Supplementary Table 1

Total Page:16

File Type:pdf, Size:1020Kb

Supplementary Table 1 Supplementary Table 1. Compositional groups, typical sample numbers and location with their bulk compositional, mineralogical and petrographic characteristics at different metamorphic grades. Sample #s, Mineral assemblage, Compositio N/E Traverse, Texture Metamorphic Bulk Chemical mode nal GPS and grade Characteristics and Group coordinates other comments mineral chemistry Ms-Chl-Qtz-Ilm-Mag-Gr ± Kfs ± Pl Mode: (Qtz 35-42%, Ms 30 - 33%, Chl 25 - 30%, Pl 5-7%). #1/00, E, Lithology: Chlorite quartz phyllite (minor white 27 o11.268, mica), white mica quartz phyllite (minor chlorite) /88 o38.581 Two compositional and chlorite bearing quartzite. Millimeter to centimeter groups (one richer in scale banding into M- Al 2O3 ~25 wt.%, Muscovite: domain (mica + chlorite Chlorite Normal #187/01, another ~20 Wt.%). rich), grain size 2 - 20 m 187/3, Rocks richer in Paragonite 5%, Pyrophyllite 19%, Celadonite 12%, and Q - domain (quartz - 187/3/ CHAKRA Al 2O3 are relatively Fe-celadonite 13%. feldspar rich), grain size 10 , N, GPS not less ferruginous (see - 50 µm. known Fig 3). Chlorite: XMg (Mg/(Mg+Fe(tot)) = 0.37 - 0.41. Plagioclase: XAn = 0.03 #ID/00,E, Ms-Chl-Qtz-Bt - Pl ± Ilm ± Tur ± Gr 27 o11.268, /88 o38.581 Chl - Qtz - Ms - Ilm -Gr - Tur - Bt - Pl #2/00, E, Two subgroups - 27 o11.465, high Al, low Fe (18 o /88 38.650 - 24 wt% Al 2O3, - Mode: (Qtz 35-42%, Ms 30 - 33%, Bt 15 - 18%, Chl 4.5-5 wt% Fe 2O3) 10 - 12%, Pl 5-7%). Pervasive foliation defined #3/00, E, and low Al, high Fe by biotite, white mica, o 27 11.465, (14.5 - 17 wt% chlorite and occasional o /88 38.692 Al 2O3, 6.0 - 8.0 wt% Muscovite: ilmenite (S 2) almost parallel Fe 2O3). to compositional banding #4/00, E, Some with high Paragonite 10 -15%, Pyrophyllite 22 - 28%, (S 0). S 2 is crenulated to S 3 27 o11.484, MnO (0.37 - 0.59 Celadonite 6 -9%, Fe-celadonite 6-14%. defned by new generation Biotite Normal o /88 38.858 wt%). SiO 2 variable of biotite, ilmenite and indicating Biotite: elongated quartz in Q - #167/01, N, interbanding of domains. Some coarser o 27 26.092, variable amounts of XMg = 0.38, X Fe = 0.45, X Ti = 0.03, X (AlVi) = 0.14. biotite, chlorite as well as /88 o30.888 psammitic material, plagioclase cross cut all TiO 2 relatively Chlorite: foliations and appear to be #176/01,N, constant (0.55 - 0.8 post-tectonic. o 27 24.809, wt% for most XMg (Mg/(Mg+Fe(tot)) = 0.45. /88 o30.935 samples). Plag: #170/01,N, o 27 24.809, XAn = 0.03 /88 o30.925 Chlorite - quartz - plagioclase ± muscovite Muscovite: Paragonite 7 - 12%, Pyrophyllite 16 - 33%, #1/00/A, E, Celadonite 11 - 13%, Fe-celadonite 12%. Foliation defined by chlorite Magnesian 27 o11.268, and white mica; crenulation (Normal - /88 o38.581 MgO ~ 5 wt%. Chlorite: Biotite by second generation white biotite) mica. XMg (Mg/(Mg+Fe(tot)) = 0.65. Plagioclase: XAn = 0.1 Ms - Chl - Qtz - Pl - Grt - Mag - Ilm - Gr. Garnet: Concentric growth zoned with