] Wanner & (2012) Geochim. Cosmochim. Acta 86 257-275. Sonnenthal (2013), Chem. Geol. 337-338, 88-98.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2468 Goldschmidt2013 Conference Abstracts

Global Abyssal Peridotite Constraints Long-term CO2 induced reactivity, on the Upper Mantle observations on natural CO2 JESSICA M. WARREN1 analogues and geochemical model 1Stanford University, 450 Serra Mall, Stanford, CA 93405; predictions [email protected] 1 1 LAURA J. WASCH , MARIELLE KOENEN 1 AND SUSANNE NELSKAMP Abyssal peridotites are the residues of adiabatic decompression melting beneath ridges. A broad sampling of TNO, Princetonlaan 6, P.O. Box 80015, 3508 TA Utrecht, the abyssal peridotites from all major ocean ridges reveals Netherlands. [email protected] variations in composition that reflect both ridge processes (melting, refertilization) and pre-existing heterogeneity. I Predicting CO2 trapping and containment over extended present a compilation of geochemical data for abyssal timescales asks for accurate models and well constrained input peridotites from 59 localities on 6 major ridge systems (EPR, parameters. CO2 natural analogues provide good opportunities MAR, SWIR, CIR, AAR, and Gakkel). While the majority of to study the actual long-term effect of CO2 on reservoir and peridotites have been sampled at transform faults, sampling at caprock. This will provide valuable insight in long-term slow and ultra-slow ridges in the past decade has recovered geochemical processes concerning CO2 storage. Moreover, large suites of on-axis peridotites. Compositional data has now natural analogues can help calibrate simulations of the long- been published for ~1500 peridotites, permitting a detailed term chemical effects of CO2 storage. Accurate simulations look at global variations in the oceanic upper mantle. are essential for confirming whether the observed and I classify peridotites into residual peridotites and four modelled behaviour of injected CO2 are in agreement, as types of veined peridotite: (1) gabbro-veined & plagioclase- required for EU regulations, thereby facilitating succesful bearing peridotite, (2) pyroxenite-veined peridotite, (3) dunite, implementation of CCUS. and (4) cryptically metasomatized peridotite. The veins are We present an integrated approach of petography, basin generally interpreted to represent incompletely extracted melt modelling and geochemical modelling. Our study is focussed or melt-related features retained in peridotite after adiabatic on the Werkendam natural analogue, a Dutch gas field decompression melting. Veined peridotites represent >30% of containing > 70% CO2. The CO2 was trapped milions of years the dataset. The abundance of veined peridotite indicates that ago and hence the reservoir has been reacting with CO2 for oceanic lithospheric mantle is less depleted than commonly prolonged periods of time. In addition to CO2 induced assumed, resulting in recycling of relatively more enriched reactions, reactions related to ‘ordinary’ diagenesis are material at subduction zones. expected to have occurred. To distinguish the effect of CO2 Residual peridotites provide the best representation of from diagenesis, the Waalwijk methane field was selected as a mantle composition following melt depletion and extraction. CO2 free reference of the same formation. Basin modelling However, these unveined, residual peridotites define a showed that this field has a comparable burial history as surprisingly large compositional range, particularly at some Werkendam. Samples from both reservoirs are studied with individual localities. Modal Cpx varies from 0 to 15%, while SEM to assess the differences in the mineral relations. spinel Cr/[Cr+Al] varies from 0.1 to 0.6. Individual trace Comparison of the reactions observed in the CO2 and the CH4 elements vary by one to three orders of magnitude, which fields points to differences in mineral dissolution and corresponds to ~0-12% degree of nonmodal fractional secondary carbonate formation. The presence of CO2 appears melting. Such variation is at odds with theory, which predicts to enhance feldspar dissolution while facilitating (additional) that the degree of melting beneath ridges should be relatively formation of carbonates such as siderite, dolomite and uniform, except at ultra-slow spreading rates. In addition, ankerite. Geochemical modelling with PHREEQC is some sections of ridge contain highly depleted peridotite performed to assess if these reactions associated with CO2 associated with thin or absent basaltic crust. Some local-scale correspond to the predicted mineral changes. Calibration of variability can be explained by incipient melt-rock reaction to the model indicates that the selection of primary mineralogy, produce dunite, but the pervasive variability at all length- especially the minor iron-bearing minerals, has a large effect scales indicates that regions of the upper mantle must contain on predicted CO2 mineralization. pre-existing heterogeneities. This agrees with isotopic data Detailed mineralogical input and assessment of the burial (available for <100 abyssal peridotites), which require long- history is required to calibrate geochemical models which will term depletions and enrichments in the mantle. increase our knowledge on long-term geochemical processes considering CCUS.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2469

Bioweathering of chrysotile asbestos Cd isotope fractionation during KIRSTIN E. WASHINGTON* 1, JANE K. WILLENBRING1 sorption to Mn oxide at low and high AND BRENDA CASPER2 ionic strength 1 University of Pennsylvania, Department of Earth and 1 1 LAURA E. WASYLENKI AND JARED W. SWIHART Environmental Sciences, Philadelphia, PA 19104, USA 2University of Pennsylvania, Department of Biology, 1Department of Geological Sciences, Indiana University, Philadelphia, PA 19104, USA Bloomington, Indiana USA 47405 ([email protected]) *[email protected] Two potential applications of Cd isotopes motivate this study: The serpentine mineral, chrysotile, is the most common First, some diatoms have evolved to use Cd instead of Zn asbestiform mineral at asbestos-contaminated sites. Similar in in their carbonic anhydrase enzyme [1]. Because these diatoms mechanism to other asbestos minerals, its toxicity is related to strongly fractionate Cd isotopes [2], marine sediments may the presence of iron, which induces oxidative stress, and the preserve isotopic records of Cd utilization and diatom fiber’s shape, which can lead to piercing of lung alveoli and productivity in the past. A recent study [3] indicated that induces inflammation. ferromanganese crusts in particular might preserve a Previous research has developed the idea that fungi straightforward record of global deepwater Cd isotopes. Fusarium oxysporum endemic to serpentine substrates ( and Second, for freshwater or groundwater contaminated with Verticillium leptobactrum ) can remove atoms of key elements Cd, sorption to Mn oxyhydroxide particles can be the from asbestos particles, rendering them less toxic[1]. In this dominant process retarding mobility of this toxic heavy metal study, we investigate natural mechanisms of removal of (except in sulfide-rich conditions). If sorption drives a impurity elements (Fe) and structural cations (Mg, Si) from distinctive isotope effect, then determining the extent to which the chrysotile asbestos fibers. We ran greenhouse experiments sorption reactions are attenuating flow of Cd may be possible Brassica using heavy metal accumulating plant species, by tracking Cd isotope signatures in soils or water. juncea, Helianthus annuus Thlaspi caerulescens , and . We also To lay groundwork for these potential applications and to Sorghastrum planted the native serpentine grassland species, investigate fractionation mechanisms for Cd, we conducted nutans , whose roots form mutualist relationships with sorption experiments using particles of the Mn oxyhydroxide arbuscular mycorrhizal fungi (AMF). We also evaluated the birnessite, both in pure water and in synthetic seawater. use of fungal exudates to remove iron from asbestiform Suspensions of synthetic birnessite particles were doped with chrysotile through cultured fungal experiments for different Cd and allowed to react for 24 hours (pH adjusted to 8-8.5). Fusarium species of . Dissolved and sorbed Cd pools were separated by filtration, We analyzed the iron content of plant tissue, fungal tissue, purified by ion exchange chromatography, and analyzed by and iron in solution in fungal growth media and organic acid MC-ICP-MS. solutions over time via ICP-OES. We imaged the chrysotile At low ionic strength we observed a constant offset of fibers and fungi mycelium using an ESEM to determine the +0.15‰ (!114/112Cd) between dissolved and sorbed Cd (sorbed change in mineral structure and aspect ratio over time, and we is lighter), regardless of proportion sorbed. This is consistent assessed the change in mineral composition of untreated and with reversible sorption driving an equilibrium isotope effect. treated asbestos samples via XRD. Preliminary data At high ionic strength, the magnitude of fractionation demonstrate that Brassica juncea was able to remove an increased with the proportion of Cd adsorbed, suggesting a average of 300ppm Fe per gram of plant tissue from the kinetic or Rayleigh effect. The difference between low and surface of chrysotile asbestos, and there was no difference in high ionic strength results is likely driven by solution plant biomass when compared to plants grown with the speciation; chloro- complexes dominate Cd speciation in addition of fertilizer containing iron. Preliminary results from synthetic seawater. We hypothesize that the difference in the fungi treatments show that fungi take up iron but do not bonding environment between Cd2+ and an inner-sphere liberate the iron into the broth solution. sorbed complex drives the equilibrium effect at low ionic strength, while fractionation in solution between various [1] Daghino, S. et al. 2006. ES&T 40: 5793-5798. chloro- complexes becomes important at high ionic strength.

[1] Price & Morel (1990) Nature 344, 658. [2] Lacan et al. (2006) Geochim. Cosmochim. Acta. 70, 5104. [3] Horner et al. (2010) G3, doi:10.1029/2009GC002987.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2470 Goldschmidt2013 Conference Abstracts

Hayabusa-2 – sample return from Geochemical discrimination of a near-Earth C-type asteroid tsunami sediments in Tohoku and (2014-2020): Current status Shizuoka area, Japan S. WATANABE*, M. ABE, M. ARAKAWA, M. FUJIMOTO, T. WATANABE1*, N. TSUCHIYA1, C. INOUE1, A. M. ISHIGURO, K. KITAZATO, N. KOBAYASHI, N. NAMIKI, KITAMURA2, T. KOMAI3, S. YAMASAKI1, R. YAMADA1, N. T. OKADA, S. SUGITA, S. TACHIBANA, S. TANAKA, M. HIRANO1, A. OKAMOTO1, F.W. NARA1 AND TOHOKU AND YOSHIKAWA, H. KUNINAKA AND HAYABUSA-2 PROJECT TSUNAMI SEDIMENT RESEARCH GROUP TEAM 1 Graduate School of Environmrntal Studues, Tohoku *Nagoya U., Nagoya 464-8601. [email protected] University, Sendai 980-8579, Japan 2 Faculty of Science, Shizuoka University, Shizuoka 422- Hayabusa-2 is an asteroid exploration mission to return 8059, Japan 3 surface samples of a near-Earth C-type asteroid 1999 JU3. National Institute of Advanced Industrial Science and Because asteroids are the evolved remnants of planetesimals Technology, Tsukuba 305-8564, Japan that were the building blocks of planets, detailed observation by a spacecraft and analyses of return samples will provide Tsunami sediments from the stricken area direct evidence of planet formation and dynamical evolution Geochemical studies of modern and past-tsunami of the solar system. Moreover, C-type asteroids are expected sediments were performed to detect a tsunami invasion proxy. to preserve the most pristine materials in the solar system, an In this study, the modern tsunami sediments from the Pacific interacted mixture of minerals, ice, and organic matter. Space coast of Tohoku area, Japan (March.11th, 2011), have been missions are the only way to obtain such pristine materials analyzed by EDXRF and ICP-MS. In addition, past-tsunami with geologic context and without terrestrial contamination. In sediments were also taken from the coastal area of Japan order to understand the dynamical and chemical evolution of (Jogan, ca. 1100 BP; Yayoi, ca. 2000 BP; Sizuoka, ca. 3000

the solar system by investigating and sampling 1999 JU3, BP) in order to establish a novel method for the geochemical Hayabusa-2 sets the following scientific objectives: (1) discrimination of invisible tsunami layers, such as mud and Thermal evolution from planetesimal to near-Earth asteroid, thin sand layers. (2) Destruction and accumulation of rubble pile body, (3) Diversification of organics through interactions with minerals Na/Ti atomic ratios of tsunami sediment and water on planetesimal, and (4) Material circulation in the Na/Ti and Si/Al atomic ratios in the tsunami sediments early solar system. The basic design of the spacecraft is the varied from 2.7 to 22.4 and from 1.7 to 13.6, respectively (Fig. same as in the original Hayabusa, but many improvements 1). The Na/Ti ratios markedly increased up to ca. 7-22 in the will be made and new technology will be adopted. The on- tsunami layers from the northeast (Tohoku area) and middle board instruments necessary for the fulfillment of the Japan (Shizuoka prefecture). Our results show that the Na/Ti scientific objectives are a laser altimeter (LIDAR), a multi- values are useful indicator of past-tsunami sediment layers. band camera (ONC-T), a near-infrared spectrometer (NIRS3), a thermal infrared imager (TIR) and a wide-angle camera Jogan tsunami sediment layer (ca. 1100 BP)
(ONC-W). A small impactor (SCI) will also be aboard for an asteroid-scale impact experiment, which will make a crater of Top 10 cm "" "" "" "" "" "" "" "" "" "" ""

several meters in diameter. The sampler, of which concept "" and design are also the same as the original Hayabusa, has ""
"" "" Na / Ti 20
three projectiles for impact sampling and the sample container 20

Si / Al "" has three separate rooms inside for sampling at three different "" "" ""
locations, one of which could be ejecta from the artificial 10
10 "" impact to sample sub-surface materials. "" "" "" 0
"" "" "" "" "" "" "" "" "" "" "" Hayabusa-2 will be launched in late 2014, arrive on 1999 0
Al (atomic ratio)
Si / Na / Ti (atomic ratio)
Ti Na / 0
40
80
120
160
200
JU3 in mid-2018, and fully investigate and sample the asteroid Core depth (cm)
during its 18-month stay. The spacecraft will return to Earth with samples in December 2020. Preliminary integration tests Figure 1: Na/Ti and Si/Al atomic ratios of tsunami sediments of the spacecraft are now being made, and the current mission (Jogan, ca. 1100 BP) from Sendai plain in Tohoku area, Japan. status will be presented at the meeting.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2471

Corals at volcanic island of Satsuma Applications of neutron beam iwo-jima: Implication for a new analysis to study the origins of proxy of hydrothermal events and carboneceous matter in terrestrial biological adaptation and planetary rocks: A new approach T. WATANABE1, K. KAMIMURA1, A.YAMAZAKI1&2* , Y. WATANABE1*, Y. FURUKAWA2, T. KAKEGAWA2 AND K. OMORI1, F. LE GUERN3 AND S. KIYOKAWA4 H. OHMOTO3 1Grad. Sch. of Science, Hokkaido Univ., Sapporo, 060-0810, 1J-PARC, Ibaraki 319-1195, Japan (*correspondence: JAPAN (*correspondence: [email protected], [email protected]) [email protected],[email protected] 2Tohoku University, Sendai, Miyagi 980-8578, Japan p, [email protected]) ([email protected], [email protected]) 2AORI, University of Tokyo, Kashiwa, Chiba, 277-0882, 3PSARC and Penn State University, College Park, PA 16802, JAPAN([email protected]) USA ([email protected]) 3CNRS, LSCE, Gif sur Yvette, 91190, France (Deceased) 4Grad. Sch. of Science, Kyushu Univ. Fukuoka 812-8581 Some of the most fundamental and and important JAPAN ([email protected]) questions in the fields of Earth Sciences, Biology and Astrobiology are when, where and how life originated and Coral cores from massive corals could record marine different species evolved from the common ancestor during environmental and ecological changes in their annual bands the 4.5 billion years history of the Earth. For exmple, we do with monthly temporal resolution in the present and/or the not know whether carbonaceous matter in a particular Archean past. We discovered large massive Porites corals living at sedimentary rock represents a product of inorganic processes active volcanic island of Satsuma Io-Jima, located 50 km (e.g., Fisher Trophsch reactions) or a remnants of organisms. south from Kyushu area, southern part of Japan. Satsuma Io- Similarly, the origins of carbonacerous matter in meteorites, Jima provides a unique opportunity to observe marine Mars, and other planetary rocks have been debated. organism living under extreme environments of volcanic gases The origins of carbonaceous matter in terrestrial and emission and different types of hydrothermal activities from planetary materials have been investigated primarily from its sea flower. We collected eleven coral cores from four different chemical, isotopic, and physical characteristics, such as the conditions around the island to test if corals could record H/C/N/P ratios, H, C, N, and S isotope ratios, crystal structure, volcanic and hydrothermal activities and how corals could and crystalinity. Here we introduce a new method, an survive in extreme environments such as very low pH application of neutron beam analysis, to determine the condition with CO2 gasses emission. Coral extension rate for chemical composition and crystal structure of solid the site near hydrothermal vent was significantly small (1- carbonacerous matter. Compared to the other techniques using 2mm/year) relative to that for general condition of Porites x-ray, such as XRD, an advantage of neturon beam analysis is corals (ca. 10-20 mm/year), suggesting that coral growth was that it will identify the positions of light elements, particularly influenced by hydrothermal activity. We will demonstrate our hydrogen, in the structure. preliminary results of geochemical approaches of "18O, We will present the results of our preliminary "1
C, Sr/Ca, Mg/Ca, Ba/Ca, and F/Ca in coral skeletons and investigations using neutron scatter analysis, XRD, and in surrounding seawater and discuss the possibility for Raman spectroscopy on simple organic compounds (e.g., reconstructing the past hydrothermal events and relationship glycin steroid), micro-organism (e.g., cyanobacteria), and between marine ecosystem and extreme environments at kerogens of various geologic age. volcanic activity as the analogues for coral adaptation to future ocean acidification.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2472 Goldschmidt2013 Conference Abstracts

Influence of kinetics on the oxygen First melt inclusion study of the isotope composition of calcite Sudbury Igneous Complex (Ontario, J. WATKINS1*, L.C. NIELSEN2, F.J. RYERSON3 Canada): Evidence for two-liquid AND D.J. DEPAOLO4, immiscibility and constraints on trace 1University of Oregon, Eugene, OR 97403, USA element distribution (*correspondence: [email protected]) 1 1 2Stanford University, Palo Alto, CA 94305, USA KATHLEEN WATTS *, JACOB J. HANLEY , DANIEL 2 3 3Lawrence Livermore National Laboratory, Livermore, CA KONTAK AND DOREEN AMES 94550, USA 1 4 Saint Mary’s University, Halifax, NS, Canada Lawrence Berkeley National Laboratory, Berkeley, CA (*correspondence: [email protected]) 94720, USA 2MERC, Laurentian University, Sudbury, ON, Canada 3 Geological Survey of Canada, Ottawa, ON, Canada Paleotemperature reconstructions rely on knowledge of the

equilibrium fractionation of oxygen isotopes between aqueous solution and calcium carbonate. Although oxygen isotope The 1.85 Ga Sudbury Igneous Complex (SIC), Ontario, separation is expected on theoretical grounds, the temperature- Canada, is an intrusive complex representing a crystallized dependence remains uncertain because other factors, such as melt sheet formed during a bolide impact. The SIC has been extensively studied due to its rich endowment in magmatic slow exchange of isotopes between dissolved CO2-species and water, can obscure the temperature signal. This is problematic sulfide ores (Ni-Cu-PGEs). In this study, primary melt for crystal growth experiments on laboratory timescales and inclusions hosted in cumulus apatite within three mafic units for interpreting the oxygen isotope composition of crystals of the SIC (gabbro, norite and sublayer quartz diorite) are used formed in natural settings. to decipher the physical and chemical characteristics of the We present results from experiments in which inorganic evolving melt sheet as it crystallized. calcite is precipitated in the presence of 0.25 %M dissolved The compositions of coeval melt inclusions show 2 distict

bovine carbonic anhydrase (CA). The presence of dissolved types: (1) SiO2-rich, ranging from tonalitic to granodioritic in CA accelerates oxygen isotope equilibration between the composition (60-70 wt% SiO , up to 11 wt% FeO); and (2) Fe- ( 2( 2 dissolved carbon species CO2, H2CO3, HCO3 , CO3 and rich with syenogabbroic to essexitic to alkali gabbroic water, thereby eliminating this source of isotopic compositions (27-49 wt% SiO2, 16-44 wt% FeO). The liquids disequilibrium during calcite growth. The experimental results are interpreted to represent the products of immiscibility (c.f. allow us to isolate kinetic oxygen isotope effects occurring at Skaergaard Intrusion [1]). the calcite-water interface during mineral growth. D Fe-rich melt/Si-rich melt values range between ~0.7 and ~2 with The oxygen isotope composition of precipitated calcite is - 2- the exception of V and Co that partition more strongly into the lighter than dissolved HCO3 yet heavier than CO3 at pH = 8.3. 18O uptake into calcite varies with precipitation rate, but Fe-rich melt (D > 4). Microthermometry shows that complete the observed rate-dependence is lower than in previous studies melting of the inclusion contents occurs at ~1100°C, with where calcite is not precipitated in the presence of dissolved homogenization (i.e., minimum trapping T; by bubble CA. These non-equilibrium effects can be explained in terms contraction) between ~1230 and 1300°C, confiming that of isotopologue-specific reaction rate coefficients. We present apatite is an early liquidus phase in melt and trapped melt over a framework of ion-by-ion growth of calcite that reconciles a range of temperatures. Preliminary melt inclusion analyses our new measurements with measurements of natural cave suggest that the earliest melt phase of the SIC, as represented calcites that are the best candidate for having precipitated by sublayer quartz diorite, was enriched in Ni and Cu, up to an under near- equilibrium conditions. Our findings suggest that order of magnitude higher than those liquids trapped in the isotopic equilibrium between calcite and water is unlikely to units stratigraphically higher in the SIC, and may reflect loss have been established in laboratory experiments or in many of these metals to early sulfide liquids. natural settings. The use of CA in carbonate precipitation The results of this study may lead to the development of experiments offers new opportunities to refine oxygen isotope- parameters that enhance exploration success in mafic- based geothermometers and to interrogate environmental ultramafic systems where post-magmatic processes have variables other than temperature that influence calcite growth severely limited the application of bulk rock chemistry in rates. understanding their petrogenesis.

[1] Jakobsen et al. (2005) Geology 33, 885-888.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2473

Effect of magma oxidation state on Amino acid binding on oxide iron isotope composition of surfaces: Results from CTR and magmatic-hydrothermal minerals surface x-ray anomalous scattering CHRISTINE WAWRYK* AND JOHN D. FODEN GLENN WAYCHUNAS1, JOANNE STUBBS2 AND PETER ENG2 Centre for Tectonics, Research and Exploration, University of Adelaide, South Australia, 5005 1Lawrence Berkeley National Laboratory, Earth Sciences (*correspondence: [email protected]) Division, Berkeley, CA, USA 2University of Chicago, Consortium for Advanced Radiation Do ore minerals precipitated from magmatic-hydrothermal Sources, Argonne, IL, USA solutions reflect the isotopic composition of the parent magma? We present new stable iron isotope compositions of The interaction and binding of organic species and amino sulfides from two deposits associated with fractionated, acids with mineral surfaces is a large frontier in geochemistry. reduced magmas. The Renison tin deposit is associated with As opposed to inorganic sorbates, which interact with a magmatic fluids exsolved from an S-type magma [1]. The surface by forming covalent and hydrogen bonds, organic Hillside deposit is an IOCG skarn associated with an A-type structures may have partial or dominant hydrophobic granite of the Hiltaba Suite [2]. Figure 1 compares isotopic interactions and reduced interaction with waters, multiple composition of host intrusions, pyrite and chalcopyrite from charges on a single molecule such as a zwitterion, and very Renison with published data from Grasberg [3] and Xinqiao complex multi-site interactions with surface functional groups. [4]. These considerations have limited the utility of many studies in the past, with the vast majority involving measurement of uptake concentrations without information on the actual binding geometry or mechanisms. We are developing a program to couple sum-frequency vibrational spectroscopy (SFVS), surface x-ray scattering methods, and computer simulations to characterize organic species topologic interactions with well-known mineral surfaces. Initial investigations examined ethanol as a single monolayer, and as a bulk liquid, on the corundum R-plane (1-102) surface using SFVS. Subsequent studies examining selenomethionine and other heavy atom-substituted amino acids are in progress. This approach enables x-ray surface scattering and anomalous scattering measurements to be correlated with SFVS vibrational information. The complexities and advantages of Figure 1. Comparison of "57Fe composition of host this approach will be described, as well as most recent results. intrusions, pyrite and chalcopyrite.

Our results demonstrate that sulfides associated with the reduced Hillside and Renison Granites have, on average, heavier iron isotopic compositions than ore minerals associated with the oxidised GIC, and the Jitou Stock hosting Xinqiao. Our modelling of magma/fluid evolution considers variables such as fO2, pressure and temperature.

