Crystal Structure and Some Thermodynamic Properties of Ca7mgsi4o16-Bredigite
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List of New Mineral Names: with an Index of Authors
415 A (fifth) list of new mineral names: with an index of authors. 1 By L. J. S~v.scs~, M.A., F.G.S. Assistant in the ~Iineral Department of the,Brltish Museum. [Communicated June 7, 1910.] Aglaurito. R. Handmann, 1907. Zeita. Min. Geol. Stuttgart, col. i, p. 78. Orthoc]ase-felspar with a fine blue reflection forming a constituent of quartz-porphyry (Aglauritporphyr) from Teplitz, Bohemia. Named from ~,Xavpo~ ---- ~Xa&, bright. Alaito. K. A. ~Yenadkevi~, 1909. BuU. Acad. Sci. Saint-P6tersbourg, ser. 6, col. iii, p. 185 (A~am~s). Hydrate~l vanadic oxide, V205. H~O, forming blood=red, mossy growths with silky lustre. Founi] with turanite (q. v.) in thct neighbourhood of the Alai Mountains, Russian Central Asia. Alamosite. C. Palaehe and H. E. Merwin, 1909. Amer. Journ. Sci., ser. 4, col. xxvii, p. 899; Zeits. Kryst. Min., col. xlvi, p. 518. Lead recta-silicate, PbSiOs, occurring as snow-white, radially fibrous masses. Crystals are monoclinic, though apparently not isom0rphous with wol]astonite. From Alamos, Sonora, Mexico. Prepared artificially by S. Hilpert and P. Weiller, Ber. Deutsch. Chem. Ges., 1909, col. xlii, p. 2969. Aloisiite. L. Colomba, 1908. Rend. B. Accad. Lincei, Roma, set. 5, col. xvii, sere. 2, p. 233. A hydrated sub-silicate of calcium, ferrous iron, magnesium, sodium, and hydrogen, (R pp, R',), SiO,, occurring in an amorphous condition, intimately mixed with oalcinm carbonate, in a palagonite-tuff at Fort Portal, Uganda. Named in honour of H.R.H. Prince Luigi Amedeo of Savoy, Duke of Abruzzi. Aloisius or Aloysius is a Latin form of Luigi or I~ewis. -
Influence of Temperature and Water Content on Microstructure Evolution
Contributions to Mineralogy and Petrology (2018) 173:5 https://doi.org/10.1007/s00410-017-1429-y ORIGINAL PAPER Synthesis of monticellite–forsterite and merwinite–forsterite symplectites in the CaO–MgO–SiO2 model system: influence of temperature and water content on microstructure evolution P. Remmert1 · W. Heinrich1 · B. Wunder1 · L. Morales1 · R. Wirth1 · D. Rhede1 · R. Abart2 Received: 17 September 2017 / Accepted: 28 November 2017 / Published online: 21 December 2017 © The Author(s) 2018. This article is an open access publication Abstract Homogeneous single crystals of synthetic monticellite with the composition Ca0.88Mg1.12SiO4 (Mtc I) were annealed in a ◦ piston-cylinder apparatus at temperatures between 1000 and 1200 C , pressures of 1.0–1.4 GPa, for run durations from 10 min to 24 h and applying bulk water contents ranging from 0.0 to 0.5 wt% of the total charge. At these conditions, Mtc I breaks down to a fine-grained, symplectic intergrowth. Thereby, two types of symplectites are produced: a first symplectite type (Sy I) is represented by an aggregate of rod-shaped forsterite immersed in a matrix of monticellite with end-member composition (Mtc II), and a second symplectite type (Sy II) takes the form of a lamellar merwinite–forsterite intergrowth. Both symplectites may form simultaneously, where the formation of Sy I is favoured by the presence of water. Sy I is meta- stable with respect to Sy II and is successively replaced by the latter. For both symplectite types, the characteristic spacing of the symplectite phases is independent of run duration and is only weeakly influenced by the water content, but it is strongly ◦ ◦ ◦ temperature dependent. -
Siwaqaite, Ca6al2(Cro4)3(OH)12×26H2O, a New Mineral of The
