Geology 222 Laboratory Project Layered Mafic Intrusions
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Beneficiation of Stillwater Complex Rock for the Production of Lunar Simulants
National Aeronautics and NASA/TM—2014–217502 Space Administration IS20 George C. Marshall Space Flight Center Huntsville, Alabama 35812 Beneficiation of Stillwater Complex Rock for the Production of Lunar Simulants D.L. Rickman Marshall Space Flight Center, Huntsville, Alabama C. Young Metallurgical and Materials Engineering, Montana Tech, Butte, Montana D. Stoeser USGS, Denver, Colorado J. Edmunson Jacobs ESSSA Group, Huntsville, Alabama March 2014 The NASA STI Program…in Profile Since its founding, NASA has been dedicated to the • CONFERENCE PUBLICATION. Collected advancement of aeronautics and space science. The papers from scientific and technical conferences, NASA Scientific and Technical Information (STI) symposia, seminars, or other meetings sponsored Program Office plays a key part in helping NASA or cosponsored by NASA. maintain this important role. • SPECIAL PUBLICATION. Scientific, technical, The NASA STI Program Office is operated by or historical information from NASA programs, Langley Research Center, the lead center for projects, and mission, often concerned with NASA’s scientific and technical information. The subjects having substantial public interest. NASA STI Program Office provides access to the NASA STI Database, the largest collection of • TECHNICAL TRANSLATION. aeronautical and space science STI in the world. English-language translations of foreign The Program Office is also NASA’s institutional scientific and technical material pertinent to mechanism for disseminating the results of its NASA’s mission. research and development activities. These results are published by NASA in the NASA STI Report Specialized services that complement the STI Series, which includes the following report types: Program Office’s diverse offerings include creating custom thesauri, building customized databases, • TECHNICAL PUBLICATION. -
Noritic Anorthosite Bodies in the Sierra Nevada Batholith
MINERALOGICAL SOCIETY OF AMERICA, SPECIAL PAPER 1, 1963 INTERNATIONALMINERALOGICAL ASSOCIATION,PAPERS, THIRD GENERAL MEETING NORITIC ANORTHOSITE BODIES IN THE SIERRA NEVADA BATHOLITH ALDEN A. LOOMISl Department of Geology, Stanford University, Stanford, California ABSTRACT A group of small noritic plutons were intruded prior to the immediately surrounding granitic rocks in a part of the composite Sierra Nevada batholith near Lake Tahoe. Iron was more strongly concentrated in the late fluids of individual bodies than during the intrusive sequence as a whole. Pyroxenes are more ferrous in rocks late in the sequence, although most of the iron is in late magnetite which replaces pyroxenes. Both Willow Lake type and normal cumulative layering are present. Cumulative layering is rare; Willi ow Lake layering is common and was formed early in individual bodies. Willow Lake layers require a compositional uniqueness providing high ionic mobility to explain observed relations. The Sierran norites differ from those in large stratiform plutons in that (1) the average bulk composition is neritic anorthosite in which typical rocks contain over 20% AbO" and (2) differentiation of both orthopyroxene and plagioclase produced a smooth progressive sequence of mineral compositions. A plot of modal An vs. En for all the rocks in the sequence from early Willow Lake-type layers to late no rite dikes defines a smooth non-linear trend from Anss-En76 to An,,-En54. TLe ratio An/ Ab decreased faster than En/Of until the assemblage Anso-En65 was reached and En/Of began to decrease more rapidly. Similar plots for large stratiform bodies show too much scatter to define single curves. -
Geochemistry of the Mafic and Felsic Norite: Implications for the Crystallization History of the Sudbury Igneous Complex, Sudbury Ontario
