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Handbook of Iron Meteorites, Volume 3
Sierra Blanca - Sierra Gorda 1119 ing that created an incipient recrystallization and a few COLLECTIONS other anomalous features in Sierra Blanca. Washington (17 .3 kg), Ferry Building, San Francisco (about 7 kg), Chicago (550 g), New York (315 g), Ann Arbor (165 g). The original mass evidently weighed at least Sierra Gorda, Antofagasta, Chile 26 kg. 22°54's, 69°21 'w Hexahedrite, H. Single crystal larger than 14 em. Decorated Neu DESCRIPTION mann bands. HV 205± 15. According to Roy S. Clarke (personal communication) Group IIA . 5.48% Ni, 0.5 3% Co, 0.23% P, 61 ppm Ga, 170 ppm Ge, the main mass now weighs 16.3 kg and measures 22 x 15 x 43 ppm Ir. 13 em. A large end piece of 7 kg and several slices have been removed, leaving a cut surface of 17 x 10 em. The mass has HISTORY a relatively smooth domed surface (22 x 15 em) overlying a A mass was found at the coordinates given above, on concave surface with irregular depressions, from a few em the railway between Calama and Antofagasta, close to to 8 em in length. There is a series of what appears to be Sierra Gorda, the location of a silver mine (E.P. Henderson chisel marks around the center of the domed surface over 1939; as quoted by Hey 1966: 448). Henderson (1941a) an area of 6 x 7 em. Other small areas on the edges of the gave slightly different coordinates and an analysis; but since specimen could also be the result of hammering; but the he assumed Sierra Gorda to be just another of the North damage is only superficial, and artificial reheating has not Chilean hexahedrites, no further description was given. -
Structure and Composition OXIDATION ZONE
OXIDATION ZONE Structure and Composition The first scanty information on the oxidation zone of the Rubtsovskoe deposit was obtained as a result of drilling in the early 1970s. Three major subzones were distinguished downward: (1) a leached oxidized ore zone largely composed of iron hydroxides and kaolinite; (2) a secondary oxide enrichment subzone with cuprite, native copper, malachite, azurite, cerus - site; and (3) a secondary sulfide enrichment subzone (that transitions to an underlying zone of mixed ores) with chalcocite and covellite (Stroitelev et al. , 1996). As a result of our observation in underground workings, the structure, min - eralogy, and genetic features of the oxidation zone of the deposit were spec - ified substantially. The top of the orebody is supergene altered to the highest degree at the WSW flank, where it is located higher in altitude. The upper boundary of the orebody gently plunges ENE and the oxidation zone (we do not discuss the mixed ores) gradually pinches out; the oxidation zone extends along the strike of the orebody for approximately 300 m. In the WSW part of the ore - body, the oxidized ores occur in the altitude interval from +137–138 to +163 m. The lower boundary of the oxidized ores rise toward the ESE and the main part of the oxidation zone occurs in the range of +144–145 to +153–157 m. The oxidized part of the orebody varies from 2 to 8 m in thickness, reaching 15–17 m in swells and occasionally more than 20 m. Both underlying and overlapping rocks are dominated by clayey minerals; these are wall-rock argillaceous alterations, frequently altered as a result of ore oxidation especially adjacent to the contact of the orebody. -
Handbook of Iron Meteorites, Volume 2 (Canyon Diablo, Part 2)
Canyon Diablo 395 The primary structure is as before. However, the kamacite has been briefly reheated above 600° C and has recrystallized throughout the sample. The new grains are unequilibrated, serrated and have hardnesses of 145-210. The previous Neumann bands are still plainly visible , and so are the old subboundaries because the original precipitates delineate their locations. The schreibersite and cohenite crystals are still monocrystalline, and there are no reaction rims around them. The troilite is micromelted , usually to a somewhat larger extent than is present in I-III. Severe shear zones, 100-200 J1 wide , cross the entire specimens. They are wavy, fan out, coalesce again , and may displace taenite, plessite and minerals several millimeters. The present exterior surfaces of the slugs and wedge-shaped masses have no doubt