[1] Patterson et al. (1981) Econ Geol 76 393-438. [2] Conor et al (2010) Hydrothermal IOCG and Related Deposits 3 147- 170 PCG Publ. [3] Graham et al. (2004) Chem Geol 207 147- 169. [4] Wang et al. (2011) Ore Geol Rev 43 194-202. [5] Teng et al. (2013) Geochim Cosmochim Acta 107 12-26.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2474 Goldschmidt2013 Conference Abstracts

Probing quartz for P-T-D paths Micro-scale complexity in iron-sulfide LAURA E. WEBB1, PATRICK G. DYESS1, KYLE T. phases in Precambrian sedimentary ASHLEY2, FRANK S. SPEAR3 AND JAY B. THOMAS3 rocks determined by coupled 1University of Vermont, Department of Geology, Burlington, spectroscopic, isotopic, and magnetic VT, USA, [email protected], [email protected] 2 Department of Geosciences, Virginia Tech, Blacksburg, VA, USA, techniques [email protected] 1 2 3 SAMUEL M. WEBB *, JENA E. JOHNSON , Earth and Environmental Sciences, Renssaelaer Polytechnic 2 2 SARAH P. SLOTZNICK , JOSEPH L. KIRSCHVINK Institute, Troy, NY, USA, [email protected], [email protected] AND WOODWARD W. FISCHER2

1 TitaniQ (Ti-in-quartz) thermobarometery of chlorite– Stanford Synchrotron Radiation Lightsource, Menlo Park, CA staurolite grade metapelites reveals that quartz grains in 94025, USA (*correspondence: different fabric domains may record distinct stages of the P-T- [email protected]) 2 D path and, in some cases, preserve detrital [Ti] signatures. California Insitute of Technology, Pasadena, CA 91125, USA Our findings are based on integrated microstructural and petrologic analyses, cathodoluminscence (CL) imaging, and The record of sedimentary pyrite forms the foundation for secondary ion mass spectrometry (SIMS) of samples with most isotope records working to define the coupled evolution known tectonic histories collected along an E–W transect and behavior of the ancient iron and sulfur cycles. In order to across central Vermont, spanning rocks of the Rowe–Hawley assess the strengths and limitations of records derived from Belt (RHB) and the Connecticut Valley–Gaspe Trough pyrite-rich rocks (e.g. iron speciation, sulfur isotope ratios), (CVG). Rocks of the RHB record crenulation cleavage we need to understand more about the processes that form and development during both the Taconic and Acadian orogenies; alter sedimentary pyrite. CVG rocks record similar processes during the Acadian From samples of the Archean/early Proterozoic Transvaal orogeny only. CL and SIMS analyses were conducted on and middle Proterozoic Belt Supergroups, petrography reveals quartz in different microstructural contexts such as in fold that what might operationally be called sedimentary pyrite has hinges, quartz-feldspar cleavage domains, inclusion suites complex textures that hint at a rich process history of sulfur defining internal foliations in garnet, and pressure shadows. mineralization. A common limitation of virtually all proxy Both suites of metapelites lack evidence for significant measurements employed to date is that they operate on ‘bulk’ dynamic recrystallization of quartz; quartz grains samples, typically gram-sized or larger pieces. As such, they predominately display polygonal textures. The dominant CL lose the ability to relate geochemistry to petrography at the zoning pattern of quartz is darker rounded–anhedral cores and scale of mineral grains. Many of the sedimentary pyrites in the brighter polygonal rims, indicating an increase in [Ti] from Transvaal Supergroup exhibit complex redox and electronic core to rim. In some cases grains record bright cores with dark structures of S and Fe, with crystals of pyrite, pyrrhotite, and rims (RHB), or dark cores, bright mantles, and dark rims sulfate-bearing minerals throughout. (CVG). RHB chlorite–garnet grade metapelites yield [Ti] from Parallel application of multiple techniques on the same 0.4–157 ppm; a small fraction of analyses yield [Ti] greater samples across micron bases spatial scales, provide an than that predicted for peak metamorphic conditions. Analyses opportunity to diagnose issues resulting from post- of garnet–staurolite grade CVG metapelites yielded [Ti] of depositional alteration of sedimentary rocks. We have 2.2–9.8 ppm. In both suites, dark cores with low [Ti] are integrated light and electron microscopy for petrography, interpreted as quartz growth during burial metamorphism and electron microprobe and synchrotron XRF for elemental cleavage development via strain-induced solution transfer. composition, synchrotron X-ray spectroscopy for redox and Brighter mantles and rims with increasing [Ti] relative to chemical state, SQUID microscopy for remnant magnetism, cores result from quartz-producing metamorphic reactions and and secondary ion mass spectrometry (SIMS) for isotopic continued solution transfer to low strain and quartz-feldspar composition. The coupling of these tools allows in essence domains. [Ti]>50 ppm in RHB rocks are interpreted to be “images” of the proxy data at the micrometer scale, giving a inherited detrital signatures and thus likely provide wide array of textural and mineralogical information designed information on sedimentary provenance of the protoliths. to inform and untangle the complicated histories of these early These studies highlight the importance that both structural and Precambrian rocks. metamorphic processes play in the cycling of quartz in metapelites and its ability to record P-T-D paths.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2475

Large 34S depletions of reduced The cycling and transport of glacially sedimentary sulfides at low sulfate derived iron in Arctic fjord sediments concentrations in an iron-rich lake L.M. WEHRMANN1*, M.J. FORMOLO2, J.D. OWENS1, T. dominated by anaerobic methane G. FERDELMAN3, R. RAISWELL4 AND T.W. LYONS1 oxidation 1University of California, Riverside, Riverside, CA, USA, [email protected], [email protected],

WEBER H.S.*, THAMDRUP B. AND HABICHT K.S. [email protected] (* presenting author) 2 Nordic Center for Earth Evolution and Institute of Biology, The University of Tulsa, Tulsa, OK, USA, michael- [email protected] University of Southern Denmark, Campusvej 55, 5230, 3 Odense M, Denmark (*correspondence: Max Planck Institute for Marine Microbiology, Bremen, Germany, [email protected] [email protected]) 4 University of Leeds, Leeds, UK, [email protected] The sediment of Lake Ørn (Denmark) is characterized by a high reactive iron content and a strong methane consumption Iron is an essential nutrient for primary production and is in the deep sulfate-containing zone reaching ~15 cm depth. strongly connected to glacial-interglacial variations in Radiotracer studies (14C-methane and 35S-sulfate) confirmed atmospheric CO2 concentrations. Glacial runoff rapidly anaerobic oxidation of methane (AOM) and microbial sulfate delivers large volumes of potentially bioavailable Fe, reduction (SR) and demonstrated the highest AOM rates (up to produced by mechanical and microbially enhanced chemical 40 nmol cm-3 day-1) at 10-15 cm depth with very low sulfate weathering in glacial environments, to high latitude oceans. concentrations (5-10 µmol L-1). We further used stable sulfur Little is known about the fate of this Fe pool in adjacent isotope analysis and incubation experiments to investigate the coastal marine waters, particularly fjord systems. We interactions of iron, sulfur and methane with particular focus investigated the concentration and speciation of Fe in the on a hypothetical cryptic sulfur cycle. Isotope analyses sediments of three Western Svalbard fjords with the aim of revealed substantial 34S depletion in reduced sulfur species quantifying and understanding the biogeochemical processes with 34S values of down to -15‰ for acid volatile sulfides of the sedimentary Fe cycle. Results of porewater and solid- 0 phase analyses show that the input of glacially derived Fe (H2S and FeS) and -25‰ for chromium reducible sulfides (S plays an important role in the biogeochemical processes in and FeS2) accumulating in the AOM zone. Anoxic slurry incubations demonstrated "34S values of up to 40‰ in sulfate fjord sediments by controlling sulfur and manganese cycling in the incubations with methane and S0 respectively, indicating and by providing a large Fe-oxide pool for dissimilatory iron that large sulfur isotope fractionations can be established by a reducers (DIR). Extreme sedimentation rates in the fjords combination of sulfate reduction, sulfide oxidation, AOM and result in elevated Fe accumulation but dilution of the organic microbial sulfur disproportionation. RNA stable isotope carbon pool. From this combination, the sediments show a probing was applied to identify key players of the cryptic strong signature of DIR, leading to high dissolved Fe sulfur cycle. concentrations of up to 800 µM in the porewaters of Kongsfjorden and Van Keulenfjorden and correspondingly enhanced benthic Fe flux from the sediment to the water column. Our data point to extensive benthic Fe cycling in Svalbard fjord sediments likely promoted by bioturbation and physical disturbance via iceberg calving. Thus, recycling of iron in fjord sediments may facilitate the transport of this important micronutrient across the fjords while maintaining its bioavailability for fertilization of primary productivity on the adjacent continental shelf. This work complements recent studies on the bioavailability and concentration of Fe in glacial runoff and contributes to the emerging picture that glacially derived Fe may constitute an important component of the global Fe cycle, particularly in high-latitude ocean regions.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2476 Goldschmidt2013 Conference Abstracts

Using radium isotopes to determine Low-T hydrothermal fluid evolution the residence time of circulated C. G. WEINZIERL1*, W. BACH2, F. BÖHM3 seawater in coastal sediments M. REGELOUS AND K.M. HAASE1 1 1 1 1 GeoZentrum Nordbayern, Univ. Erlangen-Nuernberg, WEINSTEIN Y. , SHALEM Y. , BRINBERG B. 1 Schlossgarten 5, 91054 Erlangen, Germany AND NOIMEIR Y. (*correspondence: [email protected]) 1 Bar-Ilan University, Ramat-Gan 52900, Israel 2Geoscience Department, Bremen Univ., Klagenfurter Str., (*correspondence: [email protected]) 28359 Bremen, Germany 3GEOMAR Helmholtz Centre for Ocean Research Kiel, The circulation of seawater in seafloor sediments and the Wischhofstr. 1-3, 24148 Kiel, Germany resultant fluxes of water to the water column are highly important to oceanic mass balances of certain elements and to The chemical and isotopic composition of calcium coastal water quality. The residence time of this water in the carbonate veins precipitated within the oceanic crust can be sediments is critical to the kinetics, therefore the effectiveness used to infer the composition of their parent fluid [1], and of water-rock interaction, which further affects the delivery of trends of fluid compositions with temperature [2] can be chemicals from the sub-seafloor to the ocean. extrapolated to estimate ancient ocean water compositions [3, We used radium isotopes to decipher about the residence 4]. Previous studies focused on carbonates from drillcores in time of circulated seawater in coastal sediments. Seawater is ancient oceanic crust, but ophiolites could be used to extend radium-poor, with the activity of 226Ra (half time of 1605 yrs) the record of ocean water chemistry further back in time. We on the order 0.1 dpm/L, and those of the short-lived isotopes, evaluated the potential of ophiolites as paleoseawater archives 224Ra and 223Ra (half lives of days), being close to zero. On the by analysing carbonates from the Cretaceous Troodos other hand, activities in pore water of both short and the long- Ophiolite of Cyprus. lived isotopes may be 2-3 orders of magnitude higher. Another Variations of fluid Sr/Ca, Mg/Ca, 87Sr/86Sr and 44Ca/40Ca important consideration is that while the pore water activities with temperature ("18O) in the volcanic section of the Troodos of the long-lived 226Ra are pretty much controlled by Ophiolite display similar trends to data for fluids [2] and desorption, those of the short lived isotopes are mainly carbonates [3, 4] from drilled oceanic crust, indicating that controlled by recoil during the disintegration of their thorium similar processes acted upon the fluids. In accordance with radioactive parents. Gonnea et al. (2008) have shown that experimental results [5] we found that the formation of pore water attains secular equilibrium for 226Ra within a few saponite and palagonite, and the subsequent precipitation of hours, may be less. On the other hand, since 224Ra in pore anhydrite, are responsible for modifying the composition of water is enriched by recoil due to the disintegration of seawater as it percolates downwards through the oceanic crust. sediments’ 228Th, the activity of this nuclide may be built-up Our data and thermodynamic calculations indicate that during a period of up to several weeks, which could be more anhydrite may form at much lower temperatures (! < 70°C) relevant to the proces of seawater circulation (hours to years). than previously thought [6], if seawater interacts with basalt. We pumped pore water using mini piezometers from Our results allow not only to identify fluid evolution depths of 0.5-2 m in the granular sediments (quartz sands) of pathways affected by mixing of seawater with a more evolved Dor Bay (eastern Mediterranean, northern Israel). Water fluid (e.g. Juan de Fuca), but also to show that ophiolites can salinities were between 30-39 (eastern Mediterranean water be used to determine past seawater compositions, and to study salinity is ~40, psu scale). 226Ra activities were mostly 2-2.5 the chemical evolution of fluids in greater detail than is dpm/l, though in a few shallow cases (0.5 m), activites possible using samples drilled from oceanic crust, where dropped to <1 dpm/l. Experiments showed similar 226Ra recovery of interstitial carbonates is less complete. ctivities of 2-3 dpm/l, which suggests that the residence times of pore water are longer than a few hours. Activities of 224Ra [1] Coggon et al. (2004) EPSL 219, 111 - 128. [2] Elderfield varied between 1.5-6.5 dpm/l, with the deeper water (1.5-2 m) et al. (1999) EPSL 172, 151-165. [3] Coggon et al. (2010) significantly more enriched than the shallow ones (0.5-1 m). Science 327, 1114-1117. [4] Rausch et al. (2013) EPSL 362, In chromatography experiments with the same sediments and 215-224. [5] Seyfried & Mottl (1982) Geochim. Cosmochim. coastal seawater, 224Ra increased from <0.5 to 4 dpm/l at Acta 46, 985-1002. [6] Bischoff & Seyfried (1975) Amer. J. residence times of 1 and 24 hrs, respectively. Assuming Sci. 278, 838-860. uniform sediment characteristics. this suggests that the average age of pore water at 1-2 m depth is about 0.5-2 days.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2477

“Tuning the Torch” of the Nu Plasma Matrix-independent calibration of II-ES MC-ICP-MS LA-ICP-MS using D. WEIS1*, K. GORDON1, L. XING1, A. BURROWS2, femtosecond-UV-lasers? 2 2 R. COHEN AND P. FREEDMAN 1 1 1 2 U. WEIS *, K.P. JOCHUM , B. STOLL , D. JACOB , 1Pacific Centre for Isotopic and Geochemical Research, R. MERTZ-KRAUS2 AND M.O. ANDREAE1 Department of Earth, Ocean and Atmospheric Sciences, 1 Max Planck Institute for Chemistry, Mainz, Germany University of British Columbia, 2207 Main Mall, (*correspondence: [email protected]) Vancouver BC, V6T 1Z4, Canada. *[email protected] 2 2 University of Mainz, Germany Nu Instruments Ltd, 74 Clywedog Road South, ,Wrexham Industrial Estate, ,Wrexham LL13 9XS, United Kingdom The major limitations regarding accuracy and precision of LA-ICP-MS trace element analysis are elemental fractionation Since the development in the early 1990s of the first multi- [1] and mass-load-dependent matrix effects [2]. Reducing the collector inductively coupled plasma mass spectrometer, there pulse width of the laser from the ns to the fs range leads to an has been an unprecedented broadening of isotopic analysis improvement of the analytical results, in particular for in-situ applications in geochemistry, mostly because the ICP source isotope ratio measurements [3], where matrix related mass effectively ionizes virtually all elements in the periodic table. fractionation is considerably reduced. To test matrix-related The Nu Plasma II-ES is Nu Instruments Ltd.’s latest effects in trace element analysis, we determined the generation plasma source multi-collector mass spectrometer. fractionation factors (FF) and element/Ca ratios in reference The NP II at UBC is equipped with a newly designed ES materials with different matrices (silicate, basalt, phosphate, interface system that increases the overall sensitivity of the carbonate) by a Ti-sapphire based fs-UV-LA-ICP-MS. instrument. Additionally, the instrument is equipped with an Measurements were performed with different spot sizes (10 – enhanced detector system that includes large dynamic range 55 µm), pulse repetition rates (PRR) (10 – 250 Hz) using spot 55 volt Faraday amplifiers coupled to 16 Faraday detectors and line scan mode. For comparison, similar experiments were plus 5 full-size discrete dynode ion counters. Sensitivity tests made using 213 nm and 193 nm Nd:YAG lasers and a 193 nm across the mass range, from Li to U, reveal a significant ArF excimer laser. increase compared to the previous generation interface. We Our measurements demonstrate that in each case the fs tested the instrument for stability of mass bias and accuracy of data are more reproducible and less matrix-dependent with isotopic ratios while measuring oxide production, interface respect to FF and mass-load induced matrix effects than the pressure, and other key parameters. results obtained using the other lasers. The FF are independent This work demonstrates that the enhanced sensitivity can of the measuring conditions and of the matrix within about 0.3 be achieved with no compromise in either mass bias stability - 1 % and 0.5 - 3 % for line scan and spot analysis, or isotope ratio accuracy. Small sample concentrations of Nd, respectively. The line scan mode yields unity FF, whereas in Hf and Pb are now analyzed to precisions previously the spot analysis mode small, but significantly lower values attainable only with great analytical effort or by pooling for the volatile elements Zn (0.88) and Pb (0.93) were samples. Larger samples show much improved external observed. The ratios of the lithophile elements Sr, Ba, Rb to reproducibility that previously required longer analysis times. Ca are identical for all spot sizes, PRR and materials within The improved ion interface and detector systems on the NP II- about 5%, for both line scan and spot analyses. An extreme ES increase the overall productivity and analytical capability dependency of the element ratio with spot size (up to 50%) of multi-collector ICP-MS, which is especially advantageous was found for Pb/Ca and Zn/Ca using spot analysis; however, it is similar for all matrices. This is in contrast to in a multi-disciplinary laboratory. measurements done with the 213 nm Nd:YAG laser, where These improvements open up new avenues in geochemical high spot sizes may lead to different element/Ca ratios research with analyses of samples down to sub-ppm levels or compared to low spot sizes. Consequently, the use of fs-UV with transient signals. They will allow further understanding lasers improves not only high-precision isotope ratio of the timing and processes, and fingerprinting of sources, in measurements but also trace element analysis. Calibration can Earth, planetary, biological and medical science. be performed reliably for quite different matrices with certified reference materials, e.g. those from NIST [4].

[1] Fryer et al. (1995) Can. Min. 33, 303-312. [2] Kroslakova and Günther (2007) JAAS 22, 51-62. [3] Horn et al. (2006) GCA 70, 3677-3688. [4] Jochum et al. (2011) GGR 35, 397- 429.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2478 Goldschmidt2013 Conference Abstracts

Bacterial mineral-metaloid redox Diamond-forming fluids: transformations in anearobic The trace-element perspective environments Y. WEISS1,3*, W. L. GRIFFIN2 AND O. NAVON1 CHRISTOPHER WEISENER1*, RACHEL FRANZBLAU1 AND 1The Institute of Earth Sciences, The Hebrew University of NADINE LOICK1,2 Jerusalem, Edmund J. Safra Campus, Israel 2 1 CCFS and GEMOC, Dept. of Earth andPlanetary Sciences, 1Great Lakes Environmental Institute for Research, University of Macquarie University, NSW, Australia Windsor, Windsor, Canada, [email protected]* 3Lamont-Doherty Earth Observatory, Columbia University, 61 2Rothamsted Research Institute, NorthWyke, UK Rt. 9W, Palisades, NY 10964-1000, USA

(*correspondence: [email protected]) Jarosite minerals are of environmental importance as trace

metal scavengers and are involved in metal cycling. A Diamond-forming high-density fluids (HDFs) of different number of metal species can be incorporated into the jarosite major-element composition share similar incompatible- structure, including selenium (Se). Se is a trace nutrient, but is element characteristics, regardless of their host diamond toxic in relatively low doses to humans, microbes, and other provenance. All have fractionated REE patterns and variable, fauna[1]. Se is present in aqueous systems in its two oxyanion mostly negative, anomalies (PM normalized) in K, Rb, Cs, Ti, forms; selenate and selenite (SeO 2- & SeO 2-). The sulfate 4 3 Zr, Hf, Nb, Ta, Sr and Y relative to Ba, Th, U and REEs of group can be completely substituted for selenate in jarosite similar compatibility. Two principal patterns, "Planed" and minerals (NaFe (SO ) (SeO ) (OH) ). Under certain 3 4 X 4 2-X 6 "Ribbed", are characterized by differences in the highly environmental conditions (e.g. pH, ionic strength, anaerobic incompatible elements from Ce–Pr. The two patterns are best environment), bacteria use these metals as potetnial electron distinguished using co-variation diagrams of (La, Ce)/(Nb, acceptors mobilization and reduction from iron hydroxy Rb) vs (U, Th)/(Nb, Rb). sulfate minerals. Several species of bacteria have been Similarities of canonical ratios, Nb/(Th, U, La) and K/U, observed to reduce Se oxyanions to nanoparticulate elemental between MORB and OIB samples and HDFs with "Planed" Se, which is insoluable under most conditions. This pathway patterns suggest that an asthenospheric source for these HDFs potentially poses a vector for mobilization and transport at Se- is plausible. This idea is strengthened by calculating the contaminated sites. The mechanisms pertaining to this composition of sources in equilibrium with "Planed"patterns research along with toxicity thresholds to model organisms of silicic HDFs which range between the DMM and more will be discussed. fertile parts of the convecting mantle. The direct production of

HDFs with "Planed" patterns by melting the asthenosphere [1] Winkel (2011) Environmental Science &Technology 46, with no need for a pre-metasomatized source, avoids the 571-579. circular "chicken and egg" reasoning that has plagued

diamond and kimberlite genesis. Such asthenosphere-derived

enriched fluids can metasomatize the lithosphere to produce

the old and new enriched sources that are needed to explain

the formation of kimberlites and metasomatized xenoliths.

We suggest that the "Ribbed" incompatible-element

pattern in HDFs evolved during percolation of HDFs with

"Planed" patterns through a previously metasomatised lithosphere that carries accessory phlogopite, ilmenite and rutile. HDFs that are trapped in growing diamonds very soon after entry retain their "Planed" trace-element characteristics. If they percolate and interact with the accessory minerals, they acquire the "Ribbed" pattern before they are sealed in microinclusions in diamonds. This model explains the decoupling between major- and trace elements in HDFs and the resemblance of incompatible-element patterns of HDFs from different mantle localities; the averaging of large volumes of mantle rocks smooths the effect of small-scale heterogeneities in the subcontinental lithosphere.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2479

Methylated hopanoid biosynthesis Changes of the GWP due to shifts and function in modern bacteria from flooded to upland rice PAULA V. WELANDER*1, JESSICA N. RICCI2, cultivation 2 3 DIANNE K. NEWMAN AND ROGER E. SUMMONS 1 1 1 S. WELLER *, K. BUTTERBACH-BAHL AND R. KIESE 1 Dept. EESS, Stanford University, Stanford, CA 94305 1 Karlsruher Intitute of Technology, IKM-IFU, 82467 (*correspondence: [email protected]) Garmisch-Partenkirchen, Germany (*correspondence: 2Divs. Biology and GPS California Inst. Technology, [email protected], [email protected], Pasadena, CA 91125 USA 3 [email protected]) Dept. EAPS, MIT, Cambridge, MA 02139 USA

Changes in climate and water distribution resulting in The majority of life’s history has been dominated by physical or economic water scarcity may have severe effects microbes whose metabolic inventions have significantly on rice production systems. Shifting to rotations with non- altered the Earth’s surface environment and, in turn, impacted flooded crops entails pronounced implications in terms of C the evolution of life on Earth. Because unicellular and N element cycling and associated greenhouse gas (GHG) microorganisms do not readily leave diagnostic morphological emissions (CH , N O, CO ). Higher soil aeration in upland fossils, alternative strategies are necessary for studying 4 2 2 systems might decrease CH emissions, but increase N O microbial communities in the context of the Earth’s distant 4 2 emissions (“pollution swapping”) and cause losses in soil past. One predominant strategy is to correlate organic organic carbon that translate into CO emissions [1, 2]. compounds deposited by ancient microbes and preserved in 2 An automated GHG measuring system was set up at the sedimentary rock with lipid molecules produced by extant IRRI farm, Philippines to investigate changes in the total microorganisms. One such class of biomarkers are the GHGs balance when shifting from flooded to upland rice hopanes, pentacyclic triterpenoid lipids that are clearly the cultivation in the dry season under consideration of different diagenetic products of modern day hopanoids. Hopanoids are fertilizer regimes (zero, conventional, improved). The system produced by a diverse set of bacteria and as a result most consists of two analytical sampling units (valve steering and sedimentary hopanes do not provide any taxonomic specificity GCs) connected to a total of 18 chambers (2 treatments, 3 below the domain level. However, hopanoids methylated at fertilizer regimes; 3 replicates). the C-2 or C-3 position are produced by a limited number of The highest global-warming potential (GWP) (kg CO eq bacterial taxa and thus have the potential to function as robust 2 ha-1 season-1) was found for flooded rice without N biomarkers. Traditionally, 2-methyl and 3-methylhopanoids fertilization. Higher N application in irrigated plots resulted in have been utilized as proxies for cyanobacteria and aerobic lower CH emissions. This finding supports theories that methanotrophs, respectively. However, our discovery of the 4 ammonium based fertilizers can decrease CH emissions [3, two proteins necessary to methylate at the C-2 (HpnP) and C-3 4 4]. Total GWPs (CH , N O) were about 70-80% lower in the (HpnR) position revealed that the diversity of bacteria capable 4 2 upland systems due to lower CH emissions but were offset by of producing methylhopanoids was underestimated. 4 lower yields. Subsequent ecological studies of the C-2 methylase have Upland rice cultivation using high yield varieties could shown that alphaproteobacterial copies of the hpnP gene are help to mitigate GHG emissions and reduce water-use in rice found in diverse modern environments while cyanobacterial production systems while further research of N fertilization- hpnP genes are rarer. Further, physiological studies of a C-3 impacts on CH emissions seems necessary. methylase deletion mutant have demonstrated a potential role 4

for 3-methylhopanoids in survival under nutrient limited [1] Reay (2004) Soil. Biol. Biochem. 36, 2059-2065. [2] conditions. Taken together, these studies illustrate that a Stevens & Quinton (2009) Crit. Rev. Env. Sci. Tec. 39, 478- proper interpretation of methylhopanes in the rock record 520. [3] Xie et al. (2010) Plant Soil 326, 393-401. [4] Cai et requires us to look beyond simple taxonomic classification of al. (2007) Soil Sci. Plant Nutr. 53, 353-361. methylhopanoid producers. In addition to understanding which

organisms produce methylated hopanoids, a deeper knowledge of the physiological function and environmental factors that induce their expression in modern cells is needed.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2480 Goldschmidt2013 Conference Abstracts