American Mineralogist, Volume 105, pages 409–421, 2020 Siwaqaite, Ca6Al2(CrO4)3(OH)12·26H2O, a new mineral of the ettringite group from the pyrometamorphic Daba-Siwaqa complex, Jordan Rafał JuRoszek1,*, BilJana kRügeR2, iRina galuskina1, Hannes kRügeR2, YevgenY vapnik3, 1 and evgenY galuskin 1Institute of Earth Sciences, Faculty of Natural Sciences, University of Silesia, Będzińska 60, 41-205 Sosnowiec, Poland 2Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria 3Department of Geological and Environmental Sciences, Ben-Gurion University of the Negev, POB 653, Beer-Sheva 84105, Israel aBstRact A new mineral, siwaqaite, ideally Ca6Al2(CrO4)3(OH)12·26H2O [P31c, Z = 2, a = 11.3640(2) Å, c = 21.4485(2) Å, V = 2398.78(9) Å3], a member of the ettringite group, was discovered in thin veins and small cavities within the spurrite marble at the North Siwaqa complex, Lisdan-Siwaqa Fault, Hashem region, Jordan. This complex belongs to the widespread pyrometamorphic rock of the Hatrurim Com- plex. The spurrite marble is mainly composed of calcite, fluorapatite, and brownmillerite. Siwaqaite occurs with calcite and minerals of the baryte-hashemite series. It forms hexagonal prismatic crystals up to 250 mm in size, but most common are grain aggregates. Siwaqaite exhibits a canary yellow color and a yellowish-gray streak. The mineral is transparent and has a vitreous luster. It shows perfect cleav- age on (1010). Parting or twinning is not observed. The calculated density of siwaqaite is 1.819 g/cm3. Siwaqaite is optically uniaxial (–) with w = 1.512(2), e = 1.502(2) (589 nm), and non-pleochroic. -
SODIUM BICARBONATE (NAHCOLITE) from COLORADOOIL SHALE1 Tbr-R-Enrr-2
SODIUM BICARBONATE (NAHCOLITE) FROM COLORADOOIL SHALE1 TBr-r-Enrr-2 Assrnact Sodium bicarbonate (nahcolite) was found in the high-grade oil-shale zone of tfre Para- chute Creek member of the Eocene Green River formation in ttre underground development openings of ttre Bureau of Mines Oil-Shale Demonstration Mine at Anvil Points, 10 miles west of Rifle, Colo. It occurs as concretions varying up to five feet in diameter and as layers up to four inches thick, intercalated between rich oil-shale beds. It is suggested tlat the concretions were formed while the ooze, which had been deposited in the bottom of the former Uinta Lake, was still soft and plastic. INrnorucrrorq Natural sodium bicarbonate (NaHCOa) was reported first by P. Wal- thera from Little Magadi dry lake, in British East Africa, but no con- flmatory evidence was given. F. A. Bannister,a who reported natural sodium bicarbonate in an efforescencefrom an old Roman underground conduit from hot springs at Stufe de Nerone, near Naples, gave the min- eral the name "nahcolite." Later the mineral was reported by E. Quer- cighs as an incrustation in a lava grotto, apparently mixed with thenar- dite and halite. Large quantities of nahcolite were found in a well core- dritled below the central salt crust of Searles Lake and described by William F. Foshag.6 The presenceof saline phasesin the eastern part of the Uinta Basin in the high-grade oil-shale facies of the Parachute Creek member of the Eocene Green Eiver formation was noted by W. H. Bradley.T He states that ellipsoidal cavities whose major axes range from a fraction of an inch to more than five feet in length contained molds of radial aggregates of a saline mineral that could not be determined becauseof the complex intergrowth of the crystal molds. -
Raman Spectroscopy and Single-Crystal High-Temperature Investigations of Bentorite, Ca6cr2(SO4)3(OH)12·26H2O
