Epidote As a Primary Component Op Eruptive Rocks
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Download PDF About Minerals Sorted by Mineral Name
MINERALS SORTED BY NAME Here is an alphabetical list of minerals discussed on this site. More information on and photographs of these minerals in Kentucky is available in the book “Rocks and Minerals of Kentucky” (Anderson, 1994). APATITE Crystal system: hexagonal. Fracture: conchoidal. Color: red, brown, white. Hardness: 5.0. Luster: opaque or semitransparent. Specific gravity: 3.1. Apatite, also called cellophane, occurs in peridotites in eastern and western Kentucky. A microcrystalline variety of collophane found in northern Woodford County is dark reddish brown, porous, and occurs in phosphatic beds, lenses, and nodules in the Tanglewood Member of the Lexington Limestone. Some fossils in the Tanglewood Member are coated with phosphate. Beds are generally very thin, but occasionally several feet thick. The Woodford County phosphate beds were mined during the early 1900s near Wallace, Ky. BARITE Crystal system: orthorhombic. Cleavage: often in groups of platy or tabular crystals. Color: usually white, but may be light shades of blue, brown, yellow, or red. Hardness: 3.0 to 3.5. Streak: white. Luster: vitreous to pearly. Specific gravity: 4.5. Tenacity: brittle. Uses: in heavy muds in oil-well drilling, to increase brilliance in the glass-making industry, as filler for paper, cosmetics, textiles, linoleum, rubber goods, paints. Barite generally occurs in a white massive variety (often appearing earthy when weathered), although some clear to bluish, bladed barite crystals have been observed in several vein deposits in central Kentucky, and commonly occurs as a solid solution series with celestite where barium and strontium can substitute for each other. Various nodular zones have been observed in Silurian–Devonian rocks in east-central Kentucky. -
A Review of Feldspar Alteration and Its Geological Significance in Sedimentary Basins from Shallow Aquifers to Deep Hydrocarbon
Originally published as: Yuan, G., Cao, Y., Schulz, H.-M., Hao, F., Gluyas, J., Liu, K., Yang, T., Wang, Y., Xi, K., Li, F. (2019): A review of feldspar alteration and its geological significance in sedimentary basins: From shallow aquifers to deep hydrocarbon reservoirs. - Earth-Science Reviews, 191, pp. 114—140. DOI: http://doi.org/10.1016/j.earscirev.2019.02.004 Earth-Science Reviews 191 (2019) 114–140 Contents lists available at ScienceDirect Earth-Science Reviews journal homepage: www.elsevier.com/locate/earscirev A review of feldspar alteration and its geological significance in sedimentary basins: From shallow aquifers to deep hydrocarbon reservoirs T ⁎ ⁎ Guanghui Yuana,b, , Yingchang Caoa,b, , Hans-Martin Schulzc, Fang Haoa, Jon Gluyasd, Keyu Liua, Tian Yanga, Yanzhong Wanga, Kelai Xia, Fulai Lia a Key laboratory of Deep Oil and Gas, School of Geosciences, China University of Petroleum, Qingdao, Shandong 266580, China b Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266071, China c GFZ German Research Centre for Geosciences, Section 4.3, Organic Geochemistry, Telegrafenberg, D-14473 Potsdam, Germany d Department of Earth Sciences, Durham University, Durham DH1 3LE, UK ARTICLE INFO ABSTRACT Keywords: The feldspar group is one of the most common types of minerals in the earth's crust. Feldspar alteration (in- Feldspar alteration cluding the whole processes of feldspar dissolution, transfer of released solutes, and secondary mineral pre- Dissolution mechanisms cipitation) is ubiquitous and important in fields including resources and environmental sciences. This paper Rate law provides a critical review of feldspar alteration and its geological significance in shallow aquifers to deep hy- Organic-inorganic interaction drocarbon reservoirs, as assessed from peer-reviewed paper in the literature. -
THE PARAGENETIC RELATIONSHIP of EPIDOTE-QUARTZ HYDROTHERMAL ALTERATION WITHIN the NORANDA VOLCANIC COMPLEX, QUEBEC R' the PARAGENETIC RELATIONSHIPS of EPIDOTE-QUARTZ