Integrated analysis of hydrogeologic Gas geochemistry and soil CO2 flux in and biogeochemical processes active volcanic areas, China controlling Technetium mobility at HSIN-YI WEN1, TSANYAO FRANK YANG1, ZHENGFU the Hanford site, GUO2, CHING-CHOU FU1, AI-TI CHEN1 AND MAOLIANG ZHANG2 Washington State, USA 1 Department of Geosciences, National Taiwan University DAWN M. WELLMAN, M. HOPE LEE (*correspondence: [email protected]) 1 AND DANIELLE P. JANSIK 2 Institute of Geology and Geophysics, Chinese Academy of 1902 Battelle Blvd, P.O. Box 999, MS K3-62, Richland, WA, Sciences USA 99354; [email protected]; [email protected], [email protected] Changbaishan intra-plate volcano and Tengchong hydrothermal area are two of the active volcanic areas in Historic nuclear power and weapons operations resulted in China. In order to better understand current status of an enduring legacy of approximately six billion cubic meters magma/hydrothermal activities of the Changbaishan intra- of radionuclide-contaminated soil and groundwater. plate volcano and Tengchong hydrothermal area, we have Technetium (99Tc) is one of the primary risk-driving conducted the soil gas survey and bubbling gas sampling from contaminants and of the most problematic in the environment. hot springs around the Tianchi crater lake and Rehai At the Hanford Site, over 500 Ci of 99Tc was released to the geothermal area. vadose zone as part of past site operations. However, the In Changbaishan volcano, the results show that CO2 is the major component gas for most samples. The maximum value complex hydrogeology of the subsurface and associated 3 4 biogeochemical cycles result in a variety of technical, of helium isotopic ratio of 5.8 RA (where RA = He/ He in air) scientific and financial challenges for 99Tc remediation efforts. implies more than 60% of helium is contributed by mantle The mobility of 99Tc in the geologic medium is mainly a component, while carbon isotope values fall in the range of - result of redox chemistry. Long believed to exist as the 5.8 to -2.0‰ (vs. PDB), indicating magmatic source - signatures as well. Nitrogen dominated samples, 18Dawgo, pertechnatate anion (TcO4 ) and predicted to be highly mobile in the predominantly oxidizing groundwaters, with eventual have helium isotopic ratio of 0.7 RA and carbon isotope value discharge to the Columbia River, 99Tc is one of the site’s of -11.4‰, implying the gas source might be associated with major risk-drivers for remediation.However, recent results regional crustal components beneath 18Dawgo. The first-time 99 systematic soil CO2 flux measurements indicate the flux is ca. have demonstrated the fractionation and persistance of Tc -2 -1 -2 -1 through the existance of three different species. There are two 22.8 g m day and 6.8 g m day at the western and southern primary means by which 99Tc can be immobilized in flank of Changbaishan, which is at the same level as the background value in the Tatun Volcano Group (24.6 g m-2 day- subsurface environments: (1) indirect (abiotic) and (2) direct 1 (biotic). Although much has been learned about the ), implying that Changbaishan may not be as active as TVG. physiology and metabolic potential of single microbial species In Tengchong hydrothermal area, the preliminary results (pure cultures) that immobilize 99Tc, major gaps exist in our show that CO2 is the major component gas for most samples. understanding of the functioning of these and other The helium and carbon isotopic ratio fall in the range of 0.5 RA to 3.5 RA and -4.7 to -1.6 ‰ (vs. PDB), respectively. We microorganisms in natural and contaminated ecosystems. To 18 this end , we will present results of an on-going also analyzed the hot springs water. The "D and " O values multidsicplinary investigation that provides an integrated, fall in the range from -59.8 to 84.6 ‰ and -6.20 to -12.38 ‰ comprehensive understanding of the hydrogeologic, and (vs. SMOW), respectively. Rehai has the highest helium 99 isotopic ratio of 3.5 RA, which implies ca. 40% of helium is biogeochemical processes controlling Tc behavior and fate in 18 complex subsurface system. This information is further being mantle-derived. The "D and " O results implied the water in used to develop tools that integrate the chemical and this area was affect by primary magmatic water. Nevertheless, biological reaction network influencing the mobility of 99Tc in samples from Banglazhang and Shihchiang hydrothermal the subsurface. areas show much lower helium isotopic ratio of 0.8 RA and 0.5 RA, respectively. It suggests that the local tectonic setting plays an important role for the gas degassing in this area.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2481

Geochemical characterization of Mojave Crater, Mars: tire-wear particles One meteorite source crater M. WENZEL1*, V. DIETZE 2, P. STILLE3 AND R. GIERÉ1 S.C. WERNER1, A. ODY2 AND F. POULET2 1Institut für Geo- und Umweltnaturwissenschaften, Albert- 1Centre for Earth Evolution and Dunamics, University Of Ludwigs-Universität, 79104 Freiburg, Germany, Oslo, Norway ([email protected]) (*correspondence: [email protected] 2 Institut d’Astrophysique Spatiale, Université Paris-Sud, freiburg.de) 91405 Orsay cedex, France. 2Deutscher Wetterdienst, Zentrum für Medizin- Meteorologische Forschung, Referat Lufthygiene, 79104 The Mojave Crater on Mars has a diameter of about 55 Freiburg, Germany, ([email protected]) km; it is situated at 7.5˚N and 33.0˚W at the joint of Simud 3Laboratoire d’Hydrologie et de Géochimie de Strasbourg, and Tiu Valles in Xanthe Terra. It attracted attention for its Université de Strasbourg, UMR 7517 CNRS, 67084 well preserved landforms resembling the morphology of Strasbourg, France, ([email protected]) alluvial fans in arid environments, and suggesting a very young formation age. However, because of its large size, Tire-wear particles are a basic component of common road speculations on the age range from late Hesperian to late dust present in urban environments, and their annual emissions Amazonian age. to the environment in Germany are reported to be 60 x 106 kg From crater count statistics technique, we here [1]. The knowledge of their basic characteristics can be useful demonstrate that Mojave formed only 2-4 Ma ago. Such a to trace tire material in environmental dust samples and for the young age makes it a prime candidate for being the ejection evaluation of possible health effects related to the inhalation of source of seveal groups of martian meteorites. Additional tire-wear particles. For this study, we analyzed particles potential links (site mineralogy and presence of an extended generated in a closed indoor tire test rig at the Bundesanstalt ejecta ray pattern) between this crater and the SNCs will be für Straßentechnik (BAST) from three car tires as well as discussed. particles generated by cryogenic milling of shredded waste Because Mojave formed on old Noachian terrain, it tires. questions the original crystallization age of shergottites. A 4.1 Particles ranging in size from 0.2 µm to 25 µm were Gyrs old was inferred by debated Pb-Pb isotope ratios characterized with a scanning electron microscope (SEM). All (Bouvier et al. , 2008, EPSL 266, 105-124; Bouvier et al. , samples contained particles with diameters <0.6 µm. 2013, LPSC No. 1719), whereas some apparently young According to their morphological and chemical features the crystallization ages (173-596 Ma, Mars Meteorite particles were divided into characteristic groups. The bulk Compendium, JSC Pub. No. 27672, the latter is Tissint, which chemical composition of each sample was distinct, with the is the oldest, Brennecka et al. , 2012, 75th Met Soc abstract total carbon content varying between 28.73 and 83.75 wt%. No 5157) are more commonly accepted. We will attempt to Inductively coupled plasma mass spectrometry (ICP-MS) data reconcile our observations with the debate about the age of revealed significant variability in the contents of various trace shergottites. elements (e.g. Pb 3.4 ppm - 437.2 ppm). Characteristic among all samples was a very high Zn content (> 1100 ppm). In addition, the ratios of 87Sr/ 86Sr, which varied from 0.7089 to 0.7094, and of 204Pb/ 206Pb, with values between 0.0560 and 0.0570, were found to be characteristic for the tire-wear particles, but differed from the ratios measured for the shredded tires. Comparison of the Pb isotope ratios with literature data [2, 3] from road-related dust samples (e.g. pavement particles or brake-wear) and traffic-related lead sources (e.g. batteries or gasoline) showed that Pb isotope ratios could be used as a tracer for the tire-wear contribution to road dust.

[1] Baumann & Ismaier (1998) KGK 51, 182-186. [2] Wijaya et al. (2012) J Geochem Exploration 118, 68-76. [3] Monna et al. (1997) ES & T 31, 2277-2286.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2482 Goldschmidt2013 Conference Abstracts

Interaction of corroding iron with Insights into U-series weathering bentonite at repository conditions chronometers from size fraction P. WERSIN1*, A. JENNI1 AND U.K. MÄDER1 distribution of U and Th nuclides in 1Insitute of Geological Sciences, University of Bern, 3012 Himalayan soils and sediments Bern, Switzerland (*[email protected]) 1 A. JOSHUA WEST

Iron canisters containing high-level nuclear waste 1University of Southern California, Department of Earth surrounded by swelling bentonite backfill are foreseen to be Sciences, 3651 Trousdale Parkway-ZHS 117, Los emplaced in geologic formations. Corrosion will release Fe(II) Angeles, CA 90089 UNITED STATES; species which will interact with the bentonite. This may ([email protected]) induce cementation and clay mineral transformations. The details of this process are still poorly understood. In an in-situ As a result of varying mobility between different nuclides, experiment (ABM-1) at the Äspö Hard Rock Laboratory disequilibria within the U-series decay chain potentially (Sweden), compacted bentonite materials in contact with steel provides valuable constraints on the timescales of Earth were exposed to temperatures up to 140°C for 2 years. After surface processes. Models describing the evolution of both overcoring, clay samples in contact with the Fe were sampled (234U/238U) and (230Th/238U) activity ratios during leaching are and analysed with microscopic techniques and µ-Raman increasingly used to determine the duration of weathering and spectroscopy. Both sides of an Fe metal structure, the Fe-water sediment transport. However, important assumptions in these and the Fe-clay interfaces were studied. models remain untested. While the basic mechanisms driving The Fe-water side reveals a 100-200 µm thick corrosion observed disequilibria during weathering are well-established layer conposed of magnetite, siderite, hematite, hydrous ferric (e.g. alpha recoil and preferential leaching), the picture oxide. The Fe-clay side exhibts a web-shaped '100 µm thick remains somewhat fuzzy in terms of how bulk rocks, soils, layer of iron corrosion products (bright) and clay (dark). and sediments, and the complementary dissolved phase, Siderite and Fe oxyhydroxides could be identified. The clay actually acquire their U and Th signature. Important puzzles, matrix is somewhat enriched in Fe and partly also in Mg, but such as the reason for 234U enrichment of some bulk solid no change in A/Si ratio was noted. At a distance of about 1 phases despite the expected more rapid leaching of this

mm from the metal formation of CaSO4 is observed. The front nuclide, have yet to be completely resolved. enriched in Fe exends 1-2 mm into the clay. Overall, the data This study focuses on measurements of the U and Th suggest an intimate association of iron corrosion product and nuclide abundance in a suite of samples (rocks, soils, montmorillonite, but no formation of Fe silicates. sediments, and stream water) from the Middle Hills of Nepal, where solid products of weathering show distinct depletion in soluble elements (e.g. Ca, Na). Bulk soils and sediments have (234U/238U) above equilibrium ("234U=+15-30‰ relative to equilibrium), increasing with weathering extent in the soil profiles. Variability in 234U/238U between size fractions of the Nepal soils demonstrates that the 234U enrichment can be quantitatively explained by retention in the very fine (<0.2µm) fractions, which have measured "234U>+100‰ and REE patterns characteristic of Fe-oxides. These results suggest that bulk solid phase (234U/238U)>1 can result from modern weathering processes because of retention in oxide phases. Figure 1. Back scatter image showing a web-shaped iron Observed (230Th/238U) is highly variable and would imply corrosion-clay layer contacting the Fe surface (far left). long (tens to hundreds kyr) weathering duration based on simple models of leaching and decay. These durations require residence times that are inconsistent with the depth of weathering profiles and erosion rates inferred from 10Be inventories in quartz from these locations. One possible explanation is that the measured sediment (230Th/238U) from these sites may be strongly influenced by grain size sorting.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2483

Mo isotope signature of OAE 2 New U-Pb age and �Hf signature S. WESTERMANN1-2*, D. VANCE1, V. CAMERON2, data of metassedimentary and C. ARCHER1 AND S.A. ROBINSON3 metabasic rocks of the front of the 1Institue of Geochemistry and Petrology, Dept. of Earth Southern Brasilia Orogen, south of Sciences, ETH Zurich, Switzerland 2Bristol Isotope Group, School of Earth Sciences, University São Francisco Craton, Brazil of Bristol, UK. 1 1 A. WESTIN * AND M. C. CAMPOS NETO 3Dept. of Earth Sciences, University College London, UK. 1 (* correspondence: [email protected]) Geosciences Institute, University of São Paulo, São Paulo, SP, Brazil (*correspondence: [email protected]; Understanding variations of redox conditions during [email protected]) oceanic anoxic events (OAEs) is of primary importance, particularly as recent observations and modelling have shown The Brasília Orogen, located on the western and southern that processes invoked to explain the origin of OAEs are being margin of the São Francisco Craton, corresponds to a observed today as a consequence of anthropogenic change. horizontal nappe stack that was regionally transported Here, we compare redox-sentsitive trace metal (RSTM) eastward during the collision between the Paranapanema and distributions and molybdenum (Mo) isotope variations during Goiás Central Blocks and the Sanfranciscan Plate in the a major Cretaceous OAE (OAE 2, Bonarelli event) within the Ediacaran Period [1]. The front of the Southern Brasília western Tethys and the Northern Atlantic. Whereas RSTM Orogen is represented, at the base, by metassediments with have the potential to provide insights regading local lithic nature associated with amphibolite lenses, both objects depositional conditions and processes in paleoceanographic of this study, followed by metapsamites and metapelites of the systems, Mo-isotope data can, under certain circumstances, Carrancas Group, with a tectonically upper exotic unit of provide quantitative estimates of how the extent of seawater metawackes [2, 3]. anoxia may have fluctuated in the past. The metassediments of the base are paragneiss rich in The RSTM contents indicate more reducing conditions lithic fragments that vary from plagioclase-quartz-biotite- during the OAE 2 interval, reaching from suboxic to euxinic epidote gneiss with potassic feldspar and hornblende (EG) to conditions. The RSTM enrichment factors (EFs) also suggest epidote-plagioclase-biotite-quartz gneiss with carbonate (QG). different depostional conditions and paleoceanographic Detrital zircons from EG rocks provided U-Pb ages (LA MC processes between the Tethys and the North Atlantic. Whereas ICP MS) that range between 2.04 to 2.18 Ga, with mean peak the North Atlanic sites show evidence of weak watermass age of 2.12 ± 13 Ga. The �Hf values of this crystals vary from restriction associated with the action of a particulate shuttle -10.4 to +15.1, with predominance of the positive values. within the water column, the EFs of the Tethyan sections are Detrital zircons from the QG rocks indicated a provenance age characteristic of unrestricted marine systems. between 2.00 to 2.19 Ga, with mean peak age of 2.03 ± 11 Ga. Mo isotopes show surprisingly negative values along the The �Hf values range from -7.4 to +6.2, with prevalence of Tethyan sections. At the onset of OAE 2, an increasing trend the negative values. in "98/95Mo is observed with values ranging from -0.6 to 0.6 The amphibolite lenses are descontinously interbedded ‰. During the 2nd half of OAE 2, the "98/95Mo curve shows a with the paragneiss, predominantly formed by hornblende and progressive shift towards more negative values. In the North plagioclase (andesine), with tholeitic signature. The mean Atlantic, Mo isotopes are generally heavier during OAE 2, peak age of this rocks stands in 1.96 ± 22 Ga and the �Hf fluctuating around an average value of 1.1 ‰. values vary from -16.8 to +23.5. Both the western Tethys and the Northern Atlantic sites These data suggest that the deposition of the show redox variations, reaching anoxic/euxinic conditions. metassedimentary sequence iniciated after 2.0 Ga, with the However, light "98/95Mo values in the western Tethys suggest related basic magmatism starting somewhat around 1.96 Ga. redox conditions may not have been fully euxinic. For the The �Hf values also suggest that the source area comprised North Atlantic, our results are consistent with fully euxinic rocks related to juvenile accretion and rocks having long conditions and may help to improve our understanding of the crustal residence. global extent of euxinia during OAE 2. [1] Campos Neto, M. C. (2000) Tect. Evol. S. America, 335- 365. [2] Campos Neto et al, (2011) JSAES 32, 393-406. [3] Westin e Campos Neto (submitted article) JSAES.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2484 Goldschmidt2013 Conference Abstracts

Impacts of geothermal energy storage Reduced C-O-H Volatiles Dissolved on the microbial community in Lunar Picritic Glasses composition and activity in shallow D.T.WETZEL1*, M.J. RUTHERFORD1, S.D. JACOBSEN2, systems E.H. HAURI3, A.E. SAAL1, AND S.-M. THOMAS4 1 1 2 1 Dept. of Geological Sciences, Brown University, Providence, ANKE WESTPHAL , ANNA JESUßEK , TOBIAS LIENEN , 2 1 RI 02912 (*correspondence: [email protected]) ANDREAS DAHMKE AND HILKE WÜRDEMANN 2Dept. of Earth and Planetary Sciences, Northwestern 1 Helmholtz Centre Potsdam, German Research Centre for University, Evanston, IL 60208 Geosciences GFZ, [email protected] 3DTM Carnegie Institute of Washington, DC 20015 2 Christian Albrechts Universität zu Kiel, [email protected] 3Dept. of Geoscience,University of Nevada Las Vegas, Las Vegas, NV 89154 To investigate the effects of temperature change due to geothermal energy storage on the microbial communities and The Moon had long been considered dry, until recently,

the fluid geochemistry, soil column experiments using aquifer when Saal et al. [1,2] used SIMS to measure H2O dissolved in sediment and acetate added water were performed at 10, 25, the lunar picritic glasses. Before this discovery, carbon was 40 and 70°C. Genetic fingerprinting revealed a change in considered the primary volatile. The formation of a CO-rich microbial community composition and activities due to gas phase by graphite oxidation was thought to drive fire elevated temperatures. The highest DNA amount and sulphate fountain eruptions on the Moon producing the glass beads [3]. reducing bacteria (SRB) specific gene copy number were The natural lunar glasses contain too little dissolved C (below observed in fluids of the 40°C column. Correspondingly, the detection limits) to be detected by FTIR spectroscopy. We highest sulphate reduction rate was detected at 40°C. Thus used the Apollo 15 green glass composition to experimentally probably the highest number of SRB was present in this determine the solubility and speciation of C in H-bearing column. Due to the formation of different redox zones in the graphite-saturated melts. Our experiments show C dissolves in

10°C column, zones of microbial colonization were observed. reduced lunar melts (fO2

In the entrance nitrate and iron reducers were identified, lesser extent CH4. Under more oxidizing conditions (fO2>IW- whereas at the outlet fermentative bacteria dominated. At 0.55), we find C is dissolved as carbonate in lunar picritic 70°C sulphate reducing conditions predominated and no melts. We also determine that twice as much C can be zoning of microbial colonization was detected. Genetic dissolved in oxidized melts compared to the reduced melts. fingerprinting revealed the dominance of SRB and NanoSIMS measurements [1] of natural glasses suggest fermentative bacteria. Methane production was found at 25°C, that hydrogen is dissolved in large enough quantities (up to only. Accordingly, quantification with quantitative polymerase ~40 ppm) to be detectible by FTIR spectroscopy. We used chain reaction (qPCR) proved the highest number of the Raman and FTIR spectroscopy to study the speciation of H in dominant methanogen Methanosaeta concilii. the natural orange, yellow, and green lunar glasses. We also calculated the absorption coefficients for each glass composition based on our experiments. The synthetic sample spectra were also used as a guide to baseline correct and locate the weak O-H stretching peak in the natural samples. With this work, we are able to determine the abundance and speciation of dissolved volatiles in lunar and other reduced high FeO melts and the effect of planetary degassing on the evolution of an early atmosphere.

[1] Saal A.E. et al. (2008) Nature, 454, p.192-95. [2] Saal A.E. et al. (2009) Goldschmidt Conf., Abst. #A1139. [3] Sato M. (1976) PLSC 7th, p.1323-25.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2485

Lithium isotope variation in waters Regional-scale metasomatism in the and sediments from lake Donggi Fortescue Group volcanics, Cona and its catchment, China Hamersley Basin, Western Australia, M. WEYNELL1*, U. WIECHERT1 AND J.A. SCHÜSSLER 2 constrained through phase equilibria 1Freie Universität Berlin; Germany (*correspondance: modelling [email protected]) A.J.R. WHITE*, M. LEGRAS, R.E. SMITH 2GFZ German Research Centre for Geosciences, Helmholtz AND P. NADOLL Centre Potsdam, Potsdam, Germany CSIRO Earth Science and Resource Engineering, Australian Lithium isotopes are a tracer of weathering at the Earth’s Resources Research Centre, 26 Dick Perry Avenue, surface, as documented from catchments with basaltic Kensington, WA 6151, Australia (*correspondance: [e.g., 1], granitic [e.g., 2] and mixed (carbonate, volcanic and [email protected]) sedimentary) lithologies [e.g., 3]. In this study we examine the behaviour of lithium (Li) and its isotopes in the catchment of Mafic to intermediate volcanic rocks of the Fortescue lake Donggi Cona, China, which is an open oligotroph Group form the lowermost stratigraphic unit of the 100,000 freshwater lake in the northeastern part of the Tibetan Plateau. km2 Hamersley Basin on the southern margin of the Archaean The main inflow drains an area with a high proportion of Pilbara Craton, Western Australia. A regional burial carbonate rocks and a second inflow is sourced from a metamorphic gradient extends across the basin from prehnite- catchment with a larger quantity of silicate rocks. In addition, pumpellyite facies in the north to greenschist facies in the warm springs contribute to the Li budget of the lake. Water south [1]. Superimposed on this metamorphic gradient is a chemistry is mainly controlled by carbonate dissolution. With heterogeneous distribution of metasomatized rocks the exception of spring waters, pH values are constant at ~8.8. characterized by pumpellyite±epidote+quartz assemblages. The dissolved load (DL) of every compartment shows distinct Whole-rock geochemical data indicate metasomatism is !7Li values (relative to L-SVEC): main inflow +17.0 ; minor associated with significant depletions in alkali elements, Mg inflow +20.7 ; warm springs +11.5 and lake +16.9. Suspended and first transition series metals, with enrichments in Si and loads and river sediments give !7Li values from -2.1 to +3.1. Ca. Such geochemical trends are compatible with sub-sea However, lake sediments exhibit a narrow range of -1.1 to -0.5 floor hydrothermal circulation [2]. for distal sample locations. Detrital influenced lake sediments Phase equilibria modelling with the program 7 show positive ! Li values of +1.7 and +2.9. Li concentrations THERMOCALC [3], in subsets of the model system Na2O- (DL) are 37 ng/ml in the lake, 7 to 12 ng/ml in the main CaO-K2O-FeO-MgO-Al2O3-SiO2-H2O-Fe2O3 inflow, 33 ng/ml in the second inflow and 125 ng/ml in warm (NCKFMASHO), place P-T constraints on the conditions of spring waters. Li concentrations of suspended loads and regional metamorphism and regional-scale metasomatism. sediments are in the range of 20 to 55 µg/g. Lithium ‘Least altered’, regional metamorphic rocks show a concentrations and isotope ratios of the lake can be explained temperature gradient from <200°C in the north, to > 325°C in by mixing of waters from the 3 sources and by evaporation. south, consistent with predicted burial-derived thermal High !7Li values (DL) in the tributaries can be explained by gradients [1]. Highly altered, metasomatized rocks show incorporation of light Li into secondary minerals formed in the consistent temperatures of 275 – 300°C, and pressures > 2.5 catchments, which is consistent with low !7Li values of kbar, across the entire basin. complementary sediments and suspended loads. However, The calculated temperature for the metasomatized rocks is compared with basaltic catchments, e.g. [1], Li concentrations interpreted to represent the temperature under which in the waters are higher and !7Li values are lower. We suggest hydrothermal alteration occurred. The consistent P-T estimates that this is due to a distinguished lithology and lower soil and geochemical data suggest a common hydrothermal event formation rates controlled by the climatic regime on the acting across the entire Hamersley Basin, covering length northeastern Tibetan Plateau. scales of hundreds of kilometres. This has important implications for the size of metasomatic systems in other [1] Vigier et al. (2009) EPSL 287, 434-441; [2] metamorphic terranes. Lemarchand et al. (2010) GCA 74, 4612-4618; [3] Millot et al. (2010) GCA 74, 3897-3912. [1] Smith et al. (1982) J. Pet 23, 75-102. [2] Hannington et al. (2003) Miner Deposita 38, 393-422. [3] Powell & Holland (1988) J. Met. Geol. 6, 173-204.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2486 Goldschmidt2013 Conference Abstracts

Towards better Greenland source Indium’s aqueous behavior in a attribution for IRD via Pb-Pb in stream influenced by acid mine feldspar and Ar-Ar in amphibole drainage WHITE. L1*, STOREY. C1, BAILEY. I2 AND FOSTER. G2 SARAH JANE O. WHITE1,2,*, FATIMA A. HUSSAIN2, 2 3 1 HAROLD F. HEMOND , ROBERT L. RUNKEL , KATHERINE University of Portsmouth, Burnaby Road, Portsmouth. WALTON-DAY3 AND BRIANT A. KIMBALL4 (*Presenting Author: [email protected]) 2University of Southampton, European Way, Southampton. 1Harvard School of Public Health, 401 Park Dr, Boston, MA 02215 (*correspondence: [email protected]) A major uncertantity in future climate predictions involves 2MIT, 15 Vassar St, Cambridge, MA 02139 changes in the mass and areal extent of the Greenland ice 3U.S. Geological Survey, Denver Federal Center, Box 25046, sheet (GrIS) and its variability in a warmer climate. MS 415, Denver, CO 80335 Understanding the growth of the GrIS during Pliocene 4U.S. Geological Survey, 2329 West Orton Circle Salt Lake intensification of northern hemisphere glaciation may enable City, Utah, 84119 the critical evaluation of existing models and aid in future validation of these models. The provenance of Ice rafted Indium is an increasingly important metal in debris (IRD) deposited in marine sediments has great potential semiconductors and electronics, and its use is growing rapidly to fingerprint regions of present and past iceberg calving in the as a semiconductive coating (in indium tin oxide) for LCD coastal zones of continental margins. As such, this could displays, flat panel displays, and photovoltaic cells. It also has potentially be a poweful technique when confining the extent uses in important energy technologies such as LEDs. Despite of the GrIS during past climatic intervals. However, the IRD its rapid increase in use, very little is known about indium’s record is only as strong as the onshore land-based record of environmental behavior, and concerns are emerging over its potential sources. health impacts. Two minerals common within IRD that have been used One significant flux of indium to the environment is from previously and that show great promise in this regard are nonferrous mining and smelting. Mineral Creek is a headwater feldspar and amphibole. Pb isotopes in feldspar record a stream in southwestern Colorado that is severely affected by diagnostic signature of the continental crust within distinct heavy metal contamination as a result of acid mine drainage. geologic terranes. In particular, Greenland is composed of a This includes indium concentrations that are 10,000 times number of distinct terranes with proven distinct Pb isotope those found in natural rivers. There have been a variety of signatures. Ar-Ar dating of amphiboles records the thermal remediation efforts in this watershed, including the installation history of a terrain when it was metamorphosed above or of bulkheads to reduce water flow from mining tunnels, and cooled below c. 550oC. Due to distinctive metamorphic removal of tailings piles. These remediation efforts appear to histories within different terranes this signature is also have reduced metal loadings in the system, though they potentially diagnostic of a particular source area. The two remain above chronic aquatic standards. Indium, however, minerals together could be particularly powerful but only if has not been previously measured, and no standards exist for the potential areas of calving are well-characterised. indium in natural waters. In this work, a pH modification Here we present data from fluvio-glacial sediments from experiment was conducted in August 2005 to investigate the sites around the margins of Greenland and discuss their effects of an active remediation proposal to increase the pH of diagnostic characteristics. We then compare these diagnostic the creek. At the existing pH of ~3, indium concentrations are geochemical signatures to some circum-Greenland core top 6-29 µg/L (10,000x those found in natural rivers), and exist IRD samples from numerous offshore sites, acting as a proof completely in the dissolved phase. Upon raising the pH of the of concept. Finally, we present data sets from Mid Pliocene system to > 8, all of the indium became associated with the IRD from ODP Site 907, from numerous depths and time suspended solid phase, primarily due to sorption to iron- intervals, to further develop the proposed method and apply it oxides. This work informs how much indium may be to a key period in the development of northern hemisphere mobilized from nonferrous mine wastes globally, and provides glaciation. much-needed data about the aqueous behavior of indium.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2487