Mn and Ca decreasing to rim compensated by increase of Fe and Mg. Core: Sps 50 Alm 34 Prp 3Grs 13 150 - 200 µm euhedral garnet porphyroblasts set in Rim: external S 2 fabric defined Sps 20 Alm 63 Prp 07 Grs 10 by white mica. Elongate quartz and opaque Muscovite: inclusions near core of garnet define an internal Mn-rich # 1C/00/3, E MnO ~ 0.4 wt%, ~ Paragonite 14%, Pyrophyllite 15%, Celadonite 6%, fabric (? S ) at high angles (Normal + 27 o11.288, 10 x other bulk 1 Biotite Fe-celadonite 15%. to the external fabric. Grt) /88 o38.619 compositions. Coarse plagioclase as well Chlorite: as later generation of mica and chlorite cut across main XMg (Mg/(Mg+Fe(tot)) = 0.47; Mn-rich with 0.5 - foliation. Quartz is coarse, 0.6 wt% MnO (= 10x other rocks). polygonal in Q-domains and elongate in M-domains. Plagioclase porphyroblasts reverse zoned, unlike in other rocks, from An 26 (core) - An 10 (rim). Ms - Qtz - Chl - Bt ± Pl - Ilm ± Grt ± Gr Mode: (Qtz 26-30%, Ms 35-40%, Bt 8-15%, Chl 8%, Grt 1-3%, Pl 5-8%) Garnet preferentially Garnet: Concentrically zoned, typical core: develops in graphitic Alm Prp Grs Sps , typical rim: 72 05 06 17 schists. S2 defined by Alm Prp Grs Sps . Total range found: Alm 81 05 04 10 68- Muscovite, chlorite and Prp Grs Sps . In rocks without plagioclase, #8/00, E, 80 4-16 6-16 2-17 biotite wrap around garnet garnet is more calcic: 27 o11.616, porphyroblasts. Marked Low alumina as well Alm Prp Grs Sps . /88 o39.131; 65-68 03 18-21 14 decrease in modal Normal as high alumina abundance of chlorite in compositions Biotite at contact with garnet: X = 0.28, X = #158/01, N, Mg Fe garnet rich areas. S often represented; some 0.47, X = 0.01, X = 0.24. 2 27 o27.711, Ti (AlVI) forms sigmoidal inclusion Mn rich and Mg rich /88 o31.400 trails in garnet, some Garnet bulk compositions Ilmenite included in garnet has higher Mn content garnets include an inner found without (= 5 mol% pyrophanite vs. 3mol% in matrix). trail of S that is straight profound effects on 1 and truncated by S . mineral assemblages Chlorite: XMg = 0.36 - 0.39, lower than in lower 2 #24/99/1, N, Aluminous, at these grades. grades. 27 o27.292´, Magnesian bulk high Fe /88 o31.63 compositions (e.g. #19/99) Muscovite: have lower modal abundance of garnet Paragonite 11%, Pyrophyllite 21%, Celadonite 6%, compared to Fe-rich (e.g. Fe-celadonite 6%. #24/99) samples. Plagioclase: XAn = 0.1 Ms - Cld - Qtz - Chl - Bt - Ilm ± Gr ± Grt Chloritoid porphyroblasts Mode: (Qtz 35-40%, Cld 12 - 16%, Grt 4-8%, Chl 8 Similar in Mn and may be aligned along S or #7/00/R4 - 16%, Ms 20 - 22%, Bt 8-10%, Pl 6-10%). 2 even lower in Al S foliation. Ilmenite is & 7/00/R/6, E, 3 content to garnet often included in chloritoid. 