been produced in a similar fashion by shear-rupture and have later become corroded. Figure 469. Canyon Diablo (Copenhagen no. 18463). Shock The taenite rims and lamellae are dirty-brownish, with annealed stage VI . Typical matte structure, with some co henite crystals to the right. Etched. Scale bar 2 mm. low hardnesses, 160-200, due to annealing. In crossed Nicols the taenite displays an unusual sheen from many small crystals, each 5-10 J1 across. This kind of material is believed to represent shock annealed fragments of the impacting main body. Since the fragments have not had a very long flight through the atmosphere, well developed fusion crusts and heat-affected rim zones are not expected to be present. The energy responsible for bulk reheating of the small masses to about 600° C is believed to have come from the conversion of kinetic to heat energy during the impact and fragmentation. -
Liroconite Cu2al(Aso4)(OH)4 • 4H2O C 2001-2005 Mineral Data Publishing, Version 1
Liroconite Cu2Al(AsO4)(OH)4 • 4H2O c 2001-2005 Mineral Data Publishing, version 1 Crystal Data: Monoclinic. Point Group: 2/m. Typically as crystals with a flattened octahedral or lenticular aspect, dominated by {110} and {011} and striated parallel to their intersections, also {001}, {010}, {100}, to 3.6 cm, alone and in sub-parallel groups. May be granular, massive. Physical Properties: Cleavage: On {110}, {011}, indistinct. Fracture: Uneven to conchoidal. Hardness = 2–2.5 D(meas.) = 2.94–3.01 D(calc.) = [3.03] Optical Properties: Transparent to translucent. Color: Sky-blue, bluish green, verdigris-green, emerald-green; pale blue to pale bluish green in transmitted light. Streak: Pale blue to pale green. Luster: Vitreous to resinous. Optical Class: Biaxial (–). Orientation: Y = b; Z ∧ a =25◦. Dispersion: r< v,moderate. α = 1.612(3) β = 1.652(3) γ = 1.675(3) 2V(meas.) = n.d. 2V(calc.) = 72(5)◦ Cell Data: Space Group: I2/a. a = 12.664(2) b = 7.563(2) c = 9.914(3) β =91.32(2)◦ Z=4 X-ray Powder Pattern: Cornwall, England. 6.46 (10), 3.01 (10), 5.95 (9), 2.69 (6), 3.92 (5), 2.79 (5), 2.21 (5) Chemistry: (1) (2) P2O5 3.73 As2O5 23.05 26.54 Al2O3 10.85 11.77 Fe2O3 0.98 CuO 36.38 36.73 H2O 25.01 24.96 Total 100.00 100.00 • (1) Cornwall, England. (2) Cu2Al(AsO4)(OH)4 4H2O. Occurrence: A rare secondary mineral in the oxidized zone of some copper deposits. Association: Olivenite, chalcophyllite, clinoclase, cornwallite, strashimirite, malachite, cuprite, “limonite”. -
Formation of Chrysocolla and Secondary Copper Phosphates in the Highly Weathered Supergene Zones of Some Australian Deposits
Records of the Australian Museum (2001) Vol. 53: 49–56. ISSN 0067-1975 Formation of Chrysocolla and Secondary Copper Phosphates in the Highly Weathered Supergene Zones of Some Australian Deposits MARTIN J. CRANE, JAMES L. SHARPE AND PETER A. WILLIAMS School of Science, University of Western Sydney, Locked Bag 1797, Penrith South DC NSW 1797, Australia [email protected] (corresponding author) ABSTRACT. Intense weathering of copper orebodies in New South Wales and Queensland, Australia has produced an unusual suite of secondary copper minerals comprising chrysocolla, azurite, malachite and the phosphates libethenite and pseudomalachite. The phosphates persist in outcrop and show a marked zoning with libethenite confined to near-surface areas. Abundant chrysocolla is also found in these environments, but never replaces the two secondary phosphates or azurite. This leads to unusual assemblages of secondary copper minerals, that can, however, be explained by equilibrium models. Data from the literature are used to develop a comprehensive geochemical model that describes for the first time the origin and geochemical setting of this style of economically important mineralization. CRANE, MARTIN J., JAMES L. SHARPE & PETER A. WILLIAMS, 2001. Formation of chrysocolla and secondary copper phosphates in the highly weathered supergene zones of some Australian deposits. Records of the Australian Museum 53(1): 49–56. Recent exploitation of oxide copper resources in Australia these deposits are characterized by an abundance of the has enabled us to examine supergene mineral distributions secondary copper phosphates libethenite and pseudo- in several orebodies that have been subjected to intense malachite associated with smaller amounts of cornetite and weathering. -