TH 1848 THE PARAGENETIC RELATIONSHIP OF EPIDOTE-QUARTZ HYDROTHERMAL ALTERATION WITHIN THE NORANDA VOLCANIC COMPLEX, QUEBEC r' THE PARAGENETIC RELATIONSHIPS OF EPIDOTE-QUARTZ HYDROTHERMAL ALTERATION WITHIN THE NORANDA VOLCANIC COMPLEX, QUEBEC Frank Santaguida (B.Sc., M.Sc.) Thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Earth Sciences Carleton University Ottawa, Ontario, Canada May, 1999 Copyright © 1999, Frank Santaguida i The undersigned hereby recommend to the Faculty of Graduate Studies and Research acceptance of the thesis, THE PARAGENETIC RELATIONSHIPS OF EPIDOTE-QUARTZ HYDROTHERMAL ALTERATION WITHIN THE NORANDA VOLCANIC COMPLEX, QUEBEC submitted by Frank Santaguida (B.Sc., M.Sc.) in partial fulfillment of the requirements for the degree of Doctor of Philosophy ,n. cGJI, Chairman, Department of Earth Sciences \ NW Thesis Supervisor /4, ad,/ External Examiner ii ABSTRACT Epidote-quartz alteration is conspicuous throughout the central Noranda Volcanic Complex, but its relationship to the Volcanic-Hosted Massive Sulphide (VHMS) deposits is relatively unknown. A continuum of alteration textures exist that reflect epidote abundance as well as alteration intensity. The strongest epidote-quartz alteration phase is represented by small discrete "patches" of complete groundmass replacement that are concentrated in discrete zones. The largest and most intense zones are spatially contained in mafic volcanic eruptive centres, the Old Waite Paleofissure and the McDougall- Despina Eruptive Centre. Therefore, epidote-quartz alteration is regionally semi- conformable and is not restricted to the hangingwall or footwall of the VHMS deposits. Epidote-quartz alteration is absent from the alteration pipes associated with sulphide mineralization. -
Mineralogy of a Layered Gabbro Deformed During Magmatic
American Mineralogist, Volume 74, pages 101-112, 1989 Mineralogy of a layered gabbro deformedduring magmatic crystallizationo western Sierra Nevada foothills" California Rorrnr K. SpmNcrn Departmentof Geology,Brandon University, Brandon, Manitoba R7A 6A9, Canada ABSTRACT In the 162 Ma Pine Hill intrusive complex of northern California, a synformal, layered pyroxenite-gabbro-dioritebody, the crystallization sequenceand compositional variation of cumulus and intercumulus minerals indicate that magmatic crystallization was char- acteized by a high initial oxygenfugacity, log,ofo,in the rangeof -4 to -9, which allowed the early precipitation of abundant titanomagnetite; the oxygen fugacity decreasedless than two log units with crystallizalion. The magmatic crystallization sequenceis ol + aug, ol + aug * mt, ol + aug + mt + pl, ol + aug + mt + pl + opx(invertedfrom pig) and aug + mt + pl + opx (inverted from pig) * qz. Pigeonite crystallization is evidenced by 001 exsolution lamellae in orthopyroxene of Enrr. Superimposedupon this sequenceare intercumulus minerals, which crystallized from magma trapped within cumulates, and biotite and calcic amphibole, which largely formed from a subsolidusreaction of a residual hydrous fluid phasewith primary minerals. Mineral compositional rangesare plagioclase, Ann, to Anrr; olivine, Fo, to Fooo;augite, CanrMgrFento CaorMg.rFerr;Ca-poor pyroxene, Ca,Mgr"Fe' to Ca,MgorFeon;Mgl(Mg * Fe * Mn) of calcic amphibole, 0.74 to 0.48; and Me/(Me * Fe * Mn) of biotite, 0.78 to 0.45. Prior to complete solidification (>900/o crystallized), deformation of the complex coincided with an abrupt decreasein Mg/(Mg * Fe) values for the mafic silicates. This compositional discontinuity is attributed to a decreasein oxygen fugacity of the crystallizing magma causedby an exchangebetween the fluid phaseof adjacentcountry rock and the fluid phaseof the magma during deformation. -
AM56 447.Pdf
THE AMERTCAN MINERAIOGIST, VOL. 56, MARCTI-APRIL, 1971 REFINEMENT OF THE CRYSTAL STRUCTURES OF EPIDOTE, ALLANITE AND HANCOCKITE W. A. Dorr,a.sr.,Department of Geology Universi.tyof California,Los Angeles90024. Assrnlcr Complete, three-dimensional crystal structure studies, including site-occupancy refine- ment, of a high-iron epidote, allanite, and hancockite have yielded cation distributions Car.ooCaroo(Alo gaFeo.os)Alr.oo(Alo zFeo.zo)SiaOrsH for epidote, Car oo(REo.zrCao:e)(AIs6t Feo ar)AL.oo(Alo.rzFeo$)SLOr3H for allanite, and Car.oo(PbosSro zrCao.zs) (Alo.eoFeo u)Alr.oo- (Al0 16Fe0.84)SLO13Hfor hancockite. These results when combined with those obtained in previous epidote-group refinements establish group-wide distribution trends in both the octahedral sites and the large-cation sites. Polyhedral expansion or contraction occurs at those sites involved in composition change but a simple mechanism, involving mainly rigid rotation of polyhedra, allows all other polyhedra to retain their same geometries in aII the structures examined. fNrnolucrtoN As part of a study of the structure and crystal chemistry of the epidote- group minerals, the first half of this paper reports the results of refine- ment of the crystal structures of three members of this group: allanite, hancockite, and (high-iron) epidote. Also, as an aid in assigning the ps2+, ps3+ occupancy of the sites in allanite, a preliminary Md,ssbauer spectral analysis of this mineral is presented. In the second half these structures are compared with three other members of the epidote group that were recently refined, clinozoisite (Dollase, 1968), piemontite (Dollase, 1969), and low-iron epidote (P. -