27 o11.616, Cld: bearing rocks from In one case chloritoid and Ferruginous /88 o39.131 the same outcrop garnet occur in the same (Normal + X = 0.1 Garnet (e.g. #8/00). Fe/Mg Mg thin section but in different Chltd) ratio - higher Fe domains - chloritoid occurs #135/01, E, Chlorite: contents - favor in more muscovite rich GPS not appearance of domains. There is a single known X = 0.25 chloritoid. Mg chloritoid inclusion in a garnet in #135/01. Biotite: X Mg = 0.39, X Ti = 0.04, X (AlVI) = 0.18. Chl - Qtz - Grt - Pl - Bt - Ap - Ilm Garnet: Alm 80 Prp 12 Grs 04 Sps 04 , even richer in almandine (82) Low at the rim. Chlorite - garnet - #10/00, E, Potassic plagioclase rich rock with 27 o11.628, (semi - Biotite: chlorite and biotite defining /88 o39.459; Garnet pelite) S foliation. Euhedral garnet 2 (Normal - X = 0.28, X = 0.55, X = 0.03, X = 0.14. overprints, and sometimes Mg Fe Ti (AlVI) Musc deflects, this foliation. Chlorite: XMg = 0.36. Plagioclase: XAn = 0.15 - 0.17. Ms - Qtz -St - Pl - Bt - Ilm - Grt Muscovite and biotite define foliation (S2). Mode: (Qtz 35 - 44%, Ms 15 - 17%, Bt 18 -22%, St Sigmoidal inclusion trails of 9 - 11%, Grt 5-10%, Pl 5 - 10%). S2, including ilmenites, within staurolite and garnet. Garnet: Foliation wraps around porphyroblasts. Core: Alm 63 Prp 12 Grs 08 Sps 17 , with well preserved growth zoning. Increase of Mn content at the very rim. #17/00, E, Equivalent of low Staurolite Normal 27 o12.064, alumina pelites from Muscovite: /88 o41.397 lower grades. Paragonite 17%, Pyrophyllite 12%, Celadonite 5%, Fe-celadonite 10%. Biotite: XMg = 0.4, X Fe = 0.42, X Ti = 0.02, X (AlVI) = 0.16. Staurolite: XFe = 0.78. Ms -Bt -Grt -St - Ky - fibrolite -Grt - Ilm – Qtz ± Cld, secondary Chl. Some locations contain abundant and strongly zoned Tur. Garnet: Core: Alm 83 Prp 09 Grs 06 Sps 02 , distinctly poorer in Mn and only weakly zoned Muscovite and biotite (XAlm ~ Xprp ~ 0.02). define S 2, garnet and staurolite include sigmoidal Muscovite: trails of S 2, kyanite is coarse prismatic. Paragonite 18%, Celadonite 4.5%, Rare chloritoid inclusion in Fe-celadonite 7.5%. garnet coexisting with Aluminous staurolite. (Normal + #11/00, E, Staurolite Biotite: Tourmaline can define kyanite) folded inclusion trails in XMg = 0.34, X Fe = 0.45, X Ti = 0.05, X (AlVI) = 0.16. staurolite sometimes. Plagioclase: Fibrolite often surrounds garnet, biotite with ilmenite, XAn = 0.2. can be folded into crenulations occasionally. Staurolite: XFe = 0.82 - 0.86 (included chloritoid has X Fe = 0.85). Ms - Bt - Qtz - Pl - Grt - Ilm Garnet: Abundant garnet and Exceptionally rich in Sps and Grs in plagioclase; in spite of high CaO = 3.7 wt% Core: Al as well as Zn content, Calcic #14/00, E, compared to general Staurolite does not appear, (Normal - 27 o12.174, Staurolite range of 0.15 - 0.52 Alm Prp Grs Sps , indicating that its Staurolite) /88 o41.026 50 09 14 27 %. with well preserved growth zoning. appearance is controlled by Ca (e.g. Spear and others Plagioclase rich in An: 1995). XAn = 0.34 Ms - Qtz -St - Pl - Bt - Ilm - Grt Garnet: Core: Alm 73 Prp 05 Grs 13 Sps 09 , Rim: Alm 84 Prp 10 Grs 5.5 Sps 0.5 . Muscovite: #15/00, E, Mn - poor 27 o12.157, Paragonite 17%, Pyrophyllite 12%, Celadonite 5%, (Normal, /88 o41.137 Fe-celadonite 10%.