Nonchondritic Meteorites Posters
Lunar and Planetary Science XXXIX (2008) sess608.pdf Thursday, March 13, 2008 POSTER SESSION II: NONCHONDRITIC METEORITES 6:30 p.m. Fitness Center Greenwood R. C. Franchi I. A. Gibson J. M. How Useful are High-Precision Δ 17O Data in Defining the Asteroidal Sources of Meteorites?: Evidence from Main-Group Pallasites, Primitive and Differentiated Achondrites [#2445] High-precision oxygen isotope analysis is capable of revealing important information about the relationship between different meteorite groups. New data confirm that the main-group pallasites are from a distinct source to either the HEDs or mesosiderites. Dobrica E. Moine B. Poitrasson F. Toplis M. J. Bascou J. Rare Earth Element Insight into the Petrologic Evolution of the Acapulcoite-Lodranite Parent Body [#1327] In this study we present petrological and geochemical constraints on the evolution of the acapulcoite-lodranite (A-L) parent body with emphasis on new rare earth element (REE). Bascou J. Dobrica E. Maurice C. Moine B. Toplis M. J. Texture Analysis in Acapulco and Lodran Achondrites [#1317] EBSD-measured lattice-preferred orientation of minerals of both Acapulco and Lodran achondrites have been analyzed and combined with petrological and geochemical investigations providing new constraints on the melt extraction and migration processes. Rumble D. III Irving A. J. Bunch T. E. Wittke H. J. Kuehner S. M. Oxygen Isotopic and Petrological Diversity Among Brachinites NWA 4872, NWA 4874, NWA 4882 and NWA 4969: How Many Ancient Parent Bodies? [#1974] Brachinites, related ultramafic achondrites and Graves Nunataks 06128 may derive from an incompletely-heated, heterogeneous “planetary” parent body. Petitat M. Kleine T. Touboul M. -
1 Revision 1 Single-Crystal Elastic Properties of Minerals and Related
Revision 1 Single-Crystal Elastic Properties of Minerals and Related Materials with Cubic Symmetry Thomas S. Duffy Department of Geosciences Princeton University Abstract The single-crystal elastic moduli of minerals and related materials with cubic symmetry have been collected and evaluated. The compiled dataset covers measurements made over an approximately seventy year period and consists of 206 compositions. More than 80% of the database is comprised of silicates, oxides, and halides, and approximately 90% of the entries correspond to one of six crystal structures (garnet, rocksalt, spinel, perovskite, sphalerite, and fluorite). Primary data recorded are the composition of each material, its crystal structure, density, and the three independent nonzero adiabatic elastic moduli (C11, C12, and C44). From these, a variety of additional elastic and acoustic properties are calculated and compiled, including polycrystalline aggregate elastic properties, sound velocities, and anisotropy factors. The database is used to evaluate trends in cubic mineral elasticity through consideration of normalized elastic moduli (Blackman diagrams) and the Cauchy pressure. The elastic anisotropy and auxetic behavior of these materials are also examined. Compilations of single-crystal elastic moduli provide a useful tool for investigation structure-property relationships of minerals. 1 Introduction The elastic moduli are among the most fundamental and important properties of minerals (Anderson et al. 1968). They are central to understanding mechanical behavior and have applications across many disciplines of the geosciences. They control the stress-strain relationship under elastic loading and are relevant to understanding strength, hardness, brittle/ductile behavior, damage tolerance, and mechanical stability. Elastic moduli govern the propagation of elastic waves and hence are essential to the interpretation of seismic data, including seismic anisotropy in the crust and mantle (Bass et al. -
The Albert Silver Mine and Trippkeite Occurrence, Mpumalanga, South Africa