Radioactivity and Neutrino Ion imaging and ion tomography Production in the Oceanic Crust applications in zircon geochronology WILLIAM M. WHITE1 M.J. WHITEHOUSE1* 1Dept. of Earth & Atmospheric Sciences, Cornell University, 1Swedish Museum of Natural History, SE-104 05 Stockholm, Ithaca, NY, 14853 USA, ([email protected]) Sweden (*correspondence: [email protected])

Most oceanic crust is created at mid-ocean ridges as High spatial resolution secondary ion mass spectrometry magma rises from the mantle to fill the gap between diverging (SIMS) has been routinely used in zircon U-Pb geochronology plates. This produces a relatively uniform crustal structure and and geochemistry for three decades and has been central to composition. The upper km of so of the crust consists of many important geological discoveries. The unique ion basaltic lavas (called mid-ocean ridge basalts or MORB) microscope capability of the CAMECA IMS 1270/80 characterized by low concentrations of incompatible element, instruments, in particular using scanning ion imaging (SII) including the heat producing elements U, Th, and K. coupled with high sensitivity, high mass resolution and Concentrations show a highly skewed distribution; log-normal exceedingly low noise ion-counting multicollection remains means (which provide an estimate of the modal however, a relatively underutilised tool in geochronology. concentrations) are U= 94 ppb, Th = 273 ppb, and K = 1211 A recent study [1] of Meso- to Paleoarchean zircon from ppm, while mean concentrations are U = 119±26 ppb, Th = gneisses in east Antartica which have experienced ultra-high 404±77 ppb, and K = 1328±71 ppm (quoted uncertaintly is 2 temperature (UHT) metamophism, used scanning ion imaging standard errors of the mean based on ~2000 analyses; from (SII) both to map the occurrence and measure the isotope ratio Gale et al. , G3, 14, 2013). Back-arc basin basalts have similar of unsupported radiogenic Pb. Numerous micrometre-sized Th but higher U and K: 137 ppb U, 399 ppb Th, and 2258 ppm Pb-rich clots were revealed in an 80 x 80 µm imaged area by K. The compositions of MORB indicates that they evolve the SII technique. These clots are independent of the through fractional crystallization within the oceanic crust and distribution of other elements, notably U and Y, both of which hence do not represent the composition of the crust as a whole. show simple oscillatory zoning, while their elevated Calculations based on the MELTS thermodynamic model 207Pb/206Pb ratios clearly indicate their antiquity. Apart from suggests MORB have experienced an average of 39% explaining commonly observed Pb instability and reverse fractional crystallizaiton. Assuming that the composition of discordance [2] during SIMS analysis of UHT zircon, such the bulk ‘fresh’ oceanic crust is that of a primitive parent in ancient Pb redistribution can have implications for the equilibrium with mantle olivine, bulk ‘fresh’ oceanic crust is geochronology of zircon from the early Earth [1]. estimated to have 80 ppb U, 260 ppb Th, and 875 ppm K. The lateral resolution of an SII analysis is limited to the Simple mass balance then indicates that ‘fresh’ lower oceanic ca. 2 µm diameter of the primary beam and so the actual size crust (gabbroic section or layer 3) has 70 ppb U, 220 ppb Th, of the Pb-enriched clots remains essentially unconstrained and 750 ppm K. Assuming the crust is generated by 8% below this level, but is clearly considerably smaller given the melting, this implies depleted mantle concentrations of 6 ppb relative uniformity in observed clot area. In an extension of U, 21 ppb Th, and 70 ppm K. Hydrothermal processes modify the conventional SII study, an investigation of UHT zircon the composition of oceanic crust, increasing K and U by 402 from southern India that exhibit similar Pb-clots, utilised a mg/kg and 0.307 mg/kg, respectively (Staudigel, TOC, novel combination of SII and depth profiling, here termed Chapter 13, 2013). This increases U and K in the bulk oceanic scanning ion tomography (SIT), to add a third dimension to crust to 110 ppb U and 1280 K. A small fraction of the the Pb clots. During a typical SII analysis (comprising 100 oceanic crust consists of thick ocean plataeus produced by scans), the ion beam penetration is < 5 nm and using this melting over mantle plumes. These plateau basalts have higher method, Pb-rich clots are revealed to have a size typically of U, Th, and K concentrations: ~400 ppb U, ~1300 ppb Th, and only a few nanometers. The ability of SIT to reveal the true ~1369 ppm K. Considering all these factors considered and length-scale of Pb-isotope redistribution, while still uniquely assuming an average crustal thickness of 7 km for crust recording a Pb isotope ratio, considerably aids in constraining created at mid-ocean ridges, total U, Th, and K in the oceanic models for the processes involved in their generation. crust is estimated at 6.62 x 1014 kg, 1.55 x 1015 kg, and 762 x 1018 kg, respectively, producing 0.13 TW of energy (-1% of [1] Kusiak et al. (2013), Geology 41, 291-294. [2] Williams et the terrestrial total). These masses of U and Th would produce al. (1984), Contr. Min. Petrol 88, 322-327. 3.9 x 106 anti-neutrinos per year.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2488 Goldschmidt2013 Conference Abstracts

Persistence of early Archean style of Increasing greenhouse gas emissions crustal growth and near-chondritic in circumpolar regions due to climate mantle into the late Archean change-induced permafrost retreat 1 2 1 2 2 M.J. WHITEHOUSE * AND A.I.S. KEMP M. WHITICAR* J. BHATTI AND N. STARTSEV 1Swedish Museum of Natural History, SE-104 05 Stockholm, 1 SEOS, U. Victoria, Victoria, BC, V8W 2Y2, Canada Sweden (*correspondence: [email protected]) (*correspondence: [email protected]) 2University of Western Australia, Crawley, WA 6009, 2 NFC, Canadian Forest Service, Edmonton, AB, Canada Australia ([email protected]) Thawing permafrost peatlands substantially influence The Neoarchean Lewisian Complex of north-west northern ecosystems by changing the regional hydrology and Scotland is one of the most extensively studied TTG gneiss mobilizing the vast carbon (C) reserves that results in terranes on Earth. It has been used to propose and refine increased greenhouse gas (GHGs) emissions to the models of crustal evolution for over a century, from the early atmosphere. With permafrost distribution controlled largely by recognition of multiple phases of crustal reworking based on topography and climate, our IPY study intensively monitored cross-cutting dykes [1] to the more recent “terrane models” the local C-cycling processes and GHG fluxes associated with proposed for crustal accretion [2]. Interpretation of both different hydrologic and permafrost environments at 4 sites geochronology and isotopic data from the Lewisian, however, along a latitudinal climatic gradient of mid-boreal, boreal, low remains complicated (e.g. [3]) by polyphase metamorphism, and high subarctic ecoclimatic regions that extend south-north which in places attains granulite facies. from the Isolated Patches Permafrost Zone (northern Alberta), In this study, we present cathodoluminescence image- to the Continuous Permafrost Zone (Inuvik, NWT). Each site guided ion microprobe U-Th-Pb geochronology and LA-ICP- encompasses a local hydrologic and vegetation gradient from MS Hf isotopes of zircon separated from representative TTG upland forest and peat plateau to collapse scar. gneisses across the Scottish mainland and Outer Hebridean Our multi-year measurements of peatland profiles and flux

Lewisian outcrop. Applying a similar methodology to that chambers for CH4 and CO2 concentrations and stable isotope outlined in [3], we assign a preferred magmatic protolith age ratios indicate processes, including methanogenesis, to each zircon population and this age is then used to calculate methanotrophy, transport and emission that control the

#Hf(t) values. distribution of these GHGs. These relationships are modulated Over a wide range of protolith ages from > 3.1 Ga to 2.7 by fluctuating local soil water and ecosystem conditions. The

Ga, zircon #Hf(t) values are, on average, only slightly super- gas geochemistry shows that significant surface CH4 chondritic and show relatively little variation with time. A production occurs by both hydrogenotrophic and methyl- possible explanation for this trend is that younger TTG fermentative methanogenesis in submerged, anaerobic peats, magmas are increasingly influenced by recycling of older e.g., collapse scars, whereas methane oxidation is restricted to crust, although few older zircon cores are observed to support aerobic, drier environments, e.g., upland sites and peat- such an ad hoc interpretation. As an alternative, we propose a atmosphere interface. The most active methanogenesis and tectonic model for the Lewisian in which mafic precursors to emissions are in the actively thawing permafrost sites the TTG magmas, generated from a mildly depleted to near- contrasting with those under continuous permafrost. This chondritic mantle, were rapidly recycled over a period of degree of methanogenesis is being amplified by the increased >400 Ma with little or no direct input of typical rate of warming and the rapid retreat of permafrost in contemporaneous depleted-mantle. Similar tectonic scenarios, Canada’s northern areas (ca. 2.5 km/yr). differing markedly from “modern-style” plate tectonics, have For context, the present permafrost and GHG emission

been proposed for the early Archean (e.g. [4]) and our situation is compared with the rapid rises in temperature, CH4

observations from the Lewisian TTG gneisses suggest that, at and CO2 concentrations during the Younger Dryas-Preboreal 13 least locally, similar processes, as well as near-chondritic transition (~11.5yBP). Our pCH4 and " CH4 work [1] on

mantle, may have persisted into the Neoarchean. Pakitsoq, Greenland ice show that the rapid rise in pCH4 during YD-PB is unlikely to have been due to massive marine

[1] Peach et al. (1907), Mem. Geol Surv. GB. [2] Kinny et al. gas hydrate release (‘clathrate gun’), but that CH4 from (2005), !"# $%&'"# (&)"# *&+," . [3] Whitehouse & permafrost retreat after Last Glacial Maximum is a plausible Kemp (2010), Geol. Soc. Lond. Spec. Publ. 335, 81-101. [4] explanation. ! #$%"! #&'(#)$ Naeraa et al. (2012), Nature 485, 627-630. [1] Schaefer, et al. (2006) Science 313, 1109-1112.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2489

Absorbing aerosol radiative effects in Stable Sr isotope fractionation in the limb-scatter viewing geometry synthetic barite A. WIACEK1, R. V. MARTIN2,3, A. E. BOURASSA4, INOKA H. WIDANAGAMAGE1, ELIZABETH M. GRIFFITH2, N. D. LLOYD4 AND D. A. DEGENSTEIN 4 AND HOWIE D. SCHER3 1 Division of Engineering, Saint Mary’s University, Halifax, 1 Department of Geology, Kent State University, Canada [email protected] 2 Department of Physics and Atmospheric Science, Dalhousie 2 Department of Earth and Environmental Sciences, University University, Halifax, Canada of Texas at Arlington, [email protected] 3 Harvard-Smithsonian Center for Astrophysics, Cambridge, 3 Department of Earth and Ocean Sciences, University of Massachusetts, USA South Carolina, [email protected] 4 Department of Physics and Engineering Physics, University

of Saskatchewan, Saskatoon, Canada Barite (BaSO4) is a highly stable and widely distributed mineral that incorporates many elements (e.g., Sr, Ca, Ra) in We use the fully 3-D radiative transfer code SASKTRAN its crystal lattice making it useful as an archive for to simulate the sensitivity of limb-scatter viewing geochemical and isotopic signals of environmental change. Odin/OSIRIS satellite measurements to absorbing mineral Abiotic precipitation of barite commonly occurs with mixing dust and carbonaceous aerosols, and to sulfate aerosol and ice of sulfate and barium rich solutions. Barite can also precipitate in the upper troposphere. in association with biological processes, such as bacterial At short wavelengths (337 nm, 377 nm, 452 nm), we sulfide oxdiation. We present stable Sr isotope results ("88Sr) found that the addition of any aerosol species to an air only from synthetically precipitated barite to elucidate the atmosphere caused a decrease in single-scattered radiation due parameters (e.g., temperature, barite saturation state, solution to an extinction of Rayleigh scattering in the direction of Sr/Ba) influencing mass dependent Sr isotopic fractionation OSIRIS. The reduction was clearly related to particle size under abiotic conditions. This work will constrain future first, with absorption responsible for second-order effects studies of stable Sr isotopic fractionation in natural only. Multiple-scattered radiation could either increase or biologically-influenced barite precipitation. decrease in the presence of an aerosol species, depending both We precipitated barite from solution by adding sulfate to a on particle size and absorption. The combined effect led to Sr-Ba solution under various conditions (solution Sr/Ba, complex total radiance signatures that generally could not temperature, and barite saturation state) that may influence unambiguously distinguish absorbing versus non-absorbing equilibrium and/or kinetic mass dependent stable Sr isotopic aerosols. However, we found that scene darkening above the fractionation. Isotopic measurements were made on a Thermo aerosol layer is unambiguously due to absorption whereas Neptune Plus MC-ICPMS at the University of South Carolina scene darkening within and below the aerosol layer can simply using a standard-sample bracketing technique that corrects for be the result of a reduction in single-scattered radiance. instrumental mass bias relative to a Zr reference ratio. All However, the effect did not exceed 0.2% of the total radiance barite samples were less enriched in 88Sr relative to the due to air only for medium-sized carbonaceous aerosols. solutions from which they precipitated similar to other isotope A fortuitous, unexpected implication of our analysis is that systems (e.g., Ca). limb-scatter retrievals of aerosol extinction are insensitive to In our experiments, Sr isotopic fractionation is influenced external information about aerosol absorption. by both barite saturation state and temperature. However, neither dominantly controls Sr isotopic fractionation under our experimental conditions. Temperature dependent isotopic fractionation of Sr under our experimental conditions was very weak and negative (-0.0032 / C), however the variation of the isotopic data is largely within the analytical uncertainty of the measurement over the* +temperature range of our 88/86 experiments, 5 to 40 C. The relationship between ! Srbarite-aq

for all experiments and DSr was not significant, but was affected by the solution+ initial barite saturation state, which likely influences precipitation rate. At a constant intital barite saturation state, the relationship is significant and appears to be independent of temperature and (Sr/Ba) ratio.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2490 Goldschmidt2013 Conference Abstracts

Lithium isotope variation in rivers Prospective shale gas zones in the and lakes on the Tibetan Plateau Kimmeridgian and Tithonian strata U. WIECHERT1*, M. WEYNELL1, S. BARVENCIK1, of Polish Lowlands 2 AND J. A. SCHUESSLER 1 1 D. WI.C/AW * AND M.J. KOTARBA 1 Freie Universität Berlin; Germany (*correspondance: 1 AGH University of Science and Technology, Mickiewicza 30 [email protected]) St., 30-059 Kraków, Poland (*correspondence: 2GFZ German Research Centre for Geosciences, Helmholtz [email protected]) Centre Potsdam, Potsdam, Germany

Kimmeridgian strata in the Norwegian and North Seas are We report lithium abundances and isotope ratios for lakes, considered to be responsible for hydrocarbon generation of tributaries, and large rivers (Indus, Yarlung Tsangpo and large petroleum conventional accumulations [1]. Although Yellow River) on the Tibetan Plateau. In rivers we found exploration of these strata in Poland did not record solely calcium-bicarbonate waters, whereas lakes with commercial accumulation of petroleum, the preliminary sodium-chloride and sodium-sulfate waters could be studies [2] reveal generation of oil and gas in areas, where the distinguished. The chemical composition of the rivers Upper Jurassic strata were covered by thick Cretaceous rocks. primarily reflects weathering of rocks in carbonate-rich In the present study we determinate areas and depth intervals catchments. In contrast, lake water chemistry is affected by of possible shale gas accumulation in these strata. evaporation and crystallization of minerals. This is indicated Results and disscusion by a high level of mineralization and an electric conductivity A total of 482 core samples: 242 from the Kimmeridgian of more than 10 mS/cm, which classifies them as salt lakes. and 240 from the Tithonian strata from 40 wells of central part The !7Li of lake waters varies between +7.0 and +25 relative of Polish Lowlands were analysed. Rock-Eval pyrolysis to L-SVEC. The !7Li of rivers in the south range from +4.0 to reveals total organic carbon (TOC) contents from 0.14 to 9.6 +9.0 and the Yellow River in the NE gives a !7Li ~ +18. The wt% in the Kimmeridgian samples and from 0.19 to 12.5 wt% variation of !7Li in the water samples is, in general, consistent in the Tithonian samples. The highest values were recorded in with fractionation of isotopically light lithium in secondary the Upper Kimmeridgian and Lower Tithonian strata (TOC, clay minerals during weathering in the catchments [1,2]. up to 12.5 wt%, usually above 2 wt%). Rock-Eval, biomarker However, at the lake Tashi Namtso a systematic isotopic and kerogen elemental composition data evidence domination difference between inflow and lake provides evidence for of the oil-prone Type-II kerogen in this most prospective lithium isotope fractionation in the lake. In this example a sequences. Organic matter mostly is immature or early mature. strong pH change from about 8.2 to 9.8 is observed at the 1-D modelling of the petroleum generation processes [2] transition from river to lake waters. It is suggested that reveal that in selected deeply buried structures in the /ód0 formation of clay minerals at the transition cause an additional Trough, the Upper Jurassic source rocks reached maturities isotopic shift by ~10 ‰. In the large rivers of the southern corresponding to peak of oil window (0.7 - 1.0% Ro). Tibetan plateau low !7Li are consistent with a transport- Conclusion limited weathering regime, whereas the rather high !7Li of the Intense sampling and Rock-Eval analyses enabled authors Yellow River favour a weathering-limited transport regime. to designate a ca. 60 m thick marly shale complex at the The results support that riverine lithium isotopes are a border of Kimmeridgian and Tithonian strata in /1czyca–Ko2o powerful proxy for the intensity of silicate weathering in a area as the most prospective for shale gas exploration. catchment [3] rather than silicate weathering rates [4]. The study was financed by the Ministry of Science and However, in some areas lithium isotope compositions of the Higher Education (Projects Nos. N307 3141 39 and 744/N- tributaries are affected by sulfate-rich thermal waters. How IRAN/2010/0). much this alters the weathering budget of the large rivers is

difficult to estimate because evaporates and hot springs, which [1] Espitalie, Lafargue, Eggen (1991) Spec. Pub. of EAPG, 1, are important players in the terrestrial lithium cycle, are yet to 49-63. [2] Wi1c2aw, Kosakowski (2011) Goldschmidt be constrained. Conference, 2156.

[1] Huh et al. (1998) GCA 62, 2039-2051 [2] Vigier et al. (2009) GCA 72, 780-792 [3] Misra & Froehlich (2012) Sci. 335, 818-823 [4] Vigier et al. (2009) EPSL 287, 434-441.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2491

Tracing local industrial pollution Geochemical and isotopic sources with mercury isotopes investigation of fluids from JAN G. WIEDERHOLD1,2*, MARTIN JISKRA1,2, Lahendong geothermal field 3 3 4 ULF SKYLLBERG , ANDREAS DROTT , SOFI JONSSON , 1 2 1 4 2,5 B.A. WIEGAND *, M. BREHME , F. TEUKU , ERIK BJÖRN , BERNARD BOURDON 1 1 3 1 I.A. AMRAN , R. PRASETIO , Y. KAMAH AND RUBEN KRETZSCHMAR 1 AND M. SAUTER 1Soil Chemistry, IBP, ETH Zurich, Switzerland 1Univ. Göttingen, GZG, Goldschmidtstr. 3, 37077 Göttingen, (*correspondence: [email protected]) 2 Germany, ([email protected]) Isotope Geochemistry, IGP, ETH Zurich, Switzerland 2 Helmholtz Centre Potsdam – GFZ, Telegrafenberg, 14473 3Forest Ecology and Management, SLU Umeå, Sweden 4 Potsdam, Germany, ([email protected]) Chemistry, Umeå University, Sweden 3 Pertamina Geothermal Energy, Jl.M.H. Thamrin No.9, 5ENS Lyon and CNRS, France Jakarta 10340, Indonesia.

Stable mercury (Hg) isotope analysis offers a promising Lahendong geothermal field is a high-temperature liquid- tool for tracing sources of anthropogenic Hg pollution in the dominated system located in North Sulawesi (Indonesia) with environment. Mass-dependent (MDF) and mass-independent a current power production capacity of 80 MW (Operator: fractionation (MIF) of Hg isotopes results in two-dimensional Pertamina Geothermal Energy). The geology of the area isotope signatures of different Hg sources and can help comprises Late Pliocene to Mid-Pleistocene volcanic rocks of understand transformation processes at contaminated sites. Mount Tondano and younger eruptions, including basaltic and Here, we present Hg isotope data for sediments collected andesitic lavas and pyroclastics [1,2]. Deep reservoir fluids are in the vicinity of different industrial pollution sources in dominated by Cl-SO -HCO and Cl type, while HCO -rich and Sweden. The sampling sites covered a range of environmental 4 3 3 SO -HCO type fluids discharge at the surface [2]. conditions (salinity, organic matter, temperature) and were 4 3 We investigated trace elements and naturally occurring contaminated with either elemental Hg from the chlor-alkali isotope systems (D-O, Sr, Ca) in fluids from hot springs, industry or with phenyl-Hg used as preservative for pulp fibers shallow groundwater wells, geothermal production wells, and in the paper industry. In addition to analyzing total sediment surface waters from the Lahendong area to elucidate solute digests, a sequential extraction method designed to separate sources and geochemical processes in the aquifer. "D and sulfide- and non-sulfide-bound Hg was performed on selected "18O values of the fluid samples suggest a meteoric origin of samples. Stable Hg isotope ratios were measured by CV-MC- geothermal groundwaters. Variable trace element concen- ICPMS using standard-bracketing (NIST-3133) and Tl trations are subject to differences in weathering regime and addition for mass bias correction. geochemical equilibrium conditions in the aquifer. Deep The sediments exhibited a wide range of total Hg fluids are usually characterized by high As (- 4 mg/L), Cs (- concentrations from 0.8 to 229 %g g-1, consisting dominantly 1.4 mg/L), and Li (- 2.3 mg/L) and low Ca and Mg of organically-bound Hg(II) and a smaller pool of sulfide- concentrations (- 6 mg/L). In turn, surface waters and hot bound Hg. The Hg isotope ratios of the three phenyl-Hg sites 202 springs have higher Ca and Mg concentrations but are low in displayed nearly identical signatures (MDF " Hg: -0.2 to 87 86 As, Cs, and Li content (<0.5 mg/L). Sr/ Sr ratios are lower -0.5‰, MIF 3199Hg: -0.05 to -0.10‰). In contrast, the four in surface waters and hot springs (0.7039 – 0.7043), while sites which had been contaminated with elemental Hg showed 87 86 fluids of the deeper reservoir have higher Sr/ Sr ratios much greater variations ("202Hg: -2.1 to 0.6‰, 3199Hg: -0.19 (0.7050 – 0.7057), which suggests differences in the Sr to 0.03‰), but with distinct ranges for the different sites. isotope composition of andesitic and basaltic rocks in the The sequential extraction data revealed that the smaller 44/40 reservoir and at the surface. " Ca values vary between -1.50 sulfide-bound Hg pool was in some samples up to 1‰ heavier and 0.09 ‰ and may be employed as an indicator for in "202Hg than the dominant organically-bound Hg pool. The processes involving dissolved Ca2+. These processes include selectivity of the sequential extraction procedure was assessed dissolution of minerals, cation exchange, and precipitation of using standard materials prepared with enriched stable Hg secondary Ca-bearing phases. isotope tracers, which also allowed to gain insight into the

exchange of Hg isotopes between different Hg pools. [1] Koestono et al. (2010) Proceedings World Geothermal Our results suggest that different industrial pollution Congress 2010; Bali, Indonesia. [2] Utami et al. (2007) sources can be distinguished based on their Hg isotope Proceedings 29th NZ Geothermal Workshop 2007. signatures, which can additionally record fractionation processes between different Hg pools in the sediments.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2492 Goldschmidt2013 Conference Abstracts

Source and speciation of 14C in a Irradiation histories of meteoritic cement-based repository for inclusions measured by 40K radioactive waste D. WIELANDT1 AND M. BIZZARRO1 E. WIELAND1*, J. SCHENZEL1 AND G. SCHLOTTERBECK2 1Centre for Star and Planet Formation, University of 1 Copenhagen, Denmark ([email protected]). Paul Scherrer Institute, Laboratory for Waste Management,

5232 Villigen PSI, Switzerland (*correspondence: The solar and galactic cosmic rays recorded by chondrules [email protected]) and refractory inclusions (CAIs and AOAs) can provide 2University of Applied Sciences Northwestern Switzerland, unique information on their formation, transport and storage School of Life Sciences, 4132 Muttenz, Switzerland histories. To explore the irradiation histories of these objects,

we have developed novel analytical protocols to accurately Carbon-14 is an important contributor to the annual dose measure Ca/K ratios and K-isotopes by thermal ionization released from a cement-based repository for low- and mass spectrometry [1]. The low abundance of 40K relative to intermediate-level radioactive waste in Switzerland. To date, 39K makes the 40K/39K ratio a sensitive indicator of spallation, performance assessment has to be based on assumptions whereby efficient spallogenic production of 40K occurs regarding the speciation and mobility of 14C bearing through proton irradiation of calcium targets by 43Ca(p,()40K compounds. It is considered that 14C mainly contributes to and 44Ca(p,n+()40K. Because proton stopping and reaction dose in its organic form, such as 14C bearing organic depths at relevant energies are similar to the sizes of the compounds, which are only weakly retarded in the inclusions, 40K depth profiles can allow us to discriminate cementitious near field. between solar and galactic cosmic rays. Further, the common Compilations of the activity inventories reveal that, in the K retains information on precursor irradiation. already existing and future arising of radioactive waste in We selected well characterized CAIs and AOAs from Switzerland, the 14C inventory is mainly associated with Efremovka carbonaceous chondrite (CV3red) and chondrules activated steel (! 85 %). The inventories of activated steel from the NWA 5697 ordinary chondrite (LL3). The three and 14C in the repository are well known. However, the chondrules selected for study have variable U-corrected Pb-Pb chemical speciation of 14C in the cementitious near field upon dates and 54Cr compositions [2], suggesting lateral transport release from activated steel is only poorly investigated. and storage of these objects in the solar protoplanetary disk for Identification and quantification of the 14C bearing organic at least ~2 Myr prior to their accretion in the NWA 5697 compounds formed during the anoxic corrosion of activated parent body. All material analyzed show large (i.e. permil to steel is a major challenge, firstly due to the low 14C inventory percent) positive 40K anomalies that broadly correlate with of the material available for the corrosion experiment, and Ca/K ratios, consistent with spallation of Ca. The 40K secondly due to the extremely low corrosion rate of steel in anomalies in the 3 chondrules vary with their absolute Pb-Pb alkaline solution (few nm/year). Thus, the development of an dates, such that the oldest chondrules register the largest analytical method with a very low 14C detection limit is doses. At face value, this is consistent with a monotonic required, such as compound-specific 14C AMS. As a first step irradiation source, suggesting that 40K anomalies were towards the development of the technique, batch-type generated during storage in the protoplanetary disk, likely corrosion experiments with non-activated, carbon-containing from exposures to galactic cosmic rays. The comparable iron powders were carried out with the aim of identifying dosages recorded by CAIs and chondrules suggest a similar potentially 14C bearing organic compounds. The powders were transport mechanism, possibly associated with stellar outflows immersed in groundwater- and cement-type solutions and [3]. Similarly to CAIs, we infer that some chondrules formed time-dependent changes in the concentrations of dissolved and in the inner regions of the protoplanetary disk were ejected to gaseous carbon species were determined using high- large orbital distances and drifted back to the accretion regions performance ion exclusion chromatography coupled to of chondrites over timescales of a few Myr. We are currently conductivity detection and mass spectrometry and gas conducting 40K depth profiles of large, well characterised and chromatography coupled to mass spectrometry. The Pb-Pb dated chondrules to test this conclusion. conceptual approach for a corrosion study with activated steel

along with first results will be discussed. [1] Wielandt & Bizzarro (2011) JAAS 26, 366 [2] Connelly et al. (2012) Science 338, 651 [3] Shu et al. (1996) Science 271, 1545