Recommended publications
  • PARAGONITE PSEUDOMORPHS AFTER KYANITE from TURKEY HEAVEN MOUNTAIN, CLEBURNE COUNTY, ALABAMA1 Tnonnron L. Noarnnnu, Geological Su
    THE AMERICAN MINERALOGIST, VOL, 50, MAY_JIJ'}IE, 1965 PARAGONITE PSEUDOMORPHS AFTER KYANITE FROM TURKEY HEAVEN MOUNTAIN, CLEBURNE COUNTY, ALABAMA1 TnonNroN L. Noarnnnu, GeologicalSuraey of Alabama, Uniaersity, Alabama. ABSTRACT Paragonite pseudomorphs after kyanite have been found in the Turkey Heaven Moun- tain kyanite prospects. The pseudomorphs range in size from microscopic grains to mega- scopic prisms, which resemble andalusite crystals Optical, o-ray and petrographic studies indicate direct hysterogenic paragonite alteration of the kyanite. INrnolucrroN An investigationof kyanite prospectsin Sections22 and29,T.17 5., R. 11 E., at Turkey Heaven Mountain, Cleburne County, Alabama, discloseda unique mineral occurrence.The mineral assemblageincludes hysterogenicparagonite pseudomorphsafter kyanite, which resemble andalusite.The geneticphysicochemical parameters are consideredas a function of retrogrademetamorphism within a restrictive water environ- ment. GBor-ocrc SB:rrrNc The Turkey Heaven Mountain areais underlain by two metamorphic rock units: 1) the WedoweeFormation, a highly resistantgraphite-mica schist,and 2) a unit of the Ashland Mica Schist,an extensivelyweathered garnet-muscovite schist. Fresh rock exposuresindicate a retrograde metamorphic cycle from an almandine-amphibolite facies to a green- schist facies. At the crest of Turkey Heaven Mountain, the Wedowee Formation over-liesthe Ashland Mica Schist.The resistantgraphite-mica schist of the WedoweeFormation and associatedquartz veins contribute to the physiographic configuration of the area. The generalregional strike in the Alabama crystalline belt is about N. 45o E., and the dip is generally southeast.The crystalline area has undergoneprimary deformationfrom the stressesapplied generallyfrom the southeast,which producedisoclinal folding and thrust faulting to the northwest. Geologic studies at Turkey Heaven Mountain indicate a secondperiod of deformation in which the stressdirection can be ex- pressedaS a northeast shear couple that formed nonplanar, non-cylin- drical left lateral drag folds.
    [Show full text]
  • Studies of Celadonite and Glauconite
    Studies of Celadonite and Glauconite GEOLOGICAL SURVEY PROFESSIONAL PAPER 614-F Studies of Celadonite and Glauconite By MARGARET D. FOSTER SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 614-F A study of the compositional relations between celadonites and glauconites and an interpretation of the composition of glauconites UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1969 UNITED STATES DEPARTMENT OF THE INTERIOR WALTER J. HIGKEL, Secretary GEOLOGICAL SURVEY William T. Pecora, Director For sale by the Superintendent of Documents, U.S- Government Printing Office Washington, D.C. 20402 - Price 40 cents (paper cover) CONTENTS Page Abstract.-_ ____-____-_--__-_-___--______-__-_______ Fl Interpretation of glauconite coniposition___-___________ F13 Introduction.______________________________________ 1 Relation between trivalent iron and octahedral aluminurn____________________________________ 13 Selection of analyses and calculation of atomic ratios___ 2 The Fe+3 :Fe+2 ratio_______________________ 13 Relation between the composition of celadonites and Relation between iron and potassium____________ 14 glauconites_ _ ___________________________________ 3 Fixation of potassium___________________________ 14 High potassium celadonites and glauconites-_______ 7 Deficiency in potassium content-_________________ 14 Relation between glauconite composition and geo­ Low potassium celadonites and glauconites_________ logic age_____________________________________ 15 Relation between Si, R+2 (VI), Al(VI), and R+3 (VI)_