The Albert silver mine and trippkeite occurrence, Mpumalanga, South Africa Paul M.P.B. Meulenbeld, Department of Water Affairs PO Box 1675 Bronkhorstspruit South Africa, [email protected]. Wiebke Grote, Department of Geology University of Pretoria, Private bag X20 Hatfield, Pretoria 0028, [email protected] Sabine Verryn, XRD Analytical & Consulting, Pretoria, 75 Kafue street Lynnwood Glen, 0081, [email protected] Dr. Paul M.P.B. Meulenbeld is a scientific manager with the Department of Water Affairs, a trained geophysicist and mineral collector. He has a sound knowledge about southern Africa’s mineral deposits and visits abandoned mines in his spare time. One of his last remarkable discoveries was the occurrence of chapmanite at the old Argent silver and lead deposit, Delmas, Mpumalanga, South Africa. Wiebke Grote is responsible for XRD analysis at the Department of Geology, University of Pretoria where prior to this position she was the curator of the geological museum at the same institution. Dr. Sabine Verryn is the owner of XRD Analytical & Consulting. She is the current Vice chair of the Mineralogical Association of South Africa. INTRODUCTION Around 1885 the ore deposit of the Albert Silver mine was discovered and production continued intermittently until 1914 (Robb, Robb, and Walraven 1994). The Albert Silver mine is situated on the farm Roodepoortjie 250JR, north of Bronkhorstspruit, some 80 km east-northeast of Pretoria in Mpumalanga, South Africa (Figure 1) (Robb, Robb, and Walraven 1994). No detailed description of the mine is known to have been published, but a layout plan and a plan indicating the extent of the underground workings (Figure 2), amongst a surface geophysical study of the ore bodies was given by Van Zijl (1965). -
Journal of the Russell Society, Vol 4 No 2
JOURNAL OF THE RUSSELL SOCIETY The journal of British Isles topographical mineralogy EDITOR: George Ryba.:k. 42 Bell Road. Sitlingbourn.:. Kent ME 10 4EB. L.K. JOURNAL MANAGER: Rex Cook. '13 Halifax Road . Nelson, Lancashire BB9 OEQ , U.K. EDITORrAL BOARD: F.B. Atkins. Oxford, U. K. R.J. King, Tewkesbury. U.K. R.E. Bevins. Cardiff, U. K. A. Livingstone, Edinburgh, U.K. R.S.W. Brai thwaite. Manchester. U.K. I.R. Plimer, Parkvill.:. Australia T.F. Bridges. Ovington. U.K. R.E. Starkey, Brom,grove, U.K S.c. Chamberlain. Syracuse. U. S.A. R.F. Symes. London, U.K. N.J. Forley. Keyworth. U.K. P.A. Williams. Kingswood. Australia R.A. Howie. Matlock. U.K. B. Young. Newcastle, U.K. Aims and Scope: The lournal publishes articles and reviews by both amateur and profe,sional mineralogists dealing with all a,pecI, of mineralogy. Contributions concerning the topographical mineralogy of the British Isles arc particularly welcome. Not~s for contributors can be found at the back of the Journal. Subscription rates: The Journal is free to members of the Russell Society. Subsc ription rates for two issues tiS. Enquiries should be made to the Journal Manager at the above address. Back copies of the Journal may also be ordered through the Journal Ma nager. Advertising: Details of advertising rates may be obtained from the Journal Manager. Published by The Russell Society. Registered charity No. 803308. Copyright The Russell Society 1993 . ISSN 0263 7839 FRONT COVER: Strontianite, Strontian mines, Highland Region, Scotland. 100 mm x 55 mm. -
Texture, Chemical Composition and Genesis of Schreibersite in Iron Meteorite
Title Texture, Chemical Composition and Genesis of Schreibersite in Iron Meteorite Author(s) Yoshikawa, Masahide; Matsueda, Hiroharu Citation 北海道大学理学部紀要, 23(2), 255-280 Issue Date 1992-08 Doc URL http://hdl.handle.net/2115/36782 Type bulletin (article) File Information 23-2_p255-280.pdf Instructions for use Hokkaido University Collection of Scholarly and Academic Papers : HUSCAP Jour. Fac. Sci ., Hokkaido Univ., Ser. IV, vol. 23, no. 2, Aug., 1992. pp. 255 -280 TEXTURE, CHEMICAL COMPOSITION AND GENESIS OF SCHREIBERSITE IN IRON METEORITE by Masahide Yoshikawa* and Hiroharu Matsueda (with 13 text-figures, 9 tables and 3 plates) Abstract Thirteen iron meteorites composed of Hexahedrite, Octahedrite and Ataxite were investigated to estimate their cooling history and origin. They are mainly composed of Fe-Ni metals (kamacite and taenite) with smaller amounts of schreibersite (Fe, Ni)3P and sulfides (troilite and sphalerite) . Schreibersite occurs an idiomorphic and xenomorphic crystals and its mode of occurrence is variable in iron meteorites. Xenomorphic schreibersite is subdivided into 6 types on the basis of their textures and relationships with coexisting minerals. Chemical composition of schreibersite varies from 20 to 40 atom. % Ni with textural types among some iron meteorites with different bulk chemical compositions and even in the same meteorite (e. g. Canyon Diablo), while it does not vary so clear with textural types in ALH - 77263. Schreibersite seems to maintain a local equilibrium with coexisting metal phases. Based on the Fe- Ni- P phase diagram, it is estimated that xenomorphic and coarse-grained schreibersite in Y- 75031 and in DRPA 7S007 were crystallized from stability field of taenite and schreibersite at about SOO°C under rapid diffusion conditions. -