minerals Article Raman Spectroscopy and Single-Crystal High-Temperature Investigations of Bentorite, Ca6Cr2(SO4)3(OH)12·26H2O Rafał Juroszek 1,* , Biljana Krüger 2 , Irina Galuskina 1 , Hannes Krüger 2 , Martina Tribus 2 and Christian Kürsten 2 1 Institute of Earth Sciences, Faculty of Natural Sciences, University of Silesia, B˛edzi´nska60, 41-205 Sosnowiec, Poland; [email protected] 2 Institute of Mineralogy and Petrography, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria; [email protected] (B.K.); [email protected] (H.K.); [email protected] (M.T.); [email protected] (C.K.) * Correspondence: [email protected]; Tel.: +48-516-491-438 Received: 28 November 2019; Accepted: 27 December 2019; Published: 30 December 2019 Abstract: The crystal structure of bentorite, ideally Ca Cr (SO ) (OH) 26H O, a Cr3+ analogue of 6 2 4 3 12· 2 ettringite, is for the first time investigated using X-ray single crystal diffraction. Bentorite crystals of suitable quality were found in the Arad Stone Quarry within the pyrometamorphic rock of the Hatrurim Complex (Mottled Zone). The preliminary semi-quantitative data on the bentorite composition obtained by SEM-EDS show that the average Cr/(Cr + Al) ratio of this sample is >0.8. Bentorite crystallizes in space group P31c, with a = b = 11.1927(5) Å, c =21.7121(10) Å, V = 2355.60(18) Å3, and Z = 2. The crystal structure is refined, including the hydrogen atom positions, to an agreement index R1 = 3.88%. The bentorite crystal chemical formula is Ca (Cr Al ) [(SO ) (CO ) ] (OH) ~25.75H O. -
Carbonation of Borehole Seals: Comparing Evidence from Short-Term Laboratory Experiments and Long-Term Natural Analogues Christopher A
Carbonation of borehole seals: Comparing evidence from short-term laboratory experiments and long-term natural analogues Christopher A. Rochelle* and Antoni E. Milodowski British Geological Survey, Environmental Science Centre, Nicker Hill, Keyworth, Nottingham, NG12 5GG, UK * Corresponding author: [email protected], tel +44 115 9363259, fax +44 115 363200 Abstract It is crucial that the engineered seals of boreholes in the vicinity of a deep storage facility remain effective for considerable timescales if the long-term geological containment of stored CO2 is to be effective. These timescales extend beyond those achievable by laboratory experiments or industrial experience. Study of the carbonation of natural Ca silicate hydrate (CSH) phases provides a useful insight into the alteration processes and evolution of cement phases over long-timescales more comparable with those considered in performance assessments. Samples from two such natural analogues in Northern Ireland have been compared with samples from laboratory experiments on the carbonation of Portland cement. Samples showed similar carbonation reaction processes even though the natural and experimental samples underwent carbonation under very different conditions and timescales. These included conversion of the CSH phases to CaCO3 and SiO2, and the formation of a well-defined reaction front. In laboratory experiments the reaction front is associated with localised Ca migration, localised matrix porosity increase, and localised shrinkage of the cement matrix with concomitant cracking. Behind the reaction front is a zone of CaCO3 precipitation that partly seals porosity. A broader and more porous/permeable reaction zone was created in the laboratory experiments compared to the natural samples, and it is possible that short-term experiments might not fully replicate slower, longer-term processes. -
BREDIGITE, LARNITE and ? DICALCIUM SILICATES from MARBLE CANYON Tnolras E