    [Show full text]
  • Duration of Hydrothermal Activity at Steamboat Springs, Nevada, from Ages of Spatially Associated Volcanic Rocks
    Duration of Hydrothermal Activity at Steamboat Springs, Nevada, From Ages of Spatially Associated Volcanic Rocks GEOLOGIC AiL SURVEY PROFESSIONAL PAPER 458-D Duration of Hydrothermal Activity at Steamboat Springs, Nevada, From Ages of Spatially Associated Volcanic Rocks By M. L. SILBERMAN, D. E. WHITE, T. E. C. KEITH, and R. D. DOCKTER GEOLOGY AND GEOCHEMISTRY OF THE STEAMBOAT SPRINGS AREA, NEVADA GEOLOGICAL SURVEY PROFESSIONAL PAPER 458-D UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1979 UNITED STATES DEPARTMENT OF THE INTERIOR CECIL D. ANDRUS, Secretary GEOLOGICAL SURVEY H. William Menard, Director Library of Congress Cataloging in Publication Data Main entry under title: Duration of hydrothermal activity at Steamboat Springs, Nevada, from ages of spatially associated volcanic rocks. (Geology and geochemistry of the Steamboat Springs area, Nevada) (United States. Geological Survey. Professional paper ; 45 8-D) Bibliography: p. D13-D14. 1. Geothermal resources-Nevada-Steamboat Springs. 2. Geology- Nevada Steamboat Springs. 3. Potassium-argon dating. I. Silberman, Miles L. II. Series. III. Series: United States. Geological Survey. Professional paper ; 45 8-D. QE75.P9no. 458-D [GB1199.7.N3] 557.3'08s [553] 79-16870 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 Stock Number 024-001-03215-5 CONTENTS Page Abstract __________ _______.._____________ Dl Potassium-argon ages Continued Introduction ______________________________________________ 1 Rhyolite domes______________________
    [Show full text]
  • Experimental Data for High-Temperature Decomposition of Natural Celadonite from Banded Iron Formation
    Chin. J. Geochem. (2015) 34(4):507–514 DOI 10.1007/s11631-015-0066-2 ORIGINAL ARTICLE Experimental data for high-temperature decomposition of natural celadonite from banded iron formation 1 1 1 K. A. Savko • S. M. Piliugin • N. S. Bazikov Received: 5 March 2015 / Revised: 1 May 2015 / Accepted: 6 July 2015 / Published online: 17 July 2015 Ó Science Press, Institute of Geochemistry, CAS and Springer-Verlag Berlin Heidelberg 2015 Abstract Three experiments were set up to evaluate (KMA), Russia. Subalkaline BIF contains widespread conditions for the high-temperature decomposition of riebeckite, aegirine, celadonite, tetraferribiotite, and Al- celadonite from a banded iron formation in an alumina-free free chlorite instead of grunerite, stilpnomelane, minneso- system and identify its decomposition products. It was taite, and greenalite, which are the usual minerals in BIF estimated that at 650 and 750 °C, with a NiNiO buffer and elsewhere. At the KMA iron deposits, BIF with alkali pressure of 3 kbar, celadonite completely decomposes and amphibole were metamorphosed at 370–520 °C and 2–3 the decomposition products were tetraferribiotite, mag- kbar (Savko and Poskryakova 2003). netite and quartz. Under more oxidizing conditions (he- In the KMA, BIF green mica, which is responsible in matite-magnetite buffer instead of NiNiO), ferrous composition to the celadonite with the formula KFe3?(Mg, 2? potassium feldspar sanidine forms instead of magnetite. Fe ) = [Si4O10](OH)2, is quite abundant (Savko and During the celadonite decomposition in oxidizing condi- Poskryakova 2003). Celadonite forms emerald-green scales tions more magnesian and aluminous tetraferribiotite, sizing from a few tenths to 1.5–2 mm, composing up to along with ferrous sanidine, are formed than at reducing 30 %–40 % modal.