General Index Vols. XLI-L, Third Series
GENERAL INDEX OF VOLUMES XLI-L OF THE THIRD SERIES. WInthe references to volumes xli to I, only the numerals i to ir we given. NOTE.-The names of mineral8 nre inaerted under the head ol' ~~IBERALB:all ohitllary notices are referred to under OBITUARY. Under the heads BO'PANY,CHK~I~TRY, OEOLO~Y, Roo~s,the refereuces to the topics in these department8 are grouped together; in many cases, the same references appear also elsewhere. Alabama, geological survey, see GEOL. REPORTSand SURVEYS. Abbe, C., atmospheric radiation of Industrial and Scientific Society, heat, iii, 364 ; RIechnnics of the i. 267. Earth's Atmosphere, v, 442. Alnska, expedition to, Russell, ii, 171. Aberration, Rayleigh, iii, 432. Albirnpean studies, Uhler, iv, 333. Absorption by alum, Hutchins, iii, Alps, section of, Rothpletz, vii, 482. 526--. Alternating currents. Bedell and Cre- Absorption fipectra, Julius, v, 254. hore, v, 435 ; reronance analysis, ilcadeiny of Sciences, French, ix, 328. Pupin, viii, 379, 473. academy, National, meeting at Al- Altitudes in the United States, dic- bany, vi, 483: Baltimore, iv, ,504 : tionary of, Gannett, iv. 262. New Haven, viii, 513 ; New York, Alum crystals, anomalies in the ii. 523: Washington, i, 521, iii, growth, JIiers, viii, 350. 441, v, 527, vii, 484, ix, 428. Aluminum, Tvave length of ultra-violet on electrical measurements, ix, lines of, Runge, 1, 71. 236, 316. American Association of Chemists, i, Texas, Transactions, v, 78. 927 . Acoustics, rrsearchesin, RIayer, vii, 1. Geological Society, see GEOL. Acton, E. H., Practical physiology of SOCIETYof AMERICA. plants, ix, 77. Nuseu~nof Sat. Hist., bulletin, Adams, F. -
Thermal Equilibration of Iron Meteorite and Pallasite Parent Bodies Recorded at the Mineral Scale by Fe and Ni Isotope Systematics
Available online at www.sciencedirect.com ScienceDirect Geochimica et Cosmochimica Acta 217 (2017) 95–111 www.elsevier.com/locate/gca Thermal equilibration of iron meteorite and pallasite parent bodies recorded at the mineral scale by Fe and Ni isotope systematics Stepan M. Chernonozhkin a,b, Mona Weyrauch c, Steven Goderis a,b,⇑, Martin Oeser c, Seann J. McKibbin b, Ingo Horn c, Lutz Hecht d, Stefan Weyer c, Philippe Claeys b, Frank Vanhaecke a a Ghent University, Department of Analytical Chemistry, Campus Sterre, Krijgslaan 281–S12, 9000 Ghent, Belgium b Vrije Universiteit Brussel, Analytical, Environmental, and Geo-Chemistry, Pleinlaan 2, 1050 Brussels, Belgium c Leibniz Universita¨t Hannover, Institute of Mineralogy, Callinstrasse 3, 30167 Hannover, Germany d Museum fu¨r Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstrasse 43, 10115 Berlin, Germany Received 6 January 2017; accepted in revised form 9 August 2017; Available online 19 August 2017 Abstract In this work, a femtosecond laser ablation (LA) system coupled to a multi-collector inductively coupled plasma-mass spec- trometer (fs-LA-MC-ICP-MS) was used to obtain laterally resolved (30–80 lm), high-precision combined Ni and Fe stable isotope ratio data for a variety of mineral phases (olivine, kamacite, taenite, schreibersite and troilite) composing main group pallasites (PMG) and iron meteorites. The stable isotopic signatures of Fe and Ni at the mineral scale, in combination with the factors governing the kinetic or equilibrium isotope fractionation processes, are used to interpret the thermal histories of small differentiated asteroidal bodies. As Fe isotopic zoning is only barely resolvable within the internal precision level of the isotope ratio measurements within a single olivine in Esquel PMG, the isotopically lighter olivine core relative to the rim 56/54 (D Ferim-core = 0.059‰) suggests that the olivines were largely thermally equilibrated.