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2493

Sieve textures in impact zircon from Modeling nanomaterial transport and Vredefort, South Africa: Implications biouptake in a complex aquatic to impact geochronology system: Exploring surface affinity as MATTHEW M. WIELICKI* AND T. MARK HARRISON1 a predictor of nanoparticle fate 1Department of Earth and Space Sciences, University of MARK WIESNER1,2, MATHIEU THEREZEIN1,2, California, Los Angeles, 595 Charles E. Young Drive FABIENNE SCHWAB1,2, LAUREN BARTON1,2, East, Los Angeles, CA 90095 CHRISTINE HENDREN1,2, GREGORY V. LOWRY3,2, (*correspondence: [email protected]) RAJU BADIREDDY1,2, BENJAMIN ESPINASSE1,2, BENJAMIN P. COLMAN1,2, EMILY S. BERNHARDT1,2, The bombardment history of our planet has major JEAN-YVES BOTTERO4,2AND MELANIE AUFFAN4,2 implications for Earth’s atmosphere, habitability, near surface 1Duke University, Durham, NC 27708 conditions, and the delivery of the building blocks of life over 2Center for Environmental Implications of Nanotechnology its four and a half billion years. Constraining the impact flux 3 Carnegie Mellon University, Pittsburgh, PA 15213 to the Earth-Moon system was highlighted by the National 4Centre de Recherche et d’Enseignement de Géosciences de Research Council's 2007 report "The Scientific Context for the l’Environnement, Aix-en-Provence, France Exploration of the Moon" as the top priority goal for lunar research. Evidence of the early impact flux has largely been A recent study of silver nanoparticles introduced to a based on interpretations of 40Ar-39Ar ages of lunar samples simulated freshwater wetland indicated an initial period of which can be problematic due to the presence of relic clasts, particle removal and associated die-off of some aquatic plants. incomplete Ar outgassing, diffusive modification during shock This talk considers the initial transport and fate of and heating, and exposure to solar wind and cosmic rays [1]. nanoparticles introduced to this system from the standpoint of Recent studies [2,3] have utilized zircon from Apollo samples heteroaggregation, deposition, and dissolution and the as well as lunar meteorites to better constrain the impact implications for short-term impacts on rooted aquatic plants. history of the Moon. Sieve textures found in zircon within Simulations show that nanoparticles introduced in a complex, lunar meteorite SaU 169 have been identified as "poikilitic albeit greatly simplified environment exhibit a wide range of impact melt zircon formed during equilibrium crystallization behaviors depending on their affinities for each other and their of the impact melt" and used to better constain the age of the concentrations. The complexity of these interactions appears Ibrium impact [3]. Such textures had previously not been to be governed by the relative affinity of nanoparticles for observed in terrestrial zircon. We report the first terrestrial each other (autoaggregation) and with background particles sieve textures in zircon isolated from Vredefort impactites. (heteroaggregation) and other native surfaces. Surface affinity Zircons isolated from the granophyre unit show a intimate as a predictor or nanoparticle fate is explored further in the relationship with pyroxene, similar to that seen in the lunar context of interactions with plant surfaces biofilms and the samples, most likely due to resorption. U-Pb analysis of such potential for uptake by plants. A functional assay for grains clearly shows that the zircons have been inherited from determining the affinity of nanoparticles for complex mixtures the target and are not neo-formed zircon that crystallized from of native particles is evaluated. the impact melt and thus should not be used to imply impact

events. Pb-loss is highly variable in these samples and the lower intercept age of ~1985±150 Ma agrees well with that of the Vredefort impact [4,5]. Zircon geochronology offers a new tool with which to constrain planetary impact histories however effects on zircon from impact events remain poorly understood and need to be explored terrestrially prior to making interpretations on extraterrestrial samples.

[1] Fernandes et al. (2013) MAPS 48, 241-269. [2] Nemchin et al. (2008) GCA 72, 668-689. [3] Liu et al. (2013) EPSL 319-320, 277-286. [4] Kamo et al. (1996) EPSL 144, 369- 387. [5] Wielicki et al. (2012) EPSL 321-322, 20-31

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2494 Goldschmidt2013 Conference Abstracts

The end-Permian mass extinction and Experimental study of majorite its aftermath stability in chromium rich garnets 1 1 1 PAUL B. WIGNALL CH WIJBRANS *, S KLEMME AND A ROHRBACH School of Earth and Environment, University of Leeds, UK 1Institut für Mineralogie, Universität Münster, Germany, ([email protected]) (*[email protected])

Our understanding of the timing of the end-Permian mass Garnet is an important constituent of upper mantle rocks, extinction an subsequent recovery has improved dramatically and is stable over a wide range of pressures. At high in the past few years. For long thought to be a protracted affair pressures(>5GPa), silica is incorporated into the octahedral spread over several million years of the Late Permian, by the site in the garnet structure partially replacing aluminium, 1990s it was re-evaluated as a geologically abrupt crisis. which results in the so-called majorite component. In mantle Latest work shows the marine (and probably the terrestrial) rocks, this will cause the pyroxenes to gradually dissolve into extinction to be a two-phased event that straddles the Permian- garnet with increasing pressure [1]. Majoritic garnets are Triassic boundary whilst the record from higher northern sometimes found as inclusions in deep diamonds and in (Boreal) latitudes suggests the extinction phase was somewhat mantle peridotites. The silicon content of these garnets is often earlier. The ~200 kyr interval between the extinction pulses used to estimate the depth of origin of these samples [2]. saw a transient recovery of the benthic fauna. The significance In addition to pressure [1], majorite stability is also of this improved resolution of extinction timings can be expected to depend on temperature, composition of the garnet compared with recent advances in both our understanding of and presence of other Al-bearing phases or melt. For instance, ocean redox and sea-surface temperatures at this time. The the presence of chromium or ferric iron may decrease majorite first pulse of extinction saw the onset of open ocean anoxia stability with increasing pressure. If true, this has implications but only a transient pulse of low- oxygen conditions whilst the for the interpretation of the formation depth of diamond second extinction pulse, in the earliest Triassic, coincides with inclusions as the Cr/(Cr+Al) ratio is much higher in depleted the long-term establishment of global marine anoxia. The lithospheric mantle compared to fertile mantle. contemporaneous oxygen isotope record of conodont To investigate this further, we performed high pressure phosphate reveals a rapid temperature rise that persisted long high temperature experiments in a Walker-type multi anvil in to the Early Triassic. press (Bristol design) at pressures between 6 and 14 GPa, and The Early Triassic fossil and geochemical record is one of temperatures between 1400 and 1700 °C. Starting materials the most extraordinary of the Phanerozoic. Carbon isotope consist of silicate glasses or oxide mixes in the system Cr2O3- stratigraphy is highly unstable with a series of both positive CaO-MgO-Al2O3-SiO2, with varying Cr2O3/(Al2O3+Cr2O3) and negative excursions whilst the oxygen isotope record ratio. Major and minor element concentrations of the phases shows similar instability reflecting major temperature present were determined by electron microprobe. oscillations within an overall exceptionally hot interval. This All experiments yielded garnet, most contained opx, culminated in the latest Smithian Stage with very light "13C olivine and (minor) cpx as stable phases. At high temperatures values (~2‰) and "18O values suggestive of equatorial sea- only one pyroxene phase is stable. Preliminary results indicate surface temperatures >40oC. The marine invertebrate record is that for constant pressures and temperatures, the majorite remarkbaly impoverished for 2 myrs with little in the way of component in garnet decreases with increasing Cr/(Cr+Al) of recovery of the benthos whilst nektonic organisms radiated the bulk composition. However, this effect is most notable at with their usual exuberance. Only after the Late Smithian high pressures (>11GPa), at lower pressures this effect is Thermal Maximum can it be claimed that widespread smaller. diversification is underway although not until the Middle Triassic are conditions truly normal in marine and terrestrial [1] Akaogi and Akimoto (1977) Physics of the Earth and habitats. Planetary Interiors 15, 90-106. [2] Griffin (2008), Geology 36, 95-96.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2495

Power stations as a source of Delamination of the North China atmospheric particulate matter in Craton: A widespread phenomenon southern Poland or a one-off situation? W. WILCZY(SKA-MICHALIK1*, R. MORYL1, B. SUDER1, S.A. WILDE AND M. MICHALIK2 Dept. of Applied Geology, Curtin University, Perth, Australia 1Pedagogical University, ul. Podchor45ych 2, Kraków, Poland (*correspondence: [email protected]), The North China Craton is widely recognized as the type- ([email protected]; [email protected]) example of delamination of an Archean craton and, although it 2Jagiellonian University, ul. Oleandry 2a, Kraków, Poland has been extensively investigated over the past decade, many ([email protected]) and diverse reasons have been suggested to explain the phenomenon; but with little consensus reached. Although High concentration of atmospheric particulate matter in several surface features and the Mesozoic rock record indicate southern Poland is a problem of great meaning. The it was operative in the Cretaceous, outstanding issues include: improvement of this situation needs the recognition of the when did delamination/thinning commence; what were the source of aerosol particles (natural or anthropogenic; local mechanisms involved; was there a link to marginal orogenic source or long distance transport). Power stations are belts; was paleo-Pacific plate subduction a controlling factor; considered to be an important source of atmospheric pollution and did global tectonic processes play a role? A review of in Poland. Changes in fuel used (coal, coal+biomass, biomass) geological data from the Archean to the present-day indicates and in combustion technology caused much bigger variability a number of unique features in the North China Craton that in the composition and morphology of fly ash particles than it most likely contributed to its ‘decratonization’ in the was noted in the past when pulverized coal boilers were Mesozoic [1]. However, were these sufficient to make it a mainly used. Interpretation of origin of aerosol particles is also one-off situation or was this process more widespread in the more difficult. geological past? This has important implications with respect Fly ash from coal fired pulverized bed and fluidized bed to the preservation of ancient continental crust and thus for boilers is similar in chemical composition but mineral models of continental growth. Tomographic studies indicate composition differs (less mullite and glass in ash from that other cratonic areas also have thinned lithosphere, but it is fluidized bed boiler but more coaly irregular particles) as well uncertain if this, on its own, will ultimately lead to their as morphology of particles. Fly ash from coal and biomass co- destruction. Since the thickness of the lithosphere exherts an

combustion in pulverized bed boiler is rich in SiO2, Al2O3, important control on the deformation of continental blocks

Fe2O3, MgO and CaO. Beside quartz, mullite, glass, Fe when they get dismembered and re-distributed in oxides, Ca, Ca-Mg or Ca-Mg-Fe oxides are present. supercontinent cycles, it is important to identify features that Aluminosilicate spheres (<1 µm - 50 µm) are accompanied by may have resulted from earlier delamination or thinning. numerous, usually porous and less regular spheres Ca or Ca- Likewise, the fact that certain areas currently involved in Mg, Ca-Mg-Fe oxides. Fly-ash from fluidized bed boiler fired collisional events, such as Tibet and Iran, have thickened

with biomass is rich in SiO2 (content of CaO is low; Al2O3 lithospheres with seismic properties that resemble cratonic very low). Bigger particles are composed of quartz core with areas [2], indicates that ‘cratons’ may develop by several reaction rim or of glass, smaller (<1 mm - 10 mm) are different mechanisms, perhaps with diagnostic characteristics. represented by glassy spheres or irregular fragments of glassy Evidence from the North China Craton will be reviewed with particles. respect to the various models proposed to explain Study was supported by NCN grant No. delamination/thinning, with the aim of resolving some of the 579/B/P01/2011/40. contentious issues and leading toward a consensus.

[1] Yang et al. (2008), Geology 36, 467-470; [2] McKenzie & Priestley (2008), Lithos 102, 1-11.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2496 Goldschmidt2013 Conference Abstracts

Mobility of inorganic and organic Orogenic Eclogites, Rutile and Trace compounds from black shales during Element Flux in the Subduction Zone unconventional gas production DARREN J. WILKINSON*, GODFREY FITTON, 1,2 1 AND SIMON L. HARLEY F.D.H. WILKE *, A. VIETH-HILLEBRAND , R. NAUMANN1, B. HORSFIELD1 AND J. ERZINGER1,2 Grant Institute, The King’s Buildings, West Mains Road, 1 Edinburgh (*correspondance: [email protected]) GFZ German Research Centre for Geosciences,

Telegrafenberg, 14473 Potsdam, Germany 2 The geochemical evolution of the continental crust, University of Potsdam, Department of Earth and oceanic crust and mantle is strongly influenced by complex Environmental Sciences, Karl-Liebknecht Str. 24-25, geochemical processes occurring in the subduction zone. 14467 Potsdam, Germany (*[email protected]) However, significant gaps exist in our understanding of these controls on the behaviour of important trace elements. Using Taking into account the envisaged activities of shale gas orogenic eclogites from the Western Gneiss Region (WGR) of exploitation and production from black shales in central Norway as analogues for subducted oceanic crust, we Europe we see an increasing demand in a quantitative quantitatively assess the behaviour of many of these elements. evaluation of possible environmental risks and impacts. For Rare Earth Element (REE) and immobile High Field the development of a shale gas play, water is mixed with Strength Element (HFSE) compositions have shown that most proppant material (e.g. sand grains) and 0.5 – 1% of additives. Norwegian eclogites have E-MORB to N-MORB protoliths. Additives, such as acids, biocides, corrosion inhibitors and Using elements thought to be highly immobile (e.g. Nb, Hf), friction reducers are used to optimize the fracturing job. we have estimated the likely total element flux for many more Besides of flow-back water a varying amounts of mobile trace elements. production water will appear at the surface containing various We also assess the role of accessory rutile in controlling salt compounds, gases, heavy metals, radioactive elements and HFSE flux from the slab. Nb/Ta as well as Zr/Hf ratios in organics. In order to investigate the mobility of Ca, Fe, S and rutile vary from sub- to superchondritic, yet mean grain trace elements such as Co, Cr, Cu, Mn, Mo, Ni, Pb, U, V, Zn compositions appear essentially chondritic (19.9, 34.5 and selected organic compounds during hydrofracturing we respectively). Whole rock samples reflect this variance on a performed sequential leaching tests with 12 black shales from much larger regional scale, since average ratios for eclogites five locations in Europe and the US. Using five different across the whole WGR are also chondritic. We discuss artificial fracking fluids 24h short-term experiments were possible explanations and consequences for heterogeneity in carried out at ambient pressure and temperatures of up to these processes. 100°C. Two long-term experiments lasting, respectively, 6 and

3 months, respectively, at 100°C / 100bar were performed

with selected black shales from Bornholm, Denmark and Lower Saxony, Germany, using a fracking fluid with additives provided by the industry. We characterized the black shales by XRD, XRF and ICP-

MS following HF-HClO4 dissolution before and after the experiments. Fluids were analysed by ICP-MS, IC, LC-OCD and Gas MS and GC. The amount of dissolved constituents after the experiment is independent from the pH of the fracking fluid but highly dependent from the element content in the black shale and the buffering capacity of specific components, namely pyrite and carbonates. Shales containing carbonates buffer the solution at pH 7-8. Sulphide minerals (pyrite) become oxidized and

generate sulfuric acid (H2SO4) leading to a pH of 2-3. Shales containing pyrite but only traces of, or lacking, carbonates give rise to low pH fluids responsible for the much higher concentrations of most dissolved cations (except e.g. Mo, Sr). In each experiment, less than 15% of a certain element contained in the black shale was mobilised into the fluid.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2497

The & 182W isotope composition of the Archean Mo isotopic evolution: ca. 3920 Ma Acasta Gneiss Complex Comparing the Pilbara and the M. WILLBOLD1,3, S. J. MOJZSIS2 AND T. ELLIOTT3 Kapvaal Cratons 1Imperial College London, Earth Science and Engineering, M. WILLE1, F.KURZWEIL1, S. EROGLU1 London, SW7 2AZ, United Kingdom; R. SCHOENBERG1, N. BEUKES ([email protected]) AND M. VAN KRANENDONK3 2University of Colorado, Geological Sciences, Boulder, 1Dept. of Geoscience, University of Tuebingen,Wilhelmstr. Colorado 80309-0399, USA; [email protected] 3 56, 72074 Tuebingen, Germany University of Bristol, School of Earth Sciences, Bristol, BS1 2 University of Johannesburg, Auckland Park Kingsway 8RJ, United Kingdom; ([email protected]) Campus, 2006, South Africa 3 School of Biological, Earth and Environmental Sciences, The short-lived 182Hf-182W decay system (t ca. 9 Myr) is 1/2 University of New South Wales, Kensington, NSW 2052, a useful tracer to investigate accretionary and geodynamic Australia processes on the early Earth. Variable enrichments in

182W/184W – expressed in the conventional &182W notation – The environmental and geochemical circumstances which have been documented in Eoarchean crustal rocks. These data led to heavy Mo isotopic signatures in Archaean sediments were interpreted by invoking either a ‘Late Veneer’ model [1], remains elusive. Sufficiently oxidising conditions, which or via early Earth differentiation processes_ENREF_2 [2]. enable mobility of Mo in its highest oxidation state, are Here we report the first &182W measurements for rocks from generally seen as one precondition for the formation of such the Acasta Gneiss Complex (AGC), a terrane located on the an isotopically heavy Mo seawater reservoir. However, western margin of the Slave craton in the Northwest interpretation of temporal changes in Mo isotopic Territories (Canada). The AGC is the oldest known crustal compositions stored within ancient sediments is often domain with primary magmatic ages that are about 3,920 Ma hampered by the fact that they are strongly influenced by [3]. It is also apparent that these rocks inherited a much older paleo-environmental conditions during sediment formation. (ca. 4,200 Ma) crustal component [4]. Our samples include As such, sedimentary Mo isotopic signatures different to that granitoid gneisses and plagioclase-hornblende schists that of the continental crust are often only qualitative rather than define a range in &182W values comparable to those found in quantitative indicators of changes in environmental redox rocks from the ca. 3,800 Ma Isua Supracrustal Belt in southern conditions. West Greenland, which formed the basis of the ‘Late Veneer’ Here we present Mo stable isotope datasets, published and model presented in [1]. Using these new values for the AGC new data, from different 3.46 to 2.5 Ga old sedimentary in conjunction with previous data, we test the two models for environments from the Pilbara (Australia) and Kapvaal (South the W isotopic evolution of bulk silicate Earth in the terminal Africa) Cratons, respectively. Mo isotopic results for 62.76 Ga Hadean. Our results provide new motivation in the search for old sedimentary rocks are within the field of continentally other daughter products of extinct nuclides (e.g. 142Nd) in the derived detritus, indicating insufficient O levels required to AGC. 2 oxidize and mobilize this element. In contrast, Mo isotopic

signatures in sediments -2.7 Ga are isotopically heavier than [1] Willbold, M. et al. Nature 477, 195-198 (2011); [2] sedimentary material solely continent derived. Comparing the Touboul, M. et al. Science 335, 1065-1069 (2012); [3] Cates, Pilbara and the Transvaal general trend to heavier Mo isotopic N.L. et al. (in review); [4] Iizuka, T. et al. Geology 34, 245- values in Mo isotopic evolution can be seen in both basins 248 (2006). approaching 2.5Ga. These heavier Mo isotopic signatures, in conjunction with the apparent elevated concentrations of other redox sensitive elements, such as U and Re, after 2.7 Ga suggests aquatic mobilization of these elements under

sufficient O2 levels. The comparison of Mo isotopic variations in different contemporary environmental sedimentary setting allows us to ascertain the reasons for the observed Mo isotopic fluctuations.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2498 Goldschmidt2013 Conference Abstracts

Temporal evolution of detrital Temporal Variability of Coastal cosmogenic denudation rates in Rainwater Fe(II) Concentration and transient landscapes from in situ- Wet Deposition to Surface Seawater 10 produced and meteoric Be J.D. WILLEY, B.C. RICE, J.J. HUMPHREYS, R.J. KIEBER,

1 2 J.R. HELMS, G.B. AVERY AND R.N. MEAD J.K. WILLENBRING *; N. M. GASPARINI , B.T. CROSBY3, G. BROCARD1, M.E. OCCHI1 1University of North Carolina Wilmington, Department of AND P. BELMONT4 Chemistry and Biochemistry, Wilmington, NC USA 1 28403-5932 (*correspondence: [email protected]) Department of Earth and Environmental Sciences, University

of Pennsylvania, Philadelphia, PA, USA 2 The concentration and stability of dissolved Fe(II) in Department of Earth and Environmental Sciences, Tulane rainwater collected in Wilmington, North Carolina, USA, have University, New Orleans, Louisiana, USA decreased by more than an order of magnitude in the 3Department of Geosciences, Idaho State University, preceding decade. Rainwater Fe(II) during the winter of 2003 Pocatello, Idaho, USA, 4 was stable for more than 96 hours, whereas in 2011, Department of Watershed Sciences, Utah State University, concentrations decreased by 60% within 4 hours. A decade Logan, Utah, USA, (*[email protected]) ago, rainwater Fe(II) was strongly complexed by organic

10 ligands which stabilized it against oxidation. Currently Fe(II) In equilibrium landscapes, Be concentrations within appears to be present in rainwater predominantly as detrital quartz grains are expected to quantitatively reflect photochemically produced inorganic Fe2+(aq). Spectral slope basin-wide denudation rates. In transient landscapes, though data indicates rainwater dissolved organic carbon (DOC) has detrital quartz is derived from both the incising, adjusting become less conjugated and smaller in average molecular lowland and the unadjusted, relict upland, the integrated 10Be weight, consistent with less iron complexation. These changes concentrations still provide a denudation rate averaged across in DOC may result from improved control of automobile the two domains. Because field samples using in situ- emissions. Inorganic Fe2+(aq) can be rapidly oxidized by H O produced 10Be can only provide a snapshot of the current 2 2 and, in rains with pH > 5 (half of all rains), by O . H O has upstream-averaged erosion rate, we employ a numerical 2 2 2 10 doubled in the last decade due to lower emissions of SO (a landscape evolution model to explore how Be derived 2 sink for H O ), which increases the oxidation rate of Fe2+(aq) denudation rates vary over time and space during long-term 2 2 by approximately 30%. transient adjustment. Model results suggest that the A decade ago, rainwater was a source of soluble Fe(II) to longitudinal pattern of mean erosion rates is generated by the surface seawater, where it is a phytoplankton nutrient. river’s progressive dilution of low-volume, high-concentration Because of the decreased concentration and stability of Fe(II) detritus from relict uplands by the integration of high-volume, in rain, Wilmington NC rainwater is now a much smaller low-concentration detritus from adjusting lowlands. The source of soluble Fe(II) to North Atlantic surface seawater, proportion of these materials in any detrital sample depends on which may reduce primary productivity and hence lower CO what fraction of the upstream area remains unadjusted. 2 uptake in this region. On shorter timescales, a single storm can induce transience in a landscape. Meteoric 10Be concentrations can be measured in submilligram-sized sediment samples and this attribute enables us to measure suspended sediment through a hydrograph. The meteoric 10Be concentration in river sediment changes with the source areas and fluxes of material supplied to the stream. The average concentration from the couplet of the rising and falling limbs of the hydrograph can differ from the concentration of the sediment that is preserved in depo- centers. Using this short timescale system, we reconsider how to interpret paleoerosion rates from depo-centers derived from meteoric and in situ-produced 10Be concentrations.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2499

Iron isotope fingerprinting of mantle Analysing conodont " 18O by SIMS mineralogy I.S. WILLIAMS1, J.T. TROTTER2, M. RIGO3 4 1 2 AND C.R. BARNES HELEN M. WILLIAMS AND MICHAEL BIZIMIS 1 1 Research School of Earth Sciences, Australian National Dept. Earth Sciences, Durham University, Durham, DH1 University, Canberra! [email protected]) 3LE, UK; ([email protected]) 2 2 School of Earth and Environment, University of Western Dept. Earth and Ocean Sciences, University of South Australia, Perth:(( [email protected] ) Carolina, Columbia, SC 29208; ([email protected]) 3Department of Geosciences, University of Padova, Padova:

([email protected]) Mineralogical and lithological variations in the Earth’s 4School of Earth and Ocean Sciences, University of Victoria, mantle have important implications for mantle dynamics, (Victoria: [email protected]) magma generation, and the fate of recycled surface material. Directly tracing such variations is challenging. While the elemental and radiogenic isotope compositions of mid oceanic Oxygen isotope compositions of phosphatic conodont ridge and ocean island basalts (MORB and OIB respectively) microfossils are a more robust indicator of early Paleozoic sea are thought to reflect variable amounts of enriched surface temperatures than the O compositions of calcitic mineralogies within the mantle, in the form of pyroxenite or brachiopods. SIMS microanalysis allows conodont O eclogite derived from oceanic crust or metasomatised compositions to be determined on an ~30 µm scale, so the lithosphere, directly linking geochemical and mineralogical isotopic homogeneity of individual conodont elements and of variation is difficult. Iron (Fe) stable isotopes potentially offer multiple elements from a single rock sample can be assessed. a solution to this problem, as the Fe isotope compositions Analyses can be obtained on very small and/or rare specimens, ("57Fe) of mafic rocks primarily reflect mineral-specific and targeted on those parts of conodonts that are best partitioning [1, 2]. Here we present Fe isotope data for sub- preserved. Differences in composition between co-existing oceanic lithosphere peridotite and pyroxenite xenoliths from species from different biofacies can be measured. SIMS Oahu, Hawaii and demonstrate that Fe isotopes can be used as analyses, however, are less precise and more sensitive to a new tracer of mantle mineralogical heterogeneity. differences in the chemical composition of the sample than Pyroxenite "57Fe values are heavy (0.10 to 0.27‰) relative to conventional IRMS analyses. The latter is important because MORB and OIB ("57Fe ~ 0.15‰) [3-6] and reflect isotopic the conodont crown can consist of two tissue types: albid— fractionation during magmatic differentiation and pyroxene large (>100 µm) crystals containing mostly PO4, and cumulate formation at the lithosphere-asthenosphere hyaline—microcrystals with PO4 and some CO3, and a higher boundary. In contrast, peridotites have light "57Fe values (– trace element content. Some conodonts also contain poorly 0.34 to 0.14‰) that correlate with elemental and radiogenic mineralised basal tissue that can be isotopically contaminated. isotope tracers of melt extraction, providing evidence for Fe In addition, conodont crystal structure can be modified at isotope fractionation during partial melt extraction and the temperatures above ~100˚C. No conodont sample is available generation of depleted, low- "57Fe peridotitic residues. The that is both isotopically uniform and abundant enough to be heavy "57Fe values of MORB and OIB relative to mantle distributed between SIMS and IRMS labs as an O isotope peridotites can therefore be explained by partial melting, standard. SIMS measurements are currently referenced to a where isotopically heavy Fe is preferentially concentrated in mineral apatite standard (Durango 3 at ANU), and potential the melt phase. However, the considerable range in MORB systematic bias is assessed by comparing SIMS and IRMS and OIB "57Fe requires a "57Fe -heterogeneous mantle, analyses of large bioapatite samples (e.g. shark enameloid), containing enriched (pyroxenite, heavy "57Fe) and depleted and of conodonts from the same or closely equivalent rock peridotite (light "57Fe) domains. Iron stable isotopes thus samples. As part of our study of sea surface temperatures at provide a powerful new means of fingerprinting mineralogical critical periods of biotic crisis and environmental change in variations within the Earth’s mantle and identifying depleted the Paleozoic and Early Mesozoic using conodont O isotopes, and enriched components within the source regions of we have addressed issues of bias, inter- and intra-conodont volcanic rocks. heterogeneity, and thermal alteration (as indicated by Colour Alteration Index). In some samples we find O variation within [1] Weyer & Ionov EPSL (2007); [2] Williams et al. EPSL and between elements, but more commonly there is inter- and (2005); [3] Dauphas et al. EPSL (2009); [4] Teng, et al. intra conodont uniformity between genera and species in a Science (2008) [5] Weyer et al. EPSL (2005); [6] Teng et al. single rock sample within the sub-permil precision of the GCA (2013). measurements. The rare exceptions have both biological and geological explanations.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2500 Goldschmidt2013 Conference Abstracts

Linking fluvial processes and Petrologic implications of magmatic elemental cycling within the underplating: Observations from the Old Rifle, CO aquifer Athabasca granulite terrane K.H. WILLIAMS1*, M.J. ROBBINS1, S.B. YABUSAKI2 AND M.L. WILLIAMS1*, S.J. SEAMAN1 AND G.C. KOTEAS2 1 P.E. LONG 1 Dept. of Geosciences, Univ. of Masschusetts, Amherst, Ma 1Earth Sciences Division, Lawrence Berkeley National 01003 (*correspondence: [email protected]) Laboratory, Berkeley, CA 94720, USA, (*correspondence: 2Dept. of Geology, Norwich Univ., Norwich VT ([email protected])(, [email protected],) ([email protected]) The Chipman mafic dike swarm, Athabasca granulite 2Pacific Northwest National Laboratory, Richland, WA 99352, terrane, Saskatchewan, CA, provides a field example of mafic USA ([email protected]) magmatic intraplating in the deep continental crust. The Chipman dikes were emplaced at 1.0-1.2 GPa (35-40 km) at A successive series of biostimulation experiments within 1.9 Ga, possibly above a magmatic underplate. The dikes are the Old Rifle, CO (USA) aquifer since 2002 have focused on dominated by Hbl and Pla with minor Cpx. Host rocks include biogeochemical pathways arising from organic carbon the 3Ga Chipman tonalite and 2.6Ga Fehr and Stevenson injection and its role in mediating the cycling of iron, granites. Several effects of underplating have been manganese, sulfur, uranium, vanadium, arsenic, and selenium. documented, including tonalite genesis, granite genesis and While most have concentrated on reductive pathways and their contamination, garnet growth, and crustal densification. Only impact on contaminant mobility, recent studies have begun to limited melting was induced in the Chipman tonalite during explore oxidative pathways and their impact on metals underplating and intraplating. Instead, the mafic dikes dynamics, carbon modification, and the long-term viability of themselves were partially melted to Grt + tonalite. reductive immobilization as a remedial strategy. Insights Leucosomes occur in strain shadows associated with garnet. gained from such experiments have shed light on analogous Where melting was extensive, individual leucosomes have natural biogeochemical pathways that mediate element cycling coalesced and tonalite dikes and veins are common. Within in the absence of exogenous carbon amendment. Within the the Fehr granite/gneiss, partial melting was extensive. aquifer, such pathways are often seasonal and correlate with Leucosome veins, pods, and pools apparently represent the excursions in groundwater elevation of 1-2m associated with products of several melting reactions, including hydrous increased discharge in the Colorado River during modal melting and both biotite and hornblende dehydration spring/summer snowmelt. Imbibition of oxygen bubbles melting. Granitic partial melt apparently accumulated in an within the capillary fringe associated with such excursions is early (S1) foliation and then was mobilized during formation inferred to be the primary contributor to seasonally oxic of a “megacrenulation” into S2. This “pumping” mechanism groundwater, with its impact on redox-mediated reactions provides one model for melt segregation in the deep crust. exhibiting close correspondence to intentional introduction of Subsequent Chipman dikes mingled and mixed with the new oxidants. granitic magma producing a wide range of hybrid Superimposed upon natural and artificial redox compositions. With increasing extent of granite melting, fluctuations are relic signatures of the depositional fabric of Chipman dikes are more irregular in geometry, apparently alluvial accumulation. Specifically, ferromanganese-encrusted trapped by the granite mush. Magmas moving to higher levels cobbles accumulated as channel fill deposits serve as an probably evolve from mafic to contaminated intermediate and effective vector for iron and manganese delivery during felsic compositions over time. Other granitoids in the region incipient accretion of the aquifer materials. Post-depositional were apparently heated and deformed but not melted during redox processes and oxygen incursion associated with dike emplacement and underplating. One common reaction groundwater level fluctuations enable redistribution and involves Opx + Pla = Grt + Cpx. Extensive Grt production mineralization of iron and manganese throughout the aquifer, leads to increased density, up to 3.0 g/cm3 even in felsic rocks with subsequent implications for carbon and metals and may play a role in stabilization and possibly delamination transformations. Linking such pathways within the context of of lower continental crust. Based on the Athabasca example, a ‘porous subsurface bioreactor’ constitues an ambitious yet underplating can initiate a number of positive and negative tractable means for quantifying elemental fluxes at the feedbacks that ultimately result in dramatic and probably floodplain and potentially larger scales. irreversible changes in character, rheology, composition of the overlying crust.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2501

Rare Earth Element ore genesis: LA-ICPMS2: Laser ablation sampling The Great Unknown with combined ICP-Q-MS and MC- ANHONY E. WILLIAMS-JONES1 ICP-MS detection for simultaneous 1Earth and Planetary Sciences, McGill University, Montreal, trace elemental and isotope ration Canada, ([email protected]) analyses

1 1 Economic or potentially economic REE deposits are JULIAN D. WILLS , NICHOLAS LLOYD , LOTHAR 1 1 hosted by or genetically associated with alkaline igneous rocks ROTTMANN , CLAUDIA BOUMAN 2 and carbonatites. Primary REE enrichment in silicate magmas AND STEVE SHUTTLEWORTH depends on the highly incompatible nature of the REE, may be 1Thermo Fisher Scientific, Hanna-Kunath-Strasse 11, 28199 facilitated by fluoride complexation, and occurs at late stages Bremen, Germany, ([email protected]) of magma evolution through crystal settling and crystallisation 2Photon Machines Inc, USA of residual, fluid-saturated liquids including immiscible fluoride melts. Carbonatite magmas likely owe their REE In situ analysis by laser ablation offers significant enrichment to the high solubility of the REE, and their advantages to users in a range of applications including preference for the LREE to the similar ionic radii of Ca2+ and 3+ geochronology but interrogating the sample for all of the Ce ; HREE are smaller. information required may not be possible in a single Hydrothermal mobilisation may be essential to the measurement. Laser ablation is a destructive sampling economic viability of many REE deposits. Indeed, the World’s technique and while many samples are large enough to allow largest deposit, Bayan Obo, China, is dominantly for multiple analyses on a range of instruments, hydrothermal. Although aqueous fluoride complexes are geochronologically relevant samples are often so small as to widely thought to be the main agent of REE transport, preclude multiple analyses. These samples are often unique modelling of natural systems suggests that this is not the case. and once sampled by laser ablation, they are lost and no Instead, chloride complexes appear to be responsible for REE further information can be extracted. transport. Moreover, experiments suggest that REE chloride In this presentation, a system for the simultaneous isotopic complexes can cause the observed preferential LREE and elemental characterization of zircon (ZrSiO4) is mobility. Hydrothermal concentration of REE occurs when described. A high performance 193nm excimer laser (Photon interaction of acid REE-Cl-bearing fluids with pH-buffering Machines Analyte G2) is used to sample ~50 µm diameter pits rocks, or mixing with neutral fluids, and/or decreasing in the zircon, and the He carrier gas containing the entrained temperature, induces REE mineral deposition. sample is split between ICP-Q-MS and MC-ICP-MS systems. A new high performance ICP-Q-MS system (Thermo Scientific iCAP Q) is used for the quantification of trace elements (both transition metals and rare earth elements) and MC-ICP-MS (Thermo Scientific Neptune Plus) is used for high precision Pb and Hf isotope ratio measurements. The advantages afforded by such combined, simultaneous isotopic and elemental analyses of growth zones of minerals will be highlighted in the presentation

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2502 Goldschmidt2013 Conference Abstracts

Deep ocean circulation and its link to Co-precipitation of arsenate with carbon storage through glacial cycles calcite – an example from Greece D.J. WILSON1,2*, A.M. PIOTROWSKI2, A. GALY2 AND LENNY H.E. WINKEL1,2, BARBARA CASENTINI3, V.K. BANAKAR3 FABRIZIO BARDELLI4, ANDREAS VOEGELIN1, NIKOLAOS 5 4 1 P. NIKOLAIDIS AND LAURENT CHARLET Department of Earth Science and Engineering, Imperial College London, London, SW7 2AZ 1Eawag: Swiss Federal Institute of Aquatic Science and (*correspondence: [email protected]) Technology, Ueberlandstrasse 133, P.O. Box 611, 8600 2 Department of Earth Sciences, University of Cambridge, Duebendorf, Switzerland, [email protected], Cambridge, CB2 3EQ [email protected] 3 National Institute of Oceanography, Dona Paula, Goa, 403 2Swiss Federal Institute of Technology (ETH) Zurich, 8092 004, India Zurich, Switzerland, [email protected] 3Water Research Institute-National Research Council, Via Storage of carbon in the deep ocean during glaciation and Salaria, 00015 Monterotondo (RM), Italy, its release during deglaciation is widely called upon in order to [email protected] 4 explain glacial-interglacial changes in atmospheric CO2 [1,2], Université Joseph Fourier, Grenoble, 1381 rue de la Piscine, but the mechanisms involved remain uncertain and the 38400 Saint-Martin d’Hères, France, locations of carbon storage are poorly quantified through time. [email protected], [email protected] Changes in water mass volumes in the global ocean exert one 5Technical University of Crete, Polytechnioupolis, 73100 first order control on carbon storage [3], suggesting a Chania, Greece, [email protected]

sensitivity of atmospheric CO2 to reorganisations of ocean circulation. However, modelling studies tend to disagree over The uptake of arsenic (As) in calcite may represent an the nature and timing of paleoceanographic changes important immobilization process for As in calcareous rocks.

influencing atmospheric CO2 [4,5]. Nevertheless, knowledge on this retention mechanism in the Better paleoceanographic constraints are therefore natural environment is limited since As incorporation in required, particularly from the deep Indo-Pacific, which has calcite has mostly been studied on synthetic samples. significant potential for carbon storage during glacial periods. We identified very high levels of As (up to 913 mg/kg) in Here we characterise its chemical evolution over the last 250 travertine deposits derived from geothermal As-enriched

thousand years using Nd isotopes (&Nd) and benthic carbon groundwaters on the Greek peninsula Chalkidiki.. We isotopes ("13C) in deep Indian Ocean core SK129-CR2 [6]. analyzed two different types of travertine from this region

The &Nd record indicates a significant glacial reduction in the using both bulk and micro-focused X-ray absorption North Atlantic Deep Water component in Circumpolar Deep spectroscopy (XAS and µ-XAS) and micro-focused X-ray Water, consistent with increased oceanic carbon storage [3]. fluorescence spectroscopy (µ-XRF) to determine the 13 1 However, the &Nd-" C relationship evolves over the course of mechanism of arsenic uptake in the travertines . Bulk XAS each glacial cycle, indicating a changing global distribution of showed that in all of the studied samples As is present as water masses and carbon. During glaciation and early glacial arsenate (As[V]), and µ-XRF analyses revealed that As is 13 periods, &Nd and " C are decoupled, revealing carbon cycling closely associated with the calcite matrix. Iron on the other changes that are independent of Atlantic circulation changes. hand was found to be mainly present as a constituent of clay This decoupling may reflect the processes involved in carbon minerals, of presumably detrital origin, suggesting that Fe- sequestration in Antarctic Bottom Water at these times. In (hydr)oxides were not sufficiently abundant to act as major 13 contrast, coupled &Nd-" C changes during late glacials and scavengers for As in the Chalkidiki travertines. deglaciation suggest a close link between deep ocean From our results we estimate that the natural travertines circulation and carbon release to the atmosphere. could sequester at least 25% of groundwater As(V) via co- precipitation with calcite. The formation of As-enriched [1] Toggweiler, Russell & Carson (2006), Paleoceanography calcite is thus an efficient mechanism to immobilize As in the 21. [2] Sigman, Hain & Haug (2010), Nature 466, 47-55. [3] geothermal groundwaters of Chalkidiki and could possibly Skinner (2009), Clim. Past 5, 537-550. [4] Brovkin et al. also occur in other environments characterized by high As and (2007) Paleoceanography 22 [5] Hain, Sigman & Haug CO2 contents. (2010) Glob. Biogeochem. Cycle 24. [6] Piotrowski et al. (2009) Earth Planet. Sci. Lett. 285, 179-189 [1] L.H.E. Winkel; B. Casentini; F. Bardelli; A.Voegelin; N.P. Nikolaidis; L. Charlet. Geochim. Cosmochim. Acta 2013, 106 99–110.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2503

Role of climatic factors on the Reconstruction of humid phases in terrestrial distribution of selenium the Caribbean during the Late LENNY H.E. WINKEL1,2, BAS VRIENS1, TIM BLAZINA1, Pleistocene 1 1 RITA SCHUBERT , AND C. ANNETTE JOHNSON 1, 2 1 SOPHIE WINTERHALDER * , DENIS SCHOLZ , 11Eawag: Swiss Federal Institute of Aquatic Science and AUGUSTO MANGINI2, CHRISTOPH SPÖTL3, THOMAS E. Technology, 8600 Duebendorf, Switzerland, MILLER4, AMOS WINTER5, KLAUS PETER JOCHUM6 (*correspondence: [email protected]), AND JESÚS M. PAJÓN7 [email protected], [email protected], 1 Institute for Geosciences, University of Mainz, J.-J.-Becher- [email protected], [email protected] Weg 21, 55128 Mainz, Germany, (*correspondence: 2Swiss Federal Institute of Technology (ETH) Zurich, 8092 [email protected]) Zurich, Switzerland, [email protected] 2 Institute of Environmental Physics, University of Heidelberg,

INF 229, 69120 Heidelberg, Germany, Selenium (Se) is of key importance for human health . 3Institute of Geology and Palaeontology, University of However, due to the highly uneven global distribution of Innsbruck, Innrain 52, 6020 Innsbruck selenium in agricultural soils, it is estimated that 0.5 to 1 4 Department of Geology, University of Puerto Rico, billion people have too low Se intake. As a result Se Mayagüez, PR 00681 supplementation and fortification of foods are being 5 Department of Marine Sciences, University of Puerto Rico, increasingly discussed as possible strategies for improving Mayagüez, PR 00681 human Se status. Despite observations that the Se distribution 6Max Planck Institute for Chemistry, Hahn-Meitner-Weg 1, in the natural environment is closely related to human health 55128 Mainz, Germany issues and our growing awareness of the importance of this 7 National Museum of Natural History, Department of element, the behavior of Se in the natural environment is still Paleogeography and Paleobiology, La Habana, Cuba poorly understood. It is therefore of major importance to better

understand the factors that control this distribution. For the Caribbean, high-resolution terrestrial records are The atmosphere is an important transient reservoir for Se, mainly available for the Holocene and suggest a linkage to which is largely fed by volatile Se compounds formed via North Atlantic climate variability (e.g. [1]). During the Late biomethylation in marine and terrestrial environments. In turn, Pleistocene climate in the North Atlantic area was also subject the atmosphere can also function as a source of terrestrial Se to large and rapid changes, which are evident in climate when it is returned to the Earth’s surface via wet and dry records from Central America as well [2]. We present precise deposition. In this talk we will give new insights into the 230 MC-ICP-MS Th/U-dating, together with stable isotope and processes that are relevant to the atmospheric Se reservoir. We trace element data from three speleothems from Puerto Rico will also present new evidence on how climatic conditions and Cuba, which grew between 80 and 7 ka BP. Growth play a major role in the large-scale terrestrial Se distribution, phases of Caribbean speleothems are assumed to reflect humid both directly as a source of Se (via atmospheric deposition) phases in the tropical Atlantic. Stalagmite ENS2 from Puerto and indirectly by controlling pedoclimatic regimes and thus Se Rico grew in several phases (63-61, 40-39, 34-31 and 17- bioavailability. Therefore, it can be expected that changes in 13 ka BP), coinciding with periods of weak East Asian climatic conditions will have a significant impact on the Se Summer Monsoon recorded in speleothems from China [3]. A distribution in the environment. We will show how climatic large stalagmite from Puerto Rico (Larga1) reveals a variable factors can be used to predict large-scale terrestrial Se growth rate between 35 and 17 ka BP. Stalagmite CM from distribution. This will be crucial in helping to understand and Cuba grew, interrupted by a few short-term hiatuses, between prevent future health hazards resulting from the uneven 80 and 7 ka BP. High-resolution multi-proxy (stable isotope distribution of Se in the environment. and trace element) records from these speleothems are currently in preparation. They will deliver a deeper understanding of climate variability during the Late Pleistocene in the tropical Atlantic region and identify potential teleconnections to the North Atlantic.

[1] Hodell et al. (2008). QSR. 27, 1152-1165. [2] Fensterer et al. (2012). The Holocene 22, 1405-1412. [3] Wang et al. (2001). Science 294, 2345-2348.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2504 Goldschmidt2013 Conference Abstracts

H in garnet: Implications for upper Comparison of LDI and ESI to study mantle H2O storage capacity natural organic matter on the ANTHONY C WITHERS AND MARC M HIRSCHMANN molecular level by FT-ICR mass Dept of Earth Sciences, University of Minnesota, MN, USA spectrometry 1 M. WITT The maximum amount of H2O that can be stored in mantle minerals without saturation to stabilise a fluid or melt (the 1Bruker Daltonik GmbH, Bremen, Germany

H2O storage capacity) varies as a function of pressure, temperature and peridotite phase assemblage. The systematics FT-ICR mass spectrometry of NOM

of H2O storage capacity in olivine and pyroxene are relatively Fourier Transform ion cyclotron resonance (FT-ICR) mass

well established. The H2O storage capacity of nominally spectrometry (MS) is a well known method to study natural anhydrous garnet, on the other hand, is poorly understood. organic matter (NOM) on the molecular level. Mainly Measurements of H in pyropes synthesised in hydrothermal electrospray ionization in negative ion mode is used to detect experiments at 1000 °C suggest that the hydrogarnet compounds in this complex mixture. However, also component becomes destabilised at pressures greater than 7 Laser/desoption ionization (LDI) in negative ion mode can be GPa [1], suggesting that under conditions approaching those used to study NOM. LDI has been used recently to analyze of the transition zone, where garnet makes up an appreciable crude oil by FT-ICR mass spectrometry [1]. LDI has the proportion of the mantle, garnet does not contribute advantage to be independent of the solvent. Several NOM

significantly to the mantle H2O storage capacity. Annealing of standards have been analyzed by ESI and LDI for comparison natural pyrope under similar conditions of P and T, however, of both ionization techniques. Additionally the effect of suggest that other types of H defect may result in pyrope collison energy and laser power has been studied.

storage capacities approaching 200 ppm H2O at 10 GPa [2]. In

contrast, H contents in excess of 1000 ppm H2O were measured in natural, Fe-bearing pyropic garnet that was hydrothermally annealed in the presence of olivine at 1100 °C

at pressures up to 9 GPa [3]. If such elevated H2O storage

capacities are applicable to mantle garnet, H2O fluxed melting of the upper mantle overlying the transition zone would

require bulk H2O concentrations in excess of 600 ppm [4]. We have examined the systematics of H incorporation in pyrope in 24h hydrothermal experiments at 2-8 GPa and 1400 °C. Platinum capsules were loaded with 2 compositional layers such that the upper part of the capsule contained pure pyrope (py) composition and the remainder a mixture of Figure 1: Van Krevelen plots of ESI- and LDI-FT-ICR MS

forserite (fo), enstatite (en) + 5 wt.% Al2O3. Buffering of SiO2 measurement of Suwannee river fulvic acid activity by growth of fo and en during experiments was verified by Raman spectroscopy. Grain growth in the py Discussion and results composition layer was facilitated by lack of grain boundary Calculations of the molecular formulas of detected pinning. FTIR spectra of 100-700 %m pyropes from compounds were based on exact mass measurements using experiments at 4, 6 and 8 GPa all display a characteristic ultra-high resolution and high mass accuracy of FT-ICR mass hydrogarnet absorption band. Our preliminary results suggest spectrometry. Lower H/C as well as O/C ratios have been

that H content is close to 235±75 ppm H2O over this pressure observed in LDI than ESI. This effect is shown in the Van range. At mantle temperatures, it is unlikely that garnet is a Krevelen plots of Suwannee river fulvic acid in Figure 1.

major contributor to bulk mantle H2O storage capacity. Therefore, highly aromatic compounds are ionized using LDI at UV-wavelength of 355 nm. [1] Withers et al (1998), Chem Geol 147, 161-171. [2] Lu and Collision induced fragmentation results mainly in a loss of Keppler (1997), Contrib. Mineral. Petrol. 129, 35-42. [3] CO2. However, experiments with high laser power results only Mookhergee and Karato (2010), Geophys. Res. Lett. 37, in a loss of water. L03310. [4] Tenner et al (2012), Contrib Mineral. Petrol. 163, 297-316. [1] Cho et al. (2012) Anal. Chem. 84, 8587-8594.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2505

Determination and comparison of Spectroscopic studies of radionuclide acidic gas ratios at the Stromboli adsorption and diffusion Volcano and Mount Etna obtained by R.A. WOGELIUS1*, A. VAN VEELEN 1, B. ZOU1, various active alkaline traps J.R. BARGAR2, G.E. BROWN JR.2,3, G. LAW4 AND G.W. GRIME5 1 ,2 2 3,4 J. WITTMER * , N. BOBROWSKI , M. LIOTTA , 1 4 5 2 Williamson Research Centre, SEAES, Oxford Road, G. GIUFFRIDA , S. CALABRESE AND U.PLATT University of Manchester, Manchester M13 9PL, UK 1University of Bayreuth, Atmospheric Chemistry Research (*correspondence:[email protected]) Laboratory, Bayreuth, Germany (*Julian.Wittmer@uni- 2Stanford Synchrotron Radiation Lightsource, PO Box 4349, bayreuth.de) Stanford, California 94309, USA 2University of Heidelberg, Institute of Environmental Physics, 3School of Earth Sciences, Stanford University, Stanford, Heidelberg, Germany California 94305-2115,USA 3 4 Second University of Naples, Dip. DiSTABiF, Caserta, Italy Centre for Radiochemistry Research, School of Chemistry, 4 Istituto Nazionale di Geofisica e Vulcanologia, Palermo, Italy University of Manchester, Manchester M13 9PL, UK 5 University of Palermo, Dip. CFTA, Palermo, Italy 5Ion Beam Centre, Advanced Technology Institute, University of Surrey, Guildford GU2 7XH, UK Determining volcanic gas composition by direct plume sampling is still challenge in volcanic research. At most Solute mobility in geochemical fluids depends strongly on volcanoes (e.g. Stromboli volcano, Italy) scientists have to both the physical properties of the host lithology as well as deal with difficult access to the plume, strong atmospheric mineral surface reactivity. Due to the extremely slow rates of dilution and varying weather conditions making a high diffusion and the typically dilute concentrations of sampling performance necessary. radionuclides involved in disposal scenarios, constraining Besides a more accurate quantification of the main acidic physical and chemical processes for use in risk models is gas compounds (CO2, SO2, H2S, HCl) a reduction of detection challenging. Therefore predictions about the mass transfer of limits for less abundant species (HF, HBr, HI) were achieved contaminants over time periods pertinent to geological in this work. For this purpose a Raschig-Tube [1] was disposal facilities (105 to 106 years) require both reliable modified and utilized for the application on volcanic plumes. measurements of adsorption and robust determinations of The theoretical and experimental absorption properties of the diffusive flux. Here we will present results from spectroscopic Raschig-Tube (RT) and the Drechsel bottle (DB) [2] set-ups measurements designed to provide chemical details of the were characterized and afterwards applied simultaneously to process of surface attachment of key radionuclides (U, Tc, Sr, the well-established Filter packs technqiue (FP) in the field Cs) to a number of mineral surfaces (magnesite, brucite, (on Stromboli and Mount Etna). The obtained results make a portlandite, magnetite, phyllosilicate, K-feldspar, plagioclase comparison between the set-ups possible and help to point out feldspar) that will be exposed under a range of repository the potential weakness and strength of each set-up. conditions (pH 6-13, reducing and oxidizing conditions, low Additionally, the analytical procedure, including sample and high PCO2). EXAFS, both standard and polarization preparation, analysis by Titration, Ion Chromatography and dependent, has been used to provide unambiguous information Inductively Coupled Plasma Mass Spectrometry, was regarding surface adsorbate bonding geometries. Evolution of optimised to accurately quantify molar concentrations of surface morphology and details of thin films or surface dissolved compounds. precipatates has been studied using x-ray reflectivity and The progress in sampling and analysis led to a significant glancing incidence XRD. Bulk adsorption experiments have data set that covers most of the important elements. In also been completed in order to meaasure mass uptake as a particular, less abundant species were quantified more function of concentration. In addition, diffusion through low accurately due to the RT technqiue. Therefore, even iodine permeability rock matrices (which include the minerals used could be detected at Stromboli. Besides difficulties to in the adsorption studies) has been directly determined via determine fluorine and carbonate, influences of saturation both flow-through (micro-reactor) and in situ (Multiple effects on the FP results could be observed and characterized. internal reflection-FTIR) experimentation. Direct measurements of contaminant uptake and diffusion length [1] Levin et al. (1980) Radiocarbon 22, 379-391. [2] Liotta have been completed using proton induced x-ray emission et al. (2012) Geochem. Geophys. Geosyst., 13 (5) (PIXE) coupled with Rutherford Back-Scattering (RBS).