    [Show full text]
  • Factors Responsible for Crystal Chemical Variations in The
    American Mineralogist, Volume 95, pages 348–361, 2010 Factors responsible for crystal-chemical variations in the solid solutions from illite to aluminoceladonite and from glauconite to celadonite VICTOR A. DRITS ,1 BELL A B. ZV I A GIN A ,1 DOUGL A S K. MCCA RTY,2,* A N D ALFRE D L. SA LYN 1 1Geological Institute of the Russian Academy of Science, Pyzhevsky per. 7, 119017 Moscow, Russia 2Chevron ETC, 3901 Briarpark, Houston, Texas 77063, U.S.A. AB STR A CT Several finely dispersed low-temperature dioctahedral micas and micaceous minerals that form solid solutions from (Mg,Fe)-free illite to aluminoceladonite via Mg-rich illite, and from Fe3+-rich glauconite to celadonite have been studied by X-ray diffraction and chemical analysis. The samples have 1M and 1Md structures. The transitions from illite to aluminoceladonite and from glauconite to celadonite are accompanied by a consistent decrease in the mica structural-unit thickness (2:1 layer + interlayer) or csinβ. In the first sample series csinβ decreases from 10.024 to 9.898 Å, and in the second from 10.002 to 9.961 Å. To reveal the basic factors responsible for these regularities, struc- tural modeling was carried out to deduce atomic coordinates for 1M dioctahedral mica based on the unit-cell parameters and cation composition. For each sample series, the relationships among csinβ, maximum and mean thicknesses of octahedral and tetrahedral sheets and of the 2:1 layer, interlayer distance, and variations of the tetrahedral rotation angle, α, and the degree of basal surface corruga- tion, ∆Z, have been analyzed in detail.
    [Show full text]
  • 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
    [Show full text]
  • What We Know About Subduction Zones from the Metamorphic Rock Record
    What we know about subduction zones from the metamorphic rock record Sarah Penniston-Dorland University of Maryland Subduction zones are complex We can learn a lot about processes occurring within active subduction zones by analysis of metamorphic rocks exhumed from ancient subduction zones Accreonary prism • Rocks are exhumed from a wide range of different parts of subduction zones. • Exhumed rocks from fossil subduction zones tell us about materials, conditions and processes within subduction zones • They provide complementary information to observations from active subduction systems Tatsumi, 2005 The subduction interface is more complex than we usually draw Mélange (Bebout, and Penniston-Dorland, 2015) Information from exhumed metamorphic rocks 1. Thermal structure The minerals in exhumed rocks of the subducted slab provide information about the thermal structure of subduction zones. 2. Fluids Metamorphism generates fluids. Fossil subduction zones preserve records of fluid-related processes. 3. Rheology and deformation Rocks from fossil subduction zones record deformation histories and provide information about the nature of the interface and the physical properties of rocks at the interface. 4. Geochemical cycling Metamorphism of the subducting slab plays a key role in the cycling of various elements through subduction zones. Thermal structure Equilibrium Thermodynamics provides the basis for estimating P-T conditions using mineral assemblages and compositions Systems act to minimize Gibbs Free Energy (chemical potential energy) Metamorphic facies and tectonic environment SubduconSubducon zone metamorphism zone metamorphism Regional metamorphism during collision Mid-ocean ridge metamorphism Contact metamorphism around plutons Determining P-T conditions from metamorphic rocks Assumption of chemical equilibrium Classic thermobarometry Based on equilibrium reactions for minerals in rocks, uses the compositions of those minerals and their thermodynamic properties e.g.
    [Show full text]
  • Minerals Found in Michigan Listed by County