THE AMERICAN MINERALOGIST, VOL. 51, NOVEMBER_DECEMBER, 1966 BREDIGITE, LARNITE AND ? DICALCIUM SILICATES FROM MARBLE CANYON Tnolras E. Bnrocn, DepartmentoJ Geosciences,Texas T echnological College, Lubbo ck, T enas.r Alstnact The a' (bredigite), p (larnite) and 7 (unnamed) forms of dicalcium silicate (CarSiOr) occur together in the contact zone around a syenite-monzonite intrusion in Marble Canyon. Bredigite, larnite and 7 have consistant crystallographic orientations when they occur together. These relationships reflect the crystallographic direction in which the reorganiza- tion occurs when transformation from one form to another takes place. INrnooucrroN Two polymorphic forms of dicalcium silicate (CazSiOD have been de- scribed as naturally occurring minerals by Tilley (1929) and Tilley and Vincent (1948).The mineralswere found in a contact zonein Larne, Ire- Iand and given the names larnite and bredigite. Until 1964,no natural occurrencesof theseminerals had been reported from any locality in the United States. In 1963, three polymorphic forms of CazSiOawere found in the contact zone around a syenite-monzonite intrusion in 1\4arbleCavon. LocarroN AND SETTTNG Marble Canyon is in the east rim of the Diablo Plateau in Culberson County, Trans-PecosTexas, 30 miles north of the town of Van Horn and 2 miles west of State Highway 54. The canyon is about a mile long and terminates upstream in an elongate amphitheater roughly a mile and a half Iong and half a mile wide. In the center of this elongate amphitheater is an elliptical outcrop of five different types of igneous rock that are arranged in a concentric pattern. From the center out they are: (1) a coarse-grained syenite; (2) a coarse-grained green monzonitel (3) a medium-grained gray monzonite; (4) a discontinuous narrow border of olivine gabbro; and (5) small rhyolite dikes which cut the other rock types. -
Magnesioferrite-Olivine Rock and Monticellite-Bearing Dunite from the Iwanai-Dake Alpine-Type Peridotite Mass in the Kamuikotan Structural Belt, Hokkaido, Japan
J. Japan. Assoc. Min, Petr. Econ. Geol. 77, 23-31. 1982 Magnesioferrite-olivine rock and monticellite-bearing dunite from the Iwanai-dake alpine-type peridotite mass in the Kamuikotan structural belt, Hokkaido, Japan JITSUYA NAGATA Department of Earth Sciences, Kanazawa University, Kanazawa 920, Japan Magnesioferrite, monticellite, perovskite and calcium brittle mica occur in the alpine- type Iwanai-dake peridotite mass in the Kamuikotan structural belt, Hokkaido. These minerals were not primary phases, but were produced through metasomatic processes at a later stage of the granulite facies equilibration. Introduction Magnesioferrite, monticellite, perovskite and calcium brittle mica were found in the Iwanai-dake peridotite mass, an alpine-type intrusion in Hokkaido. As these minerals have not been described in alpine-type peri dotite, their modes of occurrence, chemis tries and paragenetic relations will be described in this paper. The Iwani-dake mass (Fig. 1) is intrud- ed in the Kamuikotan structural belt which is a melange zone consisting of high-pressure metamorphic rocks, low-pressure metamor Fig. 1. Locality of the Iwanai-dake peridotite phic rocks derived from an ophiolitic suite, mass, Hokkaido. and ultramafic rocks (Banno et al., 1978; Asahina and Komatsu, 1979). The Iwanai- ing to Arai (1978), equilibrium temperature dake mass is composed largely of dunite and of ultramafic rocks is estimated to 600 to harzburgite and is almost free from ser 700°C using the olivine-Ca-rich clinopyroxene pentinization (Bamba, 1955; Kato, 1978; geothermometer and olivine-spinel geother Niida and Kato, 1978; Arai, 1978). Gener mometer. ally, dunite and harzburgite form layered structures. Small amounts of chromitite Mode of occurrence, petrography and are also present. -
Salt Crystallization Temperatures in Searles Lake, California!