EPIDOTE 3+ Ca2(Fe ,Al)3(Sio4)3(OH) (See Also Clinozoisite) an Abundant and Common Mineral Either of Hydrothermal Or Metamorphic Origin
EPIDOTE 3+ Ca2(Fe ,Al)3(SiO4)3(OH) (see also clinozoisite) An abundant and common mineral either of hydrothermal or metamorphic origin. In various greenschists with chlorite and actinolite; in silicate marbles; in veins cutting granites and metamorphic rocks such as amphibolite; and in vesicles in basaltic rocks. In the native copper deposits it is abundant in both veins and basaltic lodes and locally also in the Calumet and Hecla Conglomerate. It is especially abundant in the Evergreen and succeeding lodes of that series and Figure 75: A 1.5 mm epidote crystal from the Osceola in the Isle Royale lode (Butler and Burbank, 1929). mine, Calumet, Houghton County. Dan Behnke Epidote forms a solid solution series with specimen and photograph. clinozoisite, and chemical analyses of Copper Country epidotes, though iron dominant, show a the Number 10 shaft (Falster, 1978). 9. Found in considerable compositional range between these the Jacobsville Sandstone as a heavy detrital species two species (Stoiber and Davidson, 1959; Livnat, (Denning, 1949). 10. Champion mine, 1983). “Pistacite” is an obsolete name for green Painesdale. 11. Laurium mine, Osceola. 12. epidote-clinozoisite series minerals. Northern and Tamarack mine, Calumet. Southern Peninsulas. Keweenaw County: 1. Mohawk mine. 2. Gratiot County: Near Ithaca, T10N, R2W in Seneca mines, Numbers 1 and 2: In fissure veins Michigan Basin Deep Drill Hole in both altered (Stoiber and Davidson, 1959). 3. Ojibway mine. basalt-gabbro units (McCallister et al., 1978). 4. Along shore near Epidote Lake on Isle Royale: Massive, pale green band (Dustin, 1931). 5. Houghton County: 1. Calumet and Hecla mines, Jacobsville Sandstone: An accessory detrital species Osceola lode: With copper in fractures and (Denning, 1949). -
Primary Igneous Analcime: the Colima Minettes
American Mineralogist, Volume 74, pages216-223, 1989 Primary igneous analcime: The Colima minettes Jlnrns F. Lurrn Department of Earth and Planetary Sciences,Washington University, St. Louis, Missouri 63 130, U.S.A. T. Kunrrs Kvsnn Department of Geological Sciences,University of Saskatchewan,Saskatoon, Saskatchewan S7N 0W0, Canada Ansrnrcr Major-element compositions, cell constants, and oxygen- and hydrogen-isotopecom- positions are presentedfor six analcimes from differing geologicenvironments, including proposed primary @-type) analcime microphenocrysts from a late Quaternary minette lava near Colima, Mexico. The Colima analcimehas X.,.,",: 0.684, ao: 13.712A, and one of the lowest D'sOvalues yet recorded for analcime (+9.28m).The major difficulty in identifuing primary @-type) igrreousanalcime is distinguishing it from analcime formed by ion-exchangeconversion of leucite (L-type analcime) or other precursor minerals. Pet- rographic criteria are shown to be unreliable in discriminating P and L analcimes,although the higher KrO and Rb contents and D'8Ovalues of L-type crystals may be diagnostic. P- and L-type analcimescan be distinguishedfrom classichydrothermal varieties (H-type) by the lower Fe contents of the latter. H-type analcimes,however, can have 6t8Ovalues as low as 8.9Vmand cannot be distinguished from P-type analcimes by this criterion. Analcimes formed from volcanic glass or zeolite precursorsin saline, alkaline lakes (S- type) or metamorphic sequences(M-type) can be distinguished from other varieties by their higher silica contents, smaller cell constants,and higher d'8O values of > + 17.7Vm. For all types of analcime, d'8O of the channel water does not correlate with 6180of the framework oxygen. -
Petrography Edward F