    Michigan Minerals Listed by Mineral Name Based on MI DEQ GSD Bulletin 6 “Mineralogy of Michigan” Actinolite, Dickinson, Gogebic, Gratiot, and Anthonyite, Houghton County Marquette counties Anthophyllite, Dickinson, and Marquette counties Aegirinaugite, Marquette County Antigorite, Dickinson, and Marquette counties Aegirine, Marquette County Apatite, Baraga, Dickinson, Houghton, Iron, Albite, Dickinson, Gratiot, Houghton, Keweenaw, Kalkaska, Keweenaw, Marquette, and Monroe and Marquette counties counties Algodonite, Baraga, Houghton, Keweenaw, and Aphrosiderite, Gogebic, Iron, and Marquette Ontonagon counties counties Allanite, Gogebic, Iron, and Marquette counties Apophyllite, Houghton, and Keweenaw counties Almandite, Dickinson, Keweenaw, and Marquette Aragonite, Gogebic, Iron, Jackson, Marquette, and counties Monroe counties Alunite, Iron County Arsenopyrite, Marquette, and Menominee counties Analcite, Houghton, Keweenaw, and Ontonagon counties Atacamite, Houghton, Keweenaw, and Ontonagon counties Anatase, Gratiot, Houghton, Keweenaw, Marquette, and Ontonagon counties Augite, Dickinson, Genesee, Gratiot, Houghton, Iron, Keweenaw, Marquette, and Ontonagon counties Andalusite, Iron, and Marquette counties Awarurite, Marquette County Andesine, Keweenaw County Axinite, Gogebic, and Marquette counties Andradite, Dickinson County Azurite, Dickinson, Keweenaw, Marquette, and Anglesite, Marquette County Ontonagon counties Anhydrite, Bay, Berrien, Gratiot, Houghton, Babingtonite, Keweenaw County Isabella, Kalamazoo, Kent, Keweenaw, Macomb, Manistee,
    [Show full text]
  • The Reaction Albite = Jadeite * Quartz Determined Experimentally in The
    American Mineralogkt, Volume 65, pages 129-134, 1980 The reaction albite = jadeite * quartz determinedexperimentally in the range600-1200.c TrMorHy J. B. Hou-eNo Departmentof the GeophysicalSciences, University of Chicago Chicago,Illinois 60637 Abstract The reaction NaAlSirOu+ SiO2 :NaAlSirOs jadeite quaftz high albite has been determinedby direct experimentin the temperaturerange 6fi)-1200"C, and the P- T line can be describedby the equation P: 0.35+ 0.0265?("C) + 0.50kbar The brackets,when comparedwith the gas-apparatusdeterminations of this reactionby Hays and Bell (1973)and by Birch and LeComte (1960),show clearly that pressurecorrections are vanishingly small when the NaCl pressurecell is used with the piston-+ylinder device if pis- ton-out methodsare used.The slope(dP/df : 26.5bar oC-t), io conjunction with tabulated entropiesfor quartz andjadeite, leadsto a value for the entropy ofsynthetic high albite. The disorderingentropy of albite is (14.2+2.4J K-' mol-'), and the enthalpy is (12950=3320J mol-t). The disorderingenthalpy is in excellentagreement with recentcalorimetric measure- ments on Amelia albite and its heat-treatedmodification. The best valuesfrom phase equi- libria for the 298 K, I bar, thermochemicaldata for synthetichigh albite are AJI3I".rt*: -3922170+ 4300J mol-' S&r., o- :221.6 + 2.5J K-t mol-' The lack of curvatureof the reaction in the P-T plane imFlies that high albite doesnot un- dergo ordering down to 600'C, at least within the duration time of the experiments.This is also conflrmed by the X-ray patternsof albites from runs at 600"C. Introduction which high_temperature calorimetry (Holm and The stability of the end-member feldspars is of Kleppa, 1968) predicts a slope of 27.6 bar deg-', as fundamental importance to petrology, yet consid- shown later.
    [Show full text]
  • Minerals of Rockbridge County, Virginia
    VOL. 40 FEBRUARYJMAY 1994 NO. 1 &2 MINERALS OF ROCKBRIDGE COUNTY, VIRGINIA D. Allen Penick, Jr. INTRODUCTION RockbridgeCountyhas agreatdiversityofrocksandminerals.Rocks withinthecountyrangeingeologic agehmPmxnbrianthroughDevonian (01desttoyoungest)covexingatimespanofatleast 1OOOmilIion years. The county liesmostlywithintheVdeyandRiagePhysi~hich~~ 1). Thisprovinceis underlainbysedimentaryrochcomposedof dolostone, limestone, sandstone, andshale. TheexlMlceastempartofRockbridge County is withintheBlueRidge PhysiowhicPro. This areaisrepre sentedbyallthreemajorrocktypes: sedirnentary,igneous, andmetarnorphic. Theseinclu&Qlostone,qdta,inta~s~neandshale,granite, pmdiorite, andunakite. Ingeneral, theol&strocksarefoundin theeastem portion with youngerrocks outcropping in the westernpart of thecounty