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2506 Goldschmidt2013 Conference Abstracts

Formation and metamorphism of the Surface topography controls on Upper Sulfide Zone of the Salt River calcite growth kinetics: From VMS deposit (South Africa) Molecular Dynamics simulations to CORA C. WOHLGEMUTH-UEBERWASSER1,2, macroscopic-scale modelling 1 1 FANUS VILJOEN AND CRAIG R. MCCLUNG 1,2 1 MARIËTTE WOLTHERS, * DEVIS DI TOMMASO, ZHIMEI 1Paleoproterozoic Mineralization Group (PPM), Department DU1 AND NORA H DE LEEUW1,2 of Mineralogy, University of Johannesburg, South Africa; 1 Department of Chemistry, University College London, 20 ([email protected]) Gordon Street, London WC1 H0AJ, U.K. (* 2PetroTectonics Centre, Department of Geological Sciences, Correspondence: [email protected]) Stockholm University, Sweden 2 Department of Earth Sciences-Geochemistry, Utrecht

University, P.O. Box 80021, 3508 TA Utrecht, the Sulfides from the upper sulfide zone of the Salt River Netherlands. VMS (South Africa) were analyzed for PGE (platinum group elements), Re, Au, Sb, As, Se, Te, Cr, Co, Ni, Mn, Mo, Ag, Cation dehydration is generally accepted to be the rate- Hg and Pb using in-situ LA-ICP-MS (laser ablation- limiting step to ionic crystal growth from aqueous solution. inductively coupled plasma-mass spectrometry) techniques. Our classical Molecular Dynamics simulations show a The analysis of a plethora of trace elements during the variation in water exchange frequency at structurally distinct ablation of one single spot was possible by using a multi calcium sites in the calcite surface of about two orders of standard approach, involving the analysis of several external magnitude. A process-based calcite growth kinetics model has standards before, after and between the analysis of unknowns. been re-parameterized, using the water exchange frequencies Chondrite normalized PGE patterns best fit data from Besshi- computed from our molecular dynamics simulations, to type deposits, implying the formation within a back-arc basin represent the attachment frequencies of carbonate and environment. bicarbonate ions. This calcite growth kinetics model illustrates the impact of variations in attachment frequencies on kink- formation frequency (Figure 1), step velocities and bulk growth rate. The calculated frequencies of kink formation show a strong variation with surface structures, which can be amplified further depending on the saturation state and calcium-to-carbonate ratio in the aqueous solution. Modelled and measured step velocities and bulk growth rates are generally in agreement, showing that surface topography might at least partially induce variations in calcite growth rates and step velocities as observed experimentally.

This conlusion can be drawn although the Salt River VMS deposit experienced peak amphibolite metamorphism as metamorphism of the deposit was isochemical with respect to the PGE and Au.

Figure 1: Variation in kink formation frequency with surface topography.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2507

Trace elements in Catanda Mass-(in)dependent Cd isotope carbonatitic massif (SW Angola) fractionation during evaporation WOLKOWICZ STANIS/AW* BOJAKOWSKA IZABELA, FRANK WOMBACHER1 AND MARK REHKÄMPER2 WOLKOWICZ KRYSTYNA, AND SMAKOWSKI TADEUSZ 1 Institut für Geologie und Mineralogie, Universität zu Köln, PGI-NRI, 4 Rakowiecka, 00-975 Warsaw, Poland 50674 Köln, Germany, ([email protected]) ([email protected]) 2 Dept. of Earth Science & Engineering, Imperial College, London SW7 2AZ, UK. The Catanda carbonatite massif (SW Angola) is built mainly of lapilli and lapilli-ash tuffs, ash tuffs, carbonatites Here, we investigate large mass-dependent (MDF) and and granulated carbonatites. very small mass-independent fractionations (MIF) of Cd The studies covered 43 samples of rocks of the massif. isotopes that result from the evaporation of liquid Cd into Concentrations of Sc, Y, Li, Ta, Zr, Nb, Th, As, Ba, Co, Cr, vacuum at 10-4 mbar and ~180°C [1]. Cu, Ga, Hf, Mo, Ni, Pb, Rb, Sr, U, V, Zn and REE were Cadmium stable isotope data were obtained using a determined by the ICP-MS and ICP-OES methods after Neptune MC-ICP-MS. To resolve small mass-independent dissolving the rocks in aqua regia. anomalies, residual Cd metal samples were analysed at high Concentrations of radioactive elements are rather low. U ion beam intensities typically >20V for 114Cd and long concentrations range from 1 to 20 ppm. Mean levels in tuffs analysis times (30 min.). (8.6 ppm) is higher than in lavas (5.9 ppm). Th contents range MDF in the residual Cd metal samples from vacuum from 5 to 52 ppm. Mean levels of Th tend to be higher in lavas evaporation experiments are well described by Rayleigh (30.4 ppm) than in tuffs (28.8 ppm). Nb concentrations range distillation with a vapor-residue fractionation factor ( = from 14 to 652 ppm, with mean levels equal 383 ppm for tuffs 0.9900 for 114Cd/110Cd (i.e. 10.0‰) [1]. The observed and 285 ppm for lavas. Li contents range from 9 to 55 ppm, fractionation is much less than predicted from kinetic theory 110 114 0.5 attaining 21 ppm at the average. Cr concentrations range from ((kin = (mass Cd / mass Cd) = 0.9823; i.e. 17.7‰), a 25 to 161 ppm, being markedly higher in tuffs (49 ppm) than mismatch that is frequently observed, e.g. [2]. in lavas (33 ppm). Cu contents range from 11 to 356 ppm, The accurate quantification of mass-independent being much lower in tuffs than in lavas (29 and 48 ppm at the fractionation (MIF) in residual Cd metals required that the average, respectively). V concentrations range from 33 to 222 large mass-dependent fractionation is accurately corrected. ppm (98 ppm at the average). Zn contents change from 57 to This is facilitated using the generalized power law and 551 (124 ppm at the average). Ba concentrations change from normalization to 110Cd/114Cd of the starting material [1]. After 250 to 1700 ppm (950 ppm at the average). Sr contents change correction, deficits ranging from 8 to 28 ppm were well from 0,08 to 0,54%, with mean levels clearly higher in resolved for 111Cd/114Cd, 113Cd/114Cd and 116Cd/114Cd. The carbonatite lavas (0.21%) than in tuffs (0.16%). observed pattern is in accord with predictions from nuclear Concentrations of Ga, Hf, Ni, Pb, As and Co are low and charge radii and thus indicate nuclear volume effects [3-6]. poorly differentiated as they appear generally unrelated to The preferential evaporation of 111Cd, 113Cd and 116Cd may petrology. The rocks are also enriched in REE, especially result from their more tightly bound 5s electrons and hence LREE (La, Ce, Pr and Nd). Sum REE contents range from weaker metallic bonds in the liquid as previously suggested 0.25 to 0.95%. The concentrations were found to be markedly for Hg [7,8], another group 12 element. The observation of higher in tuffs (avg. 0.33%) than in carbonatite lavas (0.21%). nuclear volume effects thus suggests that (metallic) bonding in Carbonatite lavas of the Catanda Massif are characterized the melt results in reduced fractionation factors. by higher mean levels of Cu, Zr, Th and HREE and the tuffs – by higher mean levels of Cr, U, V, Rb, Mo, Zn, Nb, Li and [1] Wombacher et al. (2004) GCA 68, 2349–2357. [2] Richter LREE. In turn, concentrations of As, Ba, Ga, Hf, Ni, Pb, Y et al. (2009) Chem. Geol. 258, 92–103. [3] Bigeleisen (1996) and Sc appeared not related to the types of rocks of that J. Am. Chem. Soc. 118, 3676-3680. [4] Schauble (2007) GCA massif. 71, 2170-2189. [5] Fujii et al. (2009) Chem. Geol. 267, 157- 163. [6] Rehkämper et al. (2011) Handbook Environ. Isotope Geochem., Chap. 8, 125-154. [7] Estrade et al. (2009) GCA 73, 2693–2711. [8] Ghosh et al. (2013) Chem. Geol. 336, 5- 12.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2508 Goldschmidt2013 Conference Abstracts

Melts, fluids, crystals, sulphides, Temporal evolution of the Raahe- metals: Trace element partitioning Ladoga Shear Complex, Finland: and geochemical applications Constraints from a sheared granitoid BERNARD J. WOOD in the Pielavesi Shear Zone Department of Earth Sciences, University of Oxford, U.K. J.WOODARD1*, P. TUISKU1, A. KÄRKI1 AND H. HUHMA2 ([email protected]) 1Department of Geosciences, University of Oulu, FI-90014

Oulu, Finland (*[email protected]) First there was Goldschmidt [1], then there was lattice- 2 Geological Survey of Finland, P.O. Box 96, FI-02151 Espoo, strain [2], so what else is there to learn about partitioning Finland behaviour? The answer is that we are now getting to the point where the geochemical problems are really interesting. Here The Fennoscandian Shield experienced several stages of are the things I will talk about: brittle - ductile deformation during the Palaeoproterozoic. The Olivine-liquid partitioning and basalt genesis: Ni Raahe Ladoga Shear Complex (RLSC) is a ~100 km wide, partitioning was completely understood long ago [3]. Ni NW - SE striking set of strongly sheared rocks and intervening contents of Hawaiian olivines hence seemed to require a crustal blocks in which antecedent structures are preserved. pyroxenitic mantle source. New experimental olivine-melt These were formed by long-term and multi-phase partitioning data indicate however that they can be explained Svecofennian convergent tectonic evolution and consist of by relatively high temperature of melting of “standard” supracrustal paragneisses and intrusive rocks. The latter are mantle. mostly pre- or syn-kinematic granitoids, but distinctly Chalcophile elements in terrestrial and martian basalts: postkinematic granite veins occur in all areas. The Pielavesi Chalcophile partitioning between sulphide melt and silicate Shear Zone (PSZ) in Central Finland is an important shear melt is a simple function of the FeO content of the silicate dominated, N-S striking unit within the RLSC. melt. This means we can quantify the influence of residual At Heinäsuo, in the Pielavesi parish, Central Finland, pre- sulphide on chalcophiles in terrestrial and martian melts. to syn-kinematic quartz diorite intrudes the PSZ. The quartz Residual sulphide appears to be critical to basalt generation on diorite has strong N-S foliation, likely developed during or Mars. immediately after crystallisation. This intrusion is cut by a Crystal-fluid partitioning of trace elements: Although late-kinematic, broadly N-S striking blastomylonite. U-(Th)- crystal-fluid partitioning is difficult to systematize, Pb geochronology of zircon, monazite and titanite are used to applications of the lattice strain approach show that place constraints on the timing of deformation and shearing hydrothermal minerals record the compositions of the fluids within the PSZ. Samples were collected from both the quartz from which they were generated when corrections for fluid diorite intrusion and the blastomylonite. Zircons were speciation are applied. separated from the quartz diorite using standard gravitational The “melt-effect” and trace element partitioning: It is now separation methods, while polished chips of the possible to measure trace element activities in silicate melts blastomylonite were selected for in situ analysis of monazite. using partitioning into metal as a monitor. The data are These were mounted in epoxy resin and analysed at the applicable to determination of melt composition effects on NORDSIM laboratory, Swedish Museum of Natural History, crystal-melt partitioning and other important properties such Stockholm, Sweden. Titanite was analysed in situ from as volatility. polished thin sections of quartz diorite using LA-ICP-MS at Metal-silicate partitioning and planetary core formation: the Geological Survey of Finland, Espoo, Finland. We are just getting to grips with the high pressures of core Zircons have oscillatory zoning patterns in BSE images, formation on Earth and the effects of the light element in the characteristic of igneous zircon. Analysis of the zircons core on partitioning between core and mantle. For Si, O and S resulted in a concordia age of 1884 +/- 6 Ma, providing a these effects are large for many trace elements. magmatic age and constraining an age maximum for

deformation in the PSZ. The monazite from the blastomylonite [1] Goldschmidt, V. M. Geochemistry. 730 pp (Clarendon has a concordia age of 1793 +/- 3, placing the brittle - ductile Press, 1954). [2] Blundy, J. D. & Wood, B. J. Nature 372, shearing event at ~100 m.y. later. The titanite age, 1780 +/- 23 452-454 (1994). [3] Hart, S.R. & Davis, K.E. Earth Planet. Ma, also indicates some recrystallisation in the quartz diorite Sci. Lett. 40, 203-219 (1978) during the late stage shearing event.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2509

The U-Pb in speleothem Some solid solutions involving Fe4O5 chronometer: Current progress and A.B. WOODLAND1, K. SCHOLLENBRUCH2, M. KOCH3, future prospects AND D.J. FROST4 1 1 1 Inst. Für Geowissenschaften, Universität Frankfurt, 60438 JON WOODHEAD * AND ROBYN PICKERING Frankfurt, Germany 1 School of Earth Sciences, The University of Melbourne, 2Deutsche Gemmologische Gesellschaft, 55743 Idar- Melbourne, VIC 3010, Australia Oberstein, Germany 3Inst. für Geowissenschaften, Universität, Heidelberg, 69120 The chronology of speleothems by the U-Pb method has Heidelberg, Germany reached the point of a robust analytical methodology with 4 Bayerisches Geoinstitut, Universität Bayreuth, 95440 enormous, but as yet largely unexploited, potential. A number Bayreuth, Germany of applications are beginning to appear relating to climate

change, tectonics and human evolution. The next decade will The recently discovered Fe-oxide phase with Fe4O5 likely see a major expansion of these activities. When coupled stoichiometry [1] opens up the potential for this phase being with other emerging technologies, the U-Pb chronology of stable in Earth’s mantle. This is particularly the case since [2]

speleothems from selected sites now has the potential to demonstrated that magnetite breaks down to Fe4O5 + Fe2O3 at provide novel insights (both palaeotemperature and 9-10 GPa over a large range of temperature. Thus it is palaeohumidity) into ancient climate—effectively ‘ancient important to know if this new phase can incorporate other weather stations’—from around the globe and throughout cations and form solid solutions which would expand its much of Earth history. Meanwhile studies of included pollens stability field in terms of P and T and composition. and microscopic animals offer insights into floral/faunal Experiments have been performed in 3 simple systems: i)

diversity and change through geological time. The Fe3O4-Fe2SiO4, ii) Fe3O4-(Mg,Fe)2SiO4, and iii) Fe3O4-

ramifications of these many developments will be significant FeCr2O4 over a P-T range of 9-16 GPa and 1100-1300°C.

across diverse fields of research, from human evolution, The Fe4O5 phase essentially excludes Si, even when it 3+ palaeontology and ecosystem development, through studies of coexists with stishovite or a Fe -bearing Fe2SiO4-rich spinel. weathering and erosion, to the influence of tectonics on The addition of Mg stabilizes a variety of assemblages in

landscape evolution. which the Fe4O5 phase occurs together with olivine, High-P clinopyroxene, spinelloid V, wadsleyite or ringwoodite. Experiments so far indicate solid solution of up to at least 25

mol % Mg2Fe2O5 component. Molar volumes decrease from 53.76 to 53.55 cm3 mol-1 over this solid solution range. Mg- 2+ Fe partitioning is such that the Fe4O5 phase is the phase phase/Fe4O5 richest in Fe in a given assemblage, with Kd usually

<0.14. Cr can also be incorporated in the Fe4O5 structure in 3+ exchange for Fe . In the bulk compositions studied, the Fe4O5 phase coexists with a spinel and/or a hematite-eskolaite solid solution. Up to 0.92 cats. Cr p.f.u. have been measured so far,

implying a Fe2Cr2O5 component of 46 mol %. Molar volumes

also decrease with increasing Fe2Cr2O5 content.

[1] Lavina et al. (2011) PNAS, 108, 17281-17285. [2] Woodland et al. (2012) Amer Mineral, 97,1808-1811.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2510 Goldschmidt2013 Conference Abstracts

Lead isotope analysis: Removal of Increasing spatial resolution of 204Hg isobaric interference from 204Pb lipid biomarker analysis by for U/Pb dating using an (MS/MS LDI FT-ICRMS capable) ICP-QQQ-MS L. WÖRMER1*, M. ELVERT1, J. FUCHSER2, J.S. LIPP1 AND 1 1 A 2 K.-U. HINRICHS GLENN WOODS AND JEAN-PIERRE LENER 1MARUM and Department of Geosciences, University of 1Agilent Technologies (UK) Ltd. 5500 Lakeside, Cheadle Bremen, 28359 Bremen, Germany Royal Business Park, Stockport, SK8 3GR United 2Bruker Daltonik GmbH, 28359 Bremen, Germany Kingdom 2 7 Agilent Technologies, Avenue des Tropiques, ZA Planktonic archaea and other marine microorganisms are Courtaboeuf 2, BP 12, 91941 Les Ulis, FRANCE known to adapt their membrane lipids to temperature – a phenomenon exploited in a number of molecular proxies for Lead is an element whose isotopic pattern naturally varies the reconstruction of past sea surface temperature (SST) from more than any other element in the periodic table. The various dated sediment cores. One widely applied proxy is the TEX stable isotopes are derived from uranium and thorium decay 86 index [1], which is based on the number of rings in the (238U – 206Pb, 235U – 207Pb; 232Th – 208Pb) with the only structure of the archaeal lipid GDGT. Given typical sample non-radiogenic isotope being the 204Pb isotope. Lead is an sizes and analysis by LC-APCI-MS, such SST records can important element for providence testing (e.g. tracing the resolve decadal to millennial variations, dependent on the origin of an atrefact, food product, pollution event etc.) and its geological setting examined. Our goal was to combine the isotope analysis has been used in applications as far afield as temperature proxy potential of lipids in the sedimentological pollution tracer studies for TEL (tetraethyl lead fuel additive), record with the high spatial resolution of laser desorption ore, olive oil & wine origin testing and forensic analysis of ionization (LDI) coupled to FT-ICRMS. Micrometer-scale bullets. resolution of LDI may produce estimates on sub-decadal to One of the most important and difficult analyses for lead sub-annual scales and potentially provide crucial, previously isotopes is for dating of minerals and Pb containing artefacts. hidden insights on the heartbeat of past climates. For successful dating, all of the stable isotopes of Pb are We demonstrate that LDI FT-ICRMS efficiently ionizes required however there is an isobaric overlap from 204Hg on GDGTs and that the high resolving power of FT-ICRMS is the 204Pb isotope. If any Hg is present in the sample, reagents crucial for their unequivocal identification. We also observe a or as a contaminant in the Ar gas, this would significantly bias strong correlation between TEX -based SST analysis by LC- the data whether solution or laser analysis is employed. 86 APCI-MS and ring distributions obtained by LDI FT-ICRMS, Removal of the Hg-based isobaric overlap can be achieved which proves the utility of the proposed method for correctly by addition of ammonia to a collision-reaction cell (CRC) quantifying the different GDGT species. equipped instrument. Mercury ions undergo rapid charge- We analyzed a several-cm long sediment core segment of transfer reaction in the presence of ammonia (the Hg+ ion is Mediterranean Sapropel S1 with a spatial resolution of neutralised to Hg0 and the charge is passed to the ammonia 200 µm, which corresponds to a temporal resolution of about molecule). 6 yrs. The observed GDGT distributions are consistent with This could lead to the successful removal of Hg isobaric short-term rhythmic variations of SST with relatively high interference from Pb – however the potential issue of new amplitudes of several °C. Further validation of these trends is molecular interferences created within the cell remain unless ongoing. These first results demonstrate the capacity to obtain the reaction can be sufficiently controlled by ion pre-selection. a continuous, high resolution profile of GDGTs directly on an This paper demonstrates the benefit of a MS/MS capable ICP- intact sediment core, thus setting the stage for lipid-based MS for the effective interference-free analysis of lead paleotemperature estimations with unprecedented temporal isotopes. resolution and suggesting an enormous potential of this

approach for future biomarker applications.

[1] Schouten et al. (2002), EPSL 204, 265-274.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2511

From zircon date to process rate: The research of sulfur early Interpreting zircon U-Pb dates in diagenesis cycle drived by AOM and igneous petrology and stratigraphy methane-seep environment in the JÖRN-FREDERIK WOTZLAW1AND URS SCHALTEGGER1 Cold Seep Area, northern South 1Section of Earth and Environmental Sciences, University of China Sea Geneva, CH-1205 Geneva, Switzerland 1 2 ([email protected]; [email protected]) DAIDAI WU AND NENGYOU WU 1Key Laboratory of Renewable Energy and Gas Hydrate of The precision of single crystal zircon U-Pb dates Guangzhou Institute of Energy Conversion, achievable by isotope dilution thermal ionization mass Chinese Academy of Sciences, Guangzhou 510640, China; spectrometry (ID-TIMS) often exceeds our ability to interpret ([email protected]) them in the context of magmatic processes. Closing this gap is 2 Key Laboratory of Renewable Energy and Gas Hydrate of presently one of the big challenges in high-precision U-Pb Guangzhou Institute of Energy Conversion, geochronology. Recent developments of analytical protocols Chinese Academy of Sciences, Guangzhou 510640, China; allowing the analysis of various isotopic ratios and trace ([email protected]) element concentrations in tandem with ID-TIMS U-Pb geochronology (e.g., Schoene et al. , 2010; Wotzlaw et al. , Abstract"The South China Sea is located at the junction 2013) significantly improved our ability to link the timing of of three tectonic plates: the Eurasian, the Pacific and the zircon crystallization to specific episodes during the lifetime Indian-Australian. The northern continental slope, the South of a magmatic system. With this contribution, we aim to China Sea, is well known for its prospect of oil, gas, gas highlight the potential and limitations of high-precison U-Pb hydrate resources. Four areas including Taixinan Basin, geochronology in petrologic and stratigraphic applications. Northeast Dongsha, Baiyun depression and Qiongdongnan We present high-n zircon U-Pb datasets of individual Basin were identified as the most favourable conditions for eruptive units from large-volume magmatic systems to gas seep or gas hydrate to occur, and were discovered investigate patterns of zircon crystallization during magma geological, geochemical and biological evidences for cold evolution from assembly to eruption. These data-sets display seeps. In the seabed Cold Seep Area, the sulfate reduction age distributions that point to discrete events of zircon drives by the organic matter oxidation, but mainly drives by crystallization that can be linked to the thermal evolution of anaerobic methane oxidation (AOM). However, the research the magmatic systems prior to eruption. When combined with of AOM-driven sulfate reduction and its important isotopic and chemical information from the same crystals, contribution to the sulfur early diagenesis cycle and sulfur individual zircons provide snapshots of the chemical and buried needs to be studied. In this parper, the sediment cores physical state of the magma at the time of zircon and cold seep carbonates were collected from the Dongsha and crystallization, allowing us to construct time-integrated Shenhu Cold Seep Area, northern South China Sea.The main petrogenetic models. However, in stratigraphic applications, geochemistry characteristics research contains the chemical where the desired age information is that of ash bed composition of pore water, the microstricture fo sulfates and deposition, the pre-eruptive magmatic history recorded by sulfides authigenic minerals, the distribution and content of zircons is a fundamental limiting factor. We use zircon U-Pb intermediate state of sulfur and organic matter sulfide, sulfur dates from ash beds intercalated with astronomically tuned and carbon stable isotope fractionation with comprehensive sedimentary sequences in the Mediterranean to test the methods such as geochemistry, mineralogy, isotope accuracy of zircon U-Pb derived age models. We evaluate geochemistry, numerical calculation methods,etc. The target is various approaches to estimate ash bed deposition and to identify the sulfate reduction drives by organic matter construct continuous age models employing different fitting oxidation or AOM, obtain the proportion of sulfate algorithms aiming to find a solution to minimize the residual consumption by AOM in the pore water, the sulfur isotope offset between radioisotopic and astronomical time. fractionation characteristics and constraints; establish a sound

sulfur cycle path in marine sediment, quantitative assessment [1] Schoene, B., Latkoczy, C., Schaltegger, U., Günther, D., the diagenesis burial flux of iron sulfide and sulfate minerals 2010, Geochimica et Cosmochimica Acta 74, 7144-7159. [2] in marine sediments and react the cold seep sedimentary Wotzlaw, J.F., Schaltegger, U., Frick, D., Dungan, M., environment characteristics. Gerdes, A., Günther, D., 2013, Geology (in press).

Acknowledgments"Funding was provided by the National Natural Science Foundation of China (No. 41003010) and (No. 
).