Chapter 4 Petrography Edward F. Stoddard A petrographic study was taken in order to help determine the sources of lithic artifacts found at archaeological sites on Fort Bragg. In the first phase of the study, known and suspected archaeological quarry sites in the central Piedmont of North Carolina were visited. From each quarry, hand specimens were collected and petrographic thin sections were examined in an attempt to establish a basis for distinguishing among the quarries. If material from each quarry was sufficiently distinctive, then quarry sources could potentially be matched with Fort Bragg lithic artifacts. Seventy-one samples from 12 quarry zones were examined (Table 4.1). Thirty- one of these samples are from five quarry zones in the Uwharrie Mountains region; 20 of these were collected and described previously by Daniel and Butler (1996). Forty specimens were collected from seven additional quarry zones in Chatham, Durham, Person, Orange, and Cumberland Counties. All quarries are within the Carolina Terrane, except the Cumberland County quarry, which occurs in younger sedimentary material derived primarily from Carolina Terrane outcrops. Rocks include both metavolcanic and metasedimentary types. Compositionally, most metavolcanic rocks are dacitic and include flows, tuffs, breccias, and porphyries. Metasedimentary rocks are metamudstone and fine metasandstone. The Uwharrie quarries are divided into five zones: Eastern, Western, Southern, Asheboro, and Southeastern. The divisions are based primarily on macroscopic petrography and follow the results of Daniel and Butler (1996); the Uwharries Southeastern zone was added in this study. Each of the Uwharrie quarry zones represents three to six individual quarries in relatively close proximity. Rock specimens are all various felsic metavolcanic rocks, but zones may be distinguished based upon mineralogy and texture. -
Mineralogical Characteristics of Hydrothermally-Altered Andesite in Kalirejo Village and the Surrounding Areas, Indonesia
Journal of Applied Geology, vol. 3(2), 2018, pp. 99–108 DOI: http://dx.doi.org/10.22146/jag.48598 Mineralogical Characteristics of Hydrothermally-altered Andesite in Kalirejo Village and The Surrounding Areas, Indonesia Diyan Aditya Putra Pratama, I Gde Budi Indrawan,* and I Wayan Warmada Department of Geological Engineering, Faculty of Engineering, Gadjah Mada University, Yogyakarta, Indonesia ABSTRACT. Type and intensity of hydrothermal alterations affect rock engineering prop- erties and slope stability. Identification of mineralogical characteristics of rocks is essen- tial in determination of rock slope failure mechanism in a hydrothermal alteration zone. This research was conducted to identify mineralogical characteristics of hydrothermally- altered andesite in Kalirejo Village and surrounding areas, Indonesia. The research was conducted by field observation and laboratory analyses involving petrographic and X-ray Powder Diffraction (XRD) analyses. The results showed that the research area was domi- nated by argillic alteration type and high alteration intensity implying high susceptibility to slope failures. Keywords: Hydrotermal alteration · Mineralogical characteristics · Andesite · Kalirejo Vil- lage · Indonesia. 1I NTRODUCTION more detailed zonation of areas susceptible to The research area was located in Kalirejo Vil- slope failures. lage and the surroundings. It was adminis- Stability of rock slopes in tectonically active tratively located in Kulon Progo Regency (Yo- and tropical regions is controlled by several fac- gyakarta Special Province) and Purworejo Re- tors, such as slope geometry, material proper- gency (Central Java Province), Indonesia. The ties, groundwater, surface cover, and active fac- regional geological map produced by Rahardjo tors involving earthquake and rainfall. Previ- et al. (1995) indicated that the research area ous publications (e.g., Bell, 2007; Pola et al., was composed of intrusive igneous rock group 2012) have shown that hydrothermal alteration of andesite. -
Identification Tables for Common Minerals in Thin Section