Mineral. Soc. Amer. Spec. Pap. 3, 257-259 (1970). SALT CRYSTALLIZATION TEMPERATURES IN SEARLES LAKE, CALIFORNIA! GEORGE 1. SMITH, U.S. Geological Survey, Menlo Park, California 94025 2 IRVING FRIEDMAN, AND SADAO MATSU0 , U.S. Geological Survey, Denver, Colorado ABSTRACT The DIH ratios in natural samples of borax, gaylussite, nahcolite and trona were compared with minerals synthesized in the laboratory to deduce temperatures of crystallization in Searles Lake. During most of the Early Holocene, trona in the Upper Salt was deposited during warm summers, average 32°C, similar to the present. Crystallization temperatures of the Middle Wisconsin Lower Salt inferred from DIH ratios are in the range _12° to +8°C; by consideration of phase rela- tions these are assigned to winter crystallization. Winter temperatures much colder than those of the present are inferred for the upper and lower thirds of this Lower Salt unit; summer temperatures for these units inferred from mineral as- semblages are also lower than those of the present. A more complete description of the method, data and results will be published elsewhere. INTRODUCTION are therefore considered to have crystallized well above Searles Lake, which is dry today, was one of a chain of 20°C, and assemblages lacking burkeite are considered to large lakes that formed in the Great Basin segment of have formed at lower temperature. Similarly, assemblages southeast California during pluvial periods of late Quater- that contain nahcolite, borax, thenardite, and mirabilite, nary time (Gale, 1914; Flint and Gale, 1958; Smith, 1968). whose solubilities are also greatly affected by temperature, The number of lakes in the chain, and the size of the last are used to estimate crystallization temperatures. -
Grossite and Hibonite Bearing Refractory Inclusions in the CO3.1 Chondrite Miller Range 090019. D. K. Ross1 and J. I. Simon2, 1U
49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083) 2559.pdf Grossite and Hibonite Bearing Refractory Inclusions in the CO3.1 Chondrite Miller Range 090019. D. K. Ross1 and J. I. Simon2, 1University of Texas El Paso/Jacobs Technology/NASA-JSC-ARES (2224 Bay Area Blvd. Houston TX 77058, USA ([email protected]), 2NASA-Johnson Space Center-ARES ([email protected]). Introduction: We have characterized 142 refract- finer grained particles with substantial porosity. Ongo- ory objects by EDS hyperspectral X-ray mapping in the ing reaction with nebular gases produces down-temper- CO3.1 chondrite MIL 090019-13. These include 127 ature phases partially replacing earlier formed phases Ca-Al rich inclusions (CAIs), 14 amoeboidal olivine ag- and infilling porosity, leading to densified objects. gregates (AOAs) and one Al-rich chondrule. These data Most CAIs are not fully equilibrated, but exhibit miner- are being used to reveal the mineralogy, texture and alogy reflecting a considerable range of temperature, bulk composition of these inclusions, and to identify ob- with relict phases. Hibonite is typically intergrown with, jects that represent endmembers within cogenetic popu- and partially replaced by spinel, violating the predicted lations of primitive inclusions, which will be further in- crystallization order from thermodynamic calcula- vestigated by future isotopic studies. Previous work re- tions[3], in which melilite should precede spinel crystal- lated to these refractory inclusions in this chondrite also lization. appear in [1] and [2]. Twenty six inclusions are hibonite-bearing, 18 are grossite-bearing and one inclusion is corundum-rich. In seven of these inclusions, grossite and hibonite coexist. -