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2512 Goldschmidt2013 Conference Abstracts

Metasomatic perovskite Sensitivity of carbonaceous aerosol FU-YUAN WU*, JING SUN AND CHUAN-ZHOU LIU simulations to aging schemes Institute of Geology and Geophysics, Chinese Academy of SHILIANG WU1 , YAOXIAN HUANG1, Sciences, Beijing 100029, China, MANVENDRA DUBEY2 AND NANCY FRENCH1 ([email protected]) (* presenting author), 1Michigan Technological Univeristy, Houghton, MI 49931, ([email protected],)( [email protected]) USA ([email protected]) 2 Earth System Observations, Los Alamos National Laboratory, Perovskite is one of the major minerals containing Los Alamos, NM 87545, USA significant amount of U, Th, Sr, Hf and REE, which makes it a suitable mineral for U-Th-Pb dating and Sr-Nd-Hf isotopic Carbonaceous aerosols including organic carbon and black analyses by TIMS and in situ techniques[1]. Generally, carbon have significant implications for both climate and air perovskite is occurred by magmatic crystallization in quality. In the current global climate or chemical transport kimberlitic, kamafugitic, lamproitic, alkaline ultramafic and models, a fixed hydrophobic-to-hydrophilic conversion carbonatitic rocks[2], and rarely in carbonaceous chondrite[3]. lifetime for carbonaceous aerosol is generally assumed, which Metasomatic perovskite, however, is rarely reported. During is usually around one day. We have implemented a new this study, metasomatic perovskite from numerous localities detailed aging scheme for carbonaceous aerosols in a chemical were examined for its major, trace elemental compositions, transport model (GEOS-Chem) to account for both the and Sr-Nd isotopic data were used to constrain its petrogenetic chemical oxidation and the physical condensation-coagulation history. effects, where the aging is affected by local atmospheric The reported metasomatic perovskite includes those from: environment including atmospheric concentrations of water 1) Mantle peridotite xenolith in kimberlite, South Africa[4]; 2) vapor, ozone, hydroxyl radical and sulfuric acid. The updated Rodingite from Changawuzi in Tianshan, China; 3) Skarn conversion lifetime exhibits large spatial and temporal formed by contact metamorphism between syenite intrusion variations with the global average calculated to be 4.3 days. and carbonate, Tazheran, Baikal; 4) Chlorite schist formed by The chemical aging effects are found to be strongest over the dioritic intrusion into limestone in Zlatoust of Urals, Russia, tropical regions driven by the low ozone concentrations and and 5) Chlorite schist probably related to intrusion of the high humidity there. The conversion lifetime resulted from nearby syenite in San Benito of Californian, USA. chemical aging generally decreases with altitude due to Compared with those from kimberlites and alkaline increases in ozone concentration and decreases in humidity. ultramafic intrusions, metasomatic perovskite is relatively The condensation-coagulation effects are found to be most stoichiometric with higher amount of Ca and Ti. In terms of important for the high-latitude areas, in particular the polar trace elements, metasomatic perovskite has variable regions, where the 7 values are calculated to be up to 15 days. concentrations of REE, U and Th, but higher concentrations of When both the chemical aging and condensation-coagulation Zr, Hf and LREE/HREE fractionation, and lower Nb, Ta and effects are considered, the total atmospheric burdens and Sr. global average lifetimes of BC (OC) are calculated to increase According to our data, perovskite from Tazheran has the by 52% (29%) compared to the control simulation. Model lowest common lead, making it a suitable standard for in situ evaluation against data from multiple observation networks U-Pb dating. The low Sr concentration makes it impossible to worldwide shows that the updated aging scheme improves get its Sr isotopic composition using laser ablation. However, model simulations of carbonaceous aerosols, especially for the most metasomatic perovskites can be determined its Nd remote regions. Further model sensitivity simulations focusing isotopic composition by in situ method, except those from San on the continental outflow of carbonaceous aerosols San Benito, which is the most stoichiometric in major demonstrate that previous studies using the old aging scheme elements, and has the lowest REE concentrations. could have significantly underestimated the inter-continental

transport of carbonaceous aerosols. [1] Yang et al. (2009) Chem. Geol., 264, 24-42. [2]

Chakhmouradian and Mitchell (2001) Can. Mineral., 38, 975- 994. [3] Ireland et al. (1990) Earth Planet. Sci. Lett., 101, 379- 387. [4] Dawson et al. (2001) Contrib. Mineral. Petrol., 140: 720-733.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2513

Chemical weathering, atmospheric Physiology, mineralogy and Fe CO2 consumption, and the controlling isotope fractionation of Fe(II) factors of a small silicate watershed oxidation by a marine in subtropical zone photoferrotroph - Implications for WEIHUA WU1*, HONGBO ZHENG 2 AND CHAO LUO 1 the deposition of Precambrian BIFs 1 Key Laboratory of Surficial Geochemistry, Ministry of WENFANG WU1,2, ELIZABETH D. SWANNER2, YONGXIN Education; School of Earth Sciences and Engineering, PAN1, RONNY SCHOENBERG2 AND ANDREAS KAPPLER2 Nanjing University, Nanjing 210093, China. 1Institute of Geology and Geophysics, Chinese Academy of (*correspondence: [email protected]) 2 Sciences, Beijing, China, [email protected] School of Geography Science, Nanjing Normal University, 2 Department of Geoscience, University of Tuebingen, Nanjing 210046, China Germany

Hydrochemistry of a small subtropical watershed, the Anoxygenic phoferrotrophs are capable of photosynthetic Xishui River draining mainly gneisses and amphibolites is Fe(II) oxidation in the absence of oxygen. Because of this systematically investigated. By collecting samples from source ability they were suggested to be involved in the precipitation area to river mouth in summer and winter, we discuss of oxidized iron minerals in Banded Iron Formations (BIFs) temporal and spatial variations of major ion concentrations. prior to the presence of significant amounts of O2 on Earth. An inversion model is used to evaluate different contributions Although photoferrotrophs are thought to be important for from atmospheric input, anthropogenic activities and rock Fe(II) oxidation in ancient oceans, previous studies related to weathering (silicate, carbonate, and evaporite), and calculate BIFs have focused on freshwater strains [1]. However, marine chemical weathering and atmospheric CO2 consumption rates geochemistry differs from freshwater probably strongly in the catchment. affecting anoxygenic Fe(II) oxidation and consequently the The results show: (1) Major ion concentrations in summer mineralogy and Fe isotope composition of the Fe(III) minerals are mostly higher than those in winter except for Si, which produced. In this study we therefore quantified cell growth, indicates that influence of intensive weathering, agricultural Fe(II) oxidation rates, Fe isotope fractionation and mineralogy activities, and acid rain in summer exceeds dilution effect. (2) of Fe(III) precipitates during Fe(II) oxidation by the marine Contributions from atmospheric input are 13.2 % and 7.8 % in photoferrotroph Rhodovulum iodosum. We found that the winter and summer, respectively. Anthropogenic activities maximum Fe(II) oxidation rate was slower than determined provide only 2.4 % and 4.2 % major ions to the Xishui River, for the freshwater strains. The crystalline Fe(III) which has a slight influence on the hydrochemistry. oxyhydroxides goethite and lepidocrocite were produced in Contributions from silicate weathering are 52.1 % and 48.7 %, contrast to the poorly crystalline ferrihydrite that is typically and carbonate weathering are 28.4 % and 24.2 %. Therefore, produced by the freshwater strains. During Fe(II) oxidation, though area of carbonate rocks only accounts for < 5 % of the the Fe(III) precipitate enriches in the heavier Fe isotopes while drainage area, it has an important contribution to major cations the aqueous Fe(II) becomes lighter, consistent with the trend in the Xishui River. Contributions from evaporite are 3.8 % observed for freshwater strains but with a significantly smaller and 15.1 % in winter and summer, indicating that influence of fractionation factor than determined for the freshwater strain temperature on evaporite dissolution is more noticeable. (3) Thiodictyon F4 [2]. Our experiments demonstrate that Silicate weathering rates are 0.64–4.44 t/km2y and 4.1–21.2 2 anoxygenic phototrophic Fe(II) oxidation shows distinct t/km y in winter and summer, respectively. The atmospheric differences in marine settings compared to experiments done CO2 consumption rates resulted from silicate weathering are 5 2 5 2 under freshwater conditions and will ultimately allow us to 0.31–2.1&10 mol/km y and 1.94–10.2&10 mol/km y in better understand their role in the deposition of oxidized Fe winter and summer. The rates in the Xishui River are minerals in Precambrian Banded Iron Formations. remarkably lower than those in small watersheds which had higher temperature and rainfall in tropical zone, and are higher [1] Hegler et al. (2008) FEMS Microbiol. Ecol. 66: 250-260. than those in small watersheds had similar rainfall but lower [2] Croal et al. (2004) Geochim. Cosmochim. Acta 68: 1227- temperature in central Europe and eastern France, indicating 1242. that temperature may be the most important factor influenced the chemical weathering rates in silicate watersheds.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2514 Goldschmidt2013 Conference Abstracts

Pristane isomerization ratio: Elasticity of ferropericlase at lower Novel maturity index for highly mantle conditions mature and overmature oils ZHONGQING WU1,2, JOÃO F. JUSTO,1,3 1 1,2 1 1 AND RENATA M. WENTZCOVITCH YINGQIN WU , YONGLI WANG *, TIANZHU LEI , SUPING MA1, YOUXIAO WANG 1 , YUAN GAO1 AND 1Department of Chemical Engineering and Materials Science, YANQING XIA 1* University of Minnesota, Minneapolis, MN 55455 2Laboratory of Seismology and Physics of Earth's Interior, 1Key Laboratory of Petroleum Resources Research, Institute School of Earth and Space Sciences, University of Science of Geology and Geophysics, Chinese Academy of and Technology of China, Hefei, Anhui 230026, China Science, Lanzhou 730000, China 3Escola Politécnica, Universidade de São Paulo, CP 61548, ([email protected]) (*correspondence: CEP 05424-970, São Paulo, SP, Brazil [email protected],[email protected]) 2 Graduate School of the Chinese Academy of Sciences, Clarification of the effect of the iron spin state change on Beijing 100049, China properties of Fp is important to address the relative abundance Thermal maturity is an important parameter in assessing of Fp in the lower mantle. However, recent works addressing petroleum evolution in sedimentary basins. However, the this question have reached different conclusions. The maturity parameters based on biomarkers cannot be applied to calculated density of a pyrolite aggregate with spin crossover- highly mature oils (Ro > l.5%), especially to overmature oils related change in iron partitioning compared well with the et (Ro > 2.0%) (e.g. the sterane and terpane isomerization ratios, density in PREM up to 45 GPa [1]. In contrast, Murakami methyl phenanthrene index and methyl diamantane index). al’s analysis of VS in aggregates with variable amounts of Fp The reason is that these ratios reach their equilibrium values concluded that the lower mantle is more perovskitic than before or at the onset of the “oil window”. Therefore, the peak pyrolitic [2]. hydrocarbon generation stage cannot be assessed using these We investigated the thermoelasticity of Fp by first parameters, particularly for highly mature and overmature principles using the DFT+U functional. The calculated crude oils. thermoelastic coefficients are consistent with available In this experiment, pristane isomers were identified in experimental data on samples with various iron extracts from the coal samples of Junggar Basin, China. From concentrations. Results help us to understand some brown coal to subbituminous coal, corresponding to Ro 0.36- discrepancies among different experimental data sets 2.99 %, the PIR [pristane isomerization ratio =#[6(R)10(R) + regarding the shear modulus softening [3,4]. We predict 6(S)10(S)] /6(R)10(S)] ranges from 42 to 97% for the coal velocities of Fp at lower mantle conditions and suggest that extracts. The value of PIR, a molecular maturity parameter, is pyrolite is a reasonable compositional model for the lower evaluated by analyzing a series of samples from the Junggar mantle. Our results show the importance of constraining the Basin with known values of the molecular maturity parameter elastic properties of minerals without extrapolations for based on the sterane and hopane isomerization and methyl analyses of the thermochemical state of this region. phenanthrene index. Changes in the PIR in these highly mature Ai-13 (Ro>1.5%) and overmature Ha-01 and Ha-02 [1] Irifune et al. Science 327, 193 (2010). [2] Murakami et al. (Ro>2.0%) are still obvious and with linear correlation Nature 485, 90 (2012). [3] Crowhurst et al. Science 319, 451 between PIR and Ro. As a result, our results suggest that the (2008). [4] Marquardt et al. Science 324, 224 (2009). PIR is an appropriate indicator of maturity for the highly mature and overmature oils and sediments. It is clear that the PIR increases with the increasing of Ro, which possibly suggests an isomerization of RS isomer into the RR and/or SS isomer. In summary, the PIR may be potential interest as it can efficiently be used in measuring the maturity of highly mature oils, sediments and may work throughout the “oil window”. However, the same case may be expected to take place in other molecular parameters, but the current work does not observe the dependence of the PIR on the kerogen type. It is necessary to make further investigation and collect data of the PIR from other samples (elsewhere) in order to attain better results of the present study. Supported by grants No. XDB03020405, 2012CB214701, NSFC No. 41272147,41172169, 40672123 and TPR-2012-18.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2515

Anaerobic activity of nitrite-oxidizing Geochemical impacts of carbon microorganisms affects the #18O of dioxide leakage into carbonate dissolved nitrate during microbial aquifer rocks denitrification ASSAF WUNCH1, ALEXIS SITCHLER2, JOEL MOORE3 AND 4 12* 1 JOHN E. MCCRAY ANJA WUNDERLICH , RAINER U. MECKENSTOCK AND FLORIAN EINSIEDL2 1Hydrologic Science and Engineering Program, Colorado 1 School of Mines, Golden CO 80401, [email protected] Institute of Groundwater Ecology, Helmholtz Center 2 Geology and Geological Engineering Department, Colorado Munich, Ingolstädter Landstraße 1, Neuherberg, Germany School of Mines, Golden CO 80401, [email protected] ([email protected]) 3 2 Department of Physics, Astronomy and Goesciences, Technische Universität München, Chair of Hydrogeology, Towson Univerity, Towson MD 21252, Arcisstrasse 21, Munich, Germany ([email protected]) 4 Civil and Environmental Engineering Department, Colorado The stable isotopes of nitrate in water are frequently used School of Mines, Golden CO 80401, [email protected] to assess denitrification and sources of nitrate in the

environment. It was previously assumed for terrestrial Leakage of CO during geological carbon sequestration environments that a relative increase in "18O of nitrate 2 can prevent meeting environmental and storage goals. A compared to its "15N of 0.5 is indicative of denitrification. significant environmental concern is acidification of We anaerobically incubated sediments with natural groundwater with a potential subsequent increase in aqueous microbial populations from 3 different anoxic habitats and a metal concentrations due to mineral dissolution and pure culture of the nitrite oxidizing bacterium Nitrobacter desorption. Even though carbonate aquifers supply about 20% vulgaris in strongly 18O-labeled water with nitrate and of drinking water worldwide, these aquifers are somewhat adequate electron donors. A significant influence of "18O of neglected in the CO sequestration literature, because water on the "18O of nitrate was found in all experiments. All 2 carbonate minerals are presumed to buffer pH increases. The incubations clearly expressed microbial denitrification. Given common carbonate minerals (calcite, dolomite) are rarely oxic conditions, the microbial populations of all incubations found in pure form in nature, and typically contain metal were also able to oxidize nitrite. We thus assume the presence impurites. Dissolution of these minerals is very sensitive to of nitrite oxidizing microorganisms in all incubations. As pH changes, and we hypothesized that metals could be nitrite oxidizers may catalyze the observed isotopic shift in released during carbonate dissolution. Previous studies pure cultures, they are likely also the driving parameter of the usually point to sulfide minerals as likely sources of toxic observed shift in the environmental incubations. This shift metals. Pressurized experiments containing natural carbonate questions the stability of predicted 3"18O/3"15N ratios in the rocks at elevated CO pressures resulted in elevated aqueous environment during denitrification. Such a shift in "18O of 2 concentrations of Mn, Ni, As, Cr, Sr, Ba, Co, Mo and Tl, with nitrate under anoxic conditions also questions the validity of few elements rising above U.S. regulatory limits. nitrate source determination by 2D isotopic fingerprinting, Geochemical modeling (constrained by our experimental specifically in respect to the "18O axis. results) suggest that carbonate minerals may be the dominant Nitrite oxidizing microorganisms possess a nitrite contributors to metal release in a carbonate aquifers, not oxidoreductase enzyme (NXR) which is able to oxidize nitrite pyrite. Consequently, models that ignore co-release of metals as well as reduce nitrate, depending on the redox conditions. from carbonates may underpredict metal release. However, Regular denitrifiers possess a nitrate reductase (Nar) which geochemical modeling also demonstrates that pyrite may be an only reduces nitrate irreversibly. We hypothesize that the important source of metals under oxidizing conditions, and nitrate reduction reaction at the NXR enzyme by nitrite that the influence of O partial pressures is equally important oxidizing microorganisms is reversible even under anoxic 2 that of CO2. conditions, allowing the incorporation of oxygen-atoms from

water into nitrate. - + - NO3 + 2H # NO2 + H2O It is likely that a variable activity of nitrite oxidizers in anoxic environments produces a variable shift of "18O of nitrate towards "18O of ambient water and thus varied ratios of 3"18O/3"15N.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2516 Goldschmidt2013 Conference Abstracts

Microbial metabolic processes in the Geoneutrino detection in the future deep subsurface - impact on low-energy neutrino observatory geological energy storage LENA HILKE WÜRDEMANN1*, DARIA MOROZOVA1, STEPHANIE MICHAEL WURM LERM1, ANKE WESTPHAL, MONIKA KASINA1 LINDA Eberhard Karls Universität Tübingen, 72076 Tübingen, PELLIZZARI1, HANANAH HALM1 Germany AND DOMINIK NEUMANN1

1Helmholtz Centre Potsdam, GFZ German Research Centre The next-generation liquid-scintillator detector LENA for Geosciences, 14473 Potsdam, Germany (Low Energy Neutrino Astronomy) will be a versatile tool for the study of low-energy neutrino fluxes. Following up on the Enhanced process understanding of engineered reservoirs first successful measurements of geoneutrinos by the is a prerequisite to optimize the operation of geological KamLand and Borexino experiments, LENA is aiming at a storage, to increase the reliability as well as to assess the risks high-statistics measurement of the geoneutrino flux above 1.8 involved. Since microorganisms are very effective MeV. Like its predecessors, LENA will profit from the low geochemical catalysts and their contribution to the mineral energy threshold and the excellent background discrimination alteration and dissolution needs to be investigated. capabilities of the liquid scintillator technique, but above all The microbial diversity of a different reservoirs in the from its in comparison considerably larger target mass of 50 North German Basin, the Upper Rhine Graben, the Molasse kiloton. Basis and the Styrian Bassin was analysed with molecular For the preferred experimental site, the Pyhäsalmi mine in biological and geochemical methods. Interactions of central Finland, we expect about 1000 inverse beta decay microbial activity with the geotechnical use of the reservoirs events per year. Far from the majority of nuclear power plants,

were studied in a pilot plant for CO2 storage, in bypass the expected geoneutrino signal to reactor neutrino systems of a geothermal heat store and in long-term laboratory background ratio at this site is of the order of 2:1. Based on experiments with rock cores and reservoir fluids. Genetic the predicted event rate and 10 years of exposure, the fingerprinting analyses revealed distinct microbial geoneutrino flux could be determined at 1% level. This will communities in fluids depending on the temperature, the open the door for a precise determination of the radiogenic salinity and the availability of electron donors like organic contribution to the terrestrial heat flow and the discrimination substances or hydrogen. Cell counting and quantification of of geological models. Moreover, the detected geoneutrino 16S rRNA genes and dissimilatory sulfite reductase (dsrA) spectrum can be evaluated to determine the relative genes by real-time PCR proved different population sizes in contributions of beta-decays from the uranium and thorium fluids, showing higher abundance of Bacteria and sulfate decay chains to the overall neutrino flux. After 10 years, an reducing bacteria (SRB) in systems influcenced by corrosion. accuracy of 5% could be reached for the U/Th ratio, thereby SRB were accounted for corrosion damage and iron sulfide reaching a level of precision relevant for the study of precipitates in the near wellbore area that affected plant terrestrial models. reliability adversely.

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 Goldschmidt2013 Conference Abstracts 2517

The volatile content of Mount Etna Seasonal distinction of hydrological magma: An FTIR and Raman study variability in speleothem calcite of glassy melt inclusions WYNN, P.M.1* FAIRCHILD, I.J.2 SPÖTL, C.3 HARTLAND, A.4 MATTEY, D.5 COTTE, AND M6. FAYARD, B6,7 ROBIN WYLIE 1Lancaster University, Lancaster, UK. (*correspondance University College London, London WC1E 6BT [email protected]) (correspondence: [email protected]) 2 University of Birmingham, Birmingham, UK The 1983 eruption of Mount Etna ([email protected]) 3Leopold-Franzens-Universität Innsbruck, Innsbruck, AT. Mount Etna volcano, Sicily, is amongst the highest ([email protected]) emitters of volcanic carbon dioxide worldwide, however the 4University of Waikato, Hamilton, New Zealand. origin of this prolific output is still debated. As such, ([email protected]) characterising the occurrence of CO in Mount Etna magmas 2 5Royal Holloway University of London, UK has important implications for our understanding of deep ([email protected]) Earth degassing. 6European Synchrotron Radiation Facility, Grenoble, FR Lavas from the 1983 eruption of Mount Etna have been ([email protected]) found to contain native carbon, in the form of graphite and 7 Université Paris-Sud, F-91405, FR diamond [Adrian Jones, pers. comm.]. This unprecedented ([email protected]) observation suggests that this, so far little-studied eruption,

may have sampled an unusually deep source of carbon beneath Speleothem chemical records have been employed in the Etna. These lavas therefore represent an ideal target for the reconstruction of environmental change on a broad range of further characterisation of the carbon output of this volcano. timescales. Whilst sub-annual records are scarce, it is here that By the time they are erupted, lavas are heavily depleted in one of the research frontiers resides, providing a modern CO , as it begins to degas at large depths within the volcanic 2 calibration between speleothem proxy and meteorological system. Melt inclusions are small pockets of magma which conditions. Here, we use Synchrotron µXRF spectrometry at become trapped within crystals growing within a magma ID21, ESRF, to reveal trace element patterns of Zn, Pb and S body, and – as they are isoltated from the effects of degassing within speleothem calcite over three annual cycles. In this – can preserve the early volatile composition of magmas. way, archived signals are calibrated to modes of trace element Importantly, the analysis of H O together with CO allows the 2 2 incorporation and meteorological conditions. Concentrations trapping depth of these inclusions to be estimated. Work plan of Zn and Pb in speleothem Obi84 show in-phase cyclicity and are attributed to transport in complexes with natural organic Glassy melt inclusions, hosted within olivine phenocrysts matter (NOM) originating from the soil/epikarst above the from lavas of the 1983 Etna eruption, will be analysed using cave. Peak fluorescent laminae occur on an annual basis, FTIR (Fourier Transform Infra Red) Spectroscopy, and although banding of lower fluorescence intensity reveals Raman microscopy, in order to determine the concentrations multiple events at the sub-annual scale. Meteorological data of dissolved CO and H O, respectively, in the glasses. Using 2 2 reveals the delivery of NOM-metal complexes to the the Raman method, the presence of H O has already been 2 speleothem is dependent upon water excess, snowpack verified in the inclusions (fig. 1), and FTIR analysis will be condition, and soil microbiological activity. Sulphur performed on the same samples, starting in April 2013. demonstrated annual cyclicity, with minimum and maximum

concentrations coinciding with winter and summer

respectively, dependent upon internal cave atmospheric Melt inclusion conditions and the pH value to which cave drip waters degas.

At the current resolution of analysis, this represents some of

H2O the first evidence linking event-based meteorological records 75µm to the trace element content of speleothem calcite and is the 650 1650 2650 3650 Raman shift (cm-1) initial phase of work which aims at developing records of

seasonal infiltration patterns and cave ventilation dynamics, Fig. 1. Left: Sample prepared melt inclusion within its olvine host crystal; Right: building towards proxy records of winter duration and Raman microprobe spectrum of the same inclusion, which shows a prominent seasonal infiltration patterns as indices of climatic change. OH peak indicating the presence of dissolved H O. 2

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021 2518 Goldschmidt2013 Conference Abstracts

In situ determination of REE in clinopyroxene from syenites IRENA WYSOCKA1 AND EWA KRZEMINSKA1 1Polish Geological Institute-National Research Institute, 00- 975 Warszawa, 4 Rakowiecka, Poland ([email protected];)( [email protected])

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has became widely used method for the geological applications. In this work, the distribution of rare earth elements (REEs) in clinopyroxene (cpx) was studied. Cpx is significant mineral phase in foid syenite to syenite, which are late differentiates of alkaline–ultramafic Carboniferous igneous suite of Tajno and E2k (Poland). The analyses were restricted to the phenocrysts with about 400 - 500 %m width, chemically classified as a diopside and eagirine augite. Determination of the trace element concentrations in cpx were performed by laser ablation system LSX-500 (UV Nd:YAG 266 nm, Cetac) connected to the quadruple mass spectrometer (Elan DRC II, Perkin Elmer Sciex). The ablation conditions (spot diameter, energy and pulse rate) were optimised separately for the rocks and the thin sections. The applied spot size was 50 or 100 %m. Cpxs were analysed for REE and trace element content using frequency of 10 Hz or 5 Hz. The measurements were carried out in-situ in the polished rocks and in thin sections (thickness of ~ 100-120 µm). The same thin sections and polished rock samples of each syenite were also imaged by BSE and analyzed by WDS Cameca SX100 electron microprobe at the aim of the determination of the main chemical components. The synthetic silicate certified reference materials NIST 610 and NIST 612 were used for method calibration and BIR-1, BCR- 2 and BHVO-2 were used for the verification of the obtained results. Different element oxides were applied as the internal standards and the results were compared. Based on the performed analyses we have concluded that: 1) LA-ICP-MS is appropriate method for in-situ measurements in the polished rocks and in thin sections of minerals and results are comparable; 2) the pronounced differences in REE content in cpx of different origin were observed; 3) the variation of the REE contents in cpx phenocrysts from alkali silicate host rocks may reflect slightly different melt evolution paths of the complexes with (Tajno syenite) and without associated carbonatites (E2k syenite).

www.minersoc.org DOI:10.1180/minmag.2013.077.5.23

Downloaded from http://pubs.geoscienceworld.org/minmag/article-pdf/77/5/2435/2920915/gsminmag.77.5.23-W.pdf by guest on 29 September 2021