Identification Tables for Common Minerals in Thin Section These tables provide a concise summary of the properties of a range of common minerals. Within the tables, minerals are arranged by colour so as to help with identification. If a mineral commonly has a range of colours, it will appear once for each colour. To identify an unknown mineral, start by answering the following questions: (1) What colour is the mineral? (2) What is the relief of the mineral? (3) Do you think you are looking at an igneous, metamorphic or sedimentary rock? Go to the chart, and scan the properties. Within each colour group, minerals are arranged in order of increasing refractive index (which more or less corresponds to relief). This should at once limit you to only a few minerals. By looking at the chart, see which properties might help you distinguish between the possibilities. Then, look at the mineral again, and check these further details. Notes: (i) Name: names listed here may be strict mineral names (e.g., andalusite), or group names (e.g., chlorite), or distinctive variety names (e.g., titanian augite). These tables contain a personal selection of some of the more common minerals. Remember that there are nearly 4000 minerals, although 95% of these are rare or very rare. The minerals in here probably make up 95% of medium and coarse-grained rocks in the crust. (ii) IMS: this gives a simple assessment of whether the mineral is common in igneous (I), metamorphic (M) or sedimentary (S) rocks. These are not infallible guides - in particular many igneous and metamorphic minerals can occur occasionally in sediments. -
Epidote Group
Epidote Group Chemically complex (A 2M3Si 3O12 OH) A sites contain large, high-coordination cations Ca, Sr, lanthanides M sites are octohedrally-coordinated, trvalent (occasionally divalent) cations Al, Fe 3+ , Mn3+, Fe2+, Mg2+ Space group: P21/m Crystal class: monoclinic 2/m a=8.98 b=5.64 c=10.22 (angstroms) a=1.670-1.715 b=1.674-1.725 g=1.690-1.734 Z=2 Solid solution extends form clinozoisite to epidote Chemical formula Epidote Ca2(Al,Fe)Al2O(SiO4)(Si2O7)(OH) Clinozoisite Ca2Al3O(SiO4)(Si2O7)(OH) Zoisite is an orthorhombic polymorph (Pnmc) of clinozoisite 1 Epidote structure type Two types of edge-sharing octahedra - single chain of M(2) - zig-zag chain of central M(1) and peripheral M(3) These chains are crosslinked by SiO4 and SiO7 groups Between the chains and crosslinks are relatively large cavities which house the A(1) and A(2) cations. Silica tetrahedra - Si (1) and Si(2) share O(9), forming an Si 2O 7 group - Si (3) forms an isolated SiO 4 group Each tetrahedron retains essentially its same shape and size in all structures In a given bonding situation a particular Si-O bond type has nearly the same value in each mineral, however, the different Si-O bond types vary in length due to local charge imbalance. MO 6 Octahedra - Unequal occupancy of the 3 different octahedral positions, M(1), M(2), M(3). M(2) octahedral chain contains only Al atoms M(1) and M(3) substitute entirely with non-Al atoms - the M(3) octahedra contain a larger fraction 2 A(1) and A(2) Polyhedra Clinozoisite and epidote have A sties occupied entirely by calcium atoms. -
Epidote in Calc-Alkaline Magmas: an Experimental Study of Stability, Phase Relationships, and the Role of Epidote in Magmatic Evolution
American Mineralogist, Volume 81, pages 462-474, 1996 Epidote in calc-alkaline magmas: An experimental study of stability, phase relationships, and the role of epidote in magmatic evolution MAX W. SCHMIDT1,2 ANDALAN B. THOMPSON3 'Departement Geologie, Universite Blaise Pascal, CNRS-URAIO, 5 rue Kessler, 63038 Clermont-Ferrand, France 2Bayerisches Geoinstitut, Universitat Bayreuth, D-95440 Bayreuth, Germany 3lnstitut flir Mineralogie and Petrographie, Sonneggstrasse 5, Eidgenossische Technische Hochschule, CH-8092 Zurich, Switzerland ABSTRACT Experiments on tonalite and granodiorite were performed at conditions ranging from 2.1 to 18 kbar and 550 to 850°C to establish the magmatic stability field of epidote as a function of P, T, and f02. At water-saturated conditions and f02 buffered by NNO, epidote has a wide magmatic stability field in tonalite. At 13 kbar, this field extends from the wet solidus at 630 to 790 0c. The low-pressure intersection of the magmatic epidote crystallization reaction and the H20-saturated tonalite solidus, and hence the minimum pressure for magmatic epidote, occurs at about 5 kbar. The Clapeyron slopes of epidote melting reactions are moderately positive in P-T space at pressures below the intersection of the epidote melting and the gamet-in reactions at 13 kbar, 790°C. At this intersection, epidote reaches its maximal thermal stability (790°C) in tonalite-H20. In the presence of garnet, that is above 14 kbar, epidote melting reactions have steep negative Clapeyron slopes in P-T space. At P-T conditions near the low-pressure intersection of the epidote melting reaction with the water-saturated solidus, experiments were also performed with f02 buffered by HM.