Geochemistry of the Mafic and Felsic Norite: Implications for the Crystallization History of the Sudbury Igneous Complex, Sudbury Ontario G. R. Dessureau Mineral Exploration Research Centre, Department of Earth Sciences, Laurentian University, Sudbury, ON, P3E 6B5 e-mail: [email protected] Introduction Whistle Embayment Geology The 1.85 Ga Sudbury Igneous Complex The Whistle Embayment occurs along the (SIC) is a 60 x 30 km layered igneous body NE margin of the basin under the Main Mass of the occupying the floor of a crater in northern Ontario. SIC and extends into the footwall as an Offset dyke The SIC comprises, from base to top: a (Whistle/Parkin Offset). Pattison (1979) and discontinuous unit of sulfide-rich, inclusion-bearing Lightfoot et al. (1997) provide detailed descriptions norite (Contact Sublayer), mafic norite, felsic of the embayment environment at Whistle. The norite, gabbro transition zones, and granophyre embayment contains up to ~300m of inclusion-rich, (Main Mass). Concentric and radial Quartz Diorite sulfide-bearing Sublayer in a well-zoned funnel Offset Dykes extend into the footwall rocks. extending away from the base of the SIC. Poikilitic, The distributions of the Sublayer and hypersthene-rich Mafic Norite occurs in and along associated Ni-Cu-PGE ores are controlled by the the flanks of the embayment as discontinuous morphology of the footwall: the Sublayer and lenses between the Sublayer and the Felsic Norite. contact ores are thickest within km-sized radial The Felsic Norite in the Whistle area ranges from depressions in the footwall referred to as ~450m thick adjacent to the embayment to >600m embayments (e.g., Whistle Embayment) and thick directly over the embayment. -
The Original Lithologies and Their Metamorphism
BASIC PLUTONIC INTRUSIONS OF THE RISÖR SÖNDELED AREA, SOUTH NORWAY: THE ORIGINAL LITHOLOGIES AND THEIR METAMORPHISM IAN C. STARMER Department of Geology, University of Nottingham, England Present address: Dept. of Geo/ogy, Queen Mary College, London, E. l STARMER, I. C.: Basic plutonic intrusions of the Risör-Sändeled area South Norway: The original Jithologies and their metamorphism Norsk Geologisk Tidsskri/1, Vol. 49, pp. 403-431. Oslo 1969. The emplacement of Pre-Cambrian basic intrusions is shown to have been a polyphase process and to have occurred Jargely between two major periods of metamorphism. The original igneous lithologies are discussed and a regional differentiation series is demonstrated, with changes in rock-type accompanied by some cryptic variation in the component minerals. Metamorphism after consolidation converted the intrusives to coronites and eaused partial amphibolitisation. Corona growths are described and attributed to essentially isochemical recrystal lisations in the solid-state, promoted by the diffusion of ions in inter granular fluids. The amphibolitisation of the bodies is briefly outlined, and it is concluded that the formation of amphibolite involved the intro duction of considerable amounts of extraneous water. The criterion for demoostrating the onset of amphibolitisation is thought to be the intemal replacement of pyroxene by homblende, contrasting with the replacement of plagioclase by various amphiboles during corona growth. Both amphibolites and coronites have been scapolitised, and this may have been an extended process which certainly continued after amphi bolitisation. Regional implications are considered and it is suggested that a !arge mass of differentiating magma may have underlain the whole region in Pre-Cambrian times. -
Petrology of the Noritic and Gabbronoritic Rocks Below the J-M Reef in the Mountain View Area, Stillwater Complex, Montana
Petrology of the Noritic and Gabbronoritic Rocks below the J-M Reef in the Mountain View Area, Stillwater Complex, Montana U.S. GEOLOGICAL SURVEY BULLETIN 1674-C Chapter C Petrology of the Noritic and Gabbronoritic Rocks below the J-M Reef in the Mountain View Area, Stillwater Complex, Montana By NORMAN J PAGE and BARRY C. MORING U.S. GEOLOGICAL SURVEY BULLETIN 1674 CONTRIBUTIONS ON ORE DEPOSITS IN THE EARLY MAGMATIC ENVIRONMENT DEPARTMENT OF THE INTERIOR MANUEL LUJAN, JR., Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1990 For sale by the Books and Open-File Reports Section, U.S. Geological Survey Federal Center, Box 25425 Denver, CO 80225 Library of Congress Cataloging-in-Publication Data Page, Norman, J Petrology of the noritic and gabbronoritic rocks below the J-M Reef in the Mountain View area, Stillwater Complex, Montana / by Norman J Page and Barry C. Moring. p. cm. (U.S. Geological Survey bulletin ; 1674-C) (