List of Abbreviations
List of Abbreviations Ab albite Cbz chabazite Fa fayalite Acm acmite Cc chalcocite Fac ferroactinolite Act actinolite Ccl chrysocolla Fcp ferrocarpholite Adr andradite Ccn cancrinite Fed ferroedenite Agt aegirine-augite Ccp chalcopyrite Flt fluorite Ak akermanite Cel celadonite Fo forsterite Alm almandine Cen clinoenstatite Fpa ferropargasite Aln allanite Cfs clinoferrosilite Fs ferrosilite ( ortho) Als aluminosilicate Chl chlorite Fst fassite Am amphibole Chn chondrodite Fts ferrotscher- An anorthite Chr chromite makite And andalusite Chu clinohumite Gbs gibbsite Anh anhydrite Cld chloritoid Ged gedrite Ank ankerite Cls celestite Gh gehlenite Anl analcite Cp carpholite Gln glaucophane Ann annite Cpx Ca clinopyroxene Glt glauconite Ant anatase Crd cordierite Gn galena Ap apatite ern carnegieite Gp gypsum Apo apophyllite Crn corundum Gr graphite Apy arsenopyrite Crs cristroballite Grs grossular Arf arfvedsonite Cs coesite Grt garnet Arg aragonite Cst cassiterite Gru grunerite Atg antigorite Ctl chrysotile Gt goethite Ath anthophyllite Cum cummingtonite Hbl hornblende Aug augite Cv covellite He hercynite Ax axinite Czo clinozoisite Hd hedenbergite Bhm boehmite Dg diginite Hem hematite Bn bornite Di diopside Hl halite Brc brucite Dia diamond Hs hastingsite Brk brookite Dol dolomite Hu humite Brl beryl Drv dravite Hul heulandite Brt barite Dsp diaspore Hyn haiiyne Bst bustamite Eck eckermannite Ill illite Bt biotite Ed edenite Ilm ilmenite Cal calcite Elb elbaite Jd jadeite Cam Ca clinoamphi- En enstatite ( ortho) Jh johannsenite bole Ep epidote -
Origin and Resources of World Oil Shale Deposits - John R
COAL, OIL SHALE, NATURAL BITUMEN, HEAVY OIL AND PEAT – Vol. II - Origin and Resources of World Oil Shale Deposits - John R. Dyni ORIGIN AND RESOURCES OF WORLD OIL SHALE DEPOSITS John R. Dyni US Geological Survey, Denver, USA Keywords: Algae, Alum Shale, Australia, bacteria, bitumen, bituminite, Botryococcus, Brazil, Canada, cannel coal, China, depositional environments, destructive distillation, Devonian oil shale, Estonia, Fischer assay, Fushun deposit, Green River Formation, hydroretorting, Iratí Formation, Israel, Jordan, kukersite, lamosite, Maoming deposit, marinite, metals, mineralogy, oil shale, origin of oil shale, types of oil shale, organic matter, retort, Russia, solid hydrocarbons, sulfate reduction, Sweden, tasmanite, Tasmanites, thermal maturity, torbanite, uranium, world resources. Contents 1. Introduction 2. Definition of Oil Shale 3. Origin of Organic Matter 4. Oil Shale Types 5. Thermal Maturity 6. Recoverable Resources 7. Determining the Grade of Oil Shale 8. Resource Evaluation 9. Descriptions of Selected Deposits 9.1 Australia 9.2 Brazil 9.2.1 Paraiba Valley 9.2.2 Irati Formation 9.3 Canada 9.4 China 9.4.1 Fushun 9.4.2 Maoming 9.5 Estonia 9.6 Israel 9.7 Jordan 9.8 Russia 9.9 SwedenUNESCO – EOLSS 9.10 United States 9.10.1 Green RiverSAMPLE Formation CHAPTERS 9.10.2 Eastern Devonian Oil Shale 10. World Resources 11. Future of Oil Shale Acknowledgments Glossary Bibliography Biographical Sketch Summary ©Encyclopedia of Life Support Systems (EOLSS) COAL, OIL SHALE, NATURAL BITUMEN, HEAVY OIL AND PEAT – Vol. II - Origin and Resources of World Oil Shale Deposits - John R. Dyni Oil shale is a fine-grained organic-rich sedimentary rock that can produce substantial amounts of oil and combustible gas upon destructive distillation.