o%w2). Mininghasplaydan~tpaainthehistoryofRockbridgeCounty. Indians probably were thefirstco1lectorsof localqu~andquartzitefrom which they shapedprojectilepoints. Important deposits of ironore were mined in the 1800s near the towns of Buena Vista, Goshen, Vesuvius, and in Amoldvalley. Other early minesin thecounty -&manganese, waver- tine-marl, tin, niter (saltpeter), lithographiclimestone, silicasand, andcave orryx Thecounty has been prospected for barite, gibbsite (alumina), gold, silver, limonik(ocher),beryl, Ghalerite (zinc), andilmeniteandmtile(tita- nium), but no production has beenreported for t.Quarriesare still producing dolostone.lirnestone, andquartzitefor constructionaggregate andshale forbrickmanufacture. This report describes 102mineralsandnativeelements
    [Show full text]
  • Predictive Mineral Discovery COOPERATIVE RESEARCH CENTRE Scale-Integrated Alteration Studies at Kanowna Belle Dr
    predictive mineral discovery COOPERATIVE RESEARCH CENTRE Scale-Integrated Alteration Studies at Kanowna Belle Dr. Glen Masterman and Scott Halley (Placer Dome Asia Pacific) John Walshe (CSIRO) KB Sulfide Evolution KB Sulfur Isotopes YilgarnSulphurIsotopes_AMG by d34s Kanowna Belle 4 to 20.5 (115) -1 to 4 (415) -4 to -1 (175) 1000 -41.6 to -4 (233) 100 dirty 10 zoned clean Au ppm 1 unclassified 0.1 0.01 -8 -4 0 4 8 δ34S N •Dirty pyrite cores with Au, Te, basemetal & Kanowna Belle; Sulfur Isotope values gangue inclusions 40 KB •As-rich and As-poor growth bands 35 •Clean inclusion-free euhedral pyrite 30 2 km 25 KB overgrowths 20 Regional •Late Au, Te & sulfosalt infill (remobilised or 15 •High Au grades correlate with -ve δ34S values in dirty pyrite cores. new addition??) No. of measurements 10 34 5 •δ S values in zoned pyrite are between -2.8 and 2.9 per mil. 0 •Clean pyrite rims are -2.5 to 0.3 per mil. 0 2 4 6 8 -8 -6 -4 -2 10 -12 -10 δ34S •KB pyrites record a history of oxidised fluids early in the evolution of the deposit gradually becoming swamped by reduced fluids. •Regional δ34S values are clustered around 2 per mil KB Alteration Geochemistry Lowes Shoot Alkali Signature (GDD438) Lowes Shoot Pathfinder Signature (GDD438) KB Regional Alkali Halo Muscovite V-rich + alkali feldspar altered samples Albite KB Muscovite-albite tie line 2 km A plot of K/Al vs. Na/Al molar ratios quantifies alteration Pathfinder elements typically associated with Au include W, Mo, mineralogy.
    [Show full text]
  • Clay Minerals
    CLAY MINERALS CD. Barton United States Department of Agriculture Forest Service, Aiken, South Carolina, U.S.A. A.D. Karathanasis University of Kentucky, Lexington, Kentucky, U.S.A. INTRODUCTION of soil minerals is understandable. Notwithstanding, the prevalence of silicon and oxygen in the phyllosilicate structure is logical. The SiC>4 tetrahedron is the foundation Clay minerals refers to a group of hydrous aluminosili- 2 of all silicate structures. It consists of four O ~~ ions at the cates that predominate the clay-sized (<2 |xm) fraction of apices of a regular tetrahedron coordinated to one Si4+ at soils. These minerals are similar in chemical and structural the center (Fig. 1). An interlocking array of these composition to the primary minerals that originate from tetrahedral connected at three corners in the same plane the Earth's crust; however, transformations in the by shared oxygen anions forms a hexagonal network geometric arrangement of atoms and ions within their called the tetrahedral sheet (2). When external ions bond to structures occur due to weathering. Primary minerals form the tetrahedral sheet they are coordinated to one hydroxyl at elevated temperatures and pressures, and are usually and two oxygen anion groups. An aluminum, magnesium, derived from igneous or metamorphic rocks. Inside the or iron ion typically serves as the coordinating cation and Earth these minerals are relatively stable, but transform- is surrounded by six oxygen atoms or hydroxyl groups ations may occur once exposed to the ambient conditions resulting in an eight-sided building block termed an of the Earth's surface. Although some of the most resistant octohedron (Fig.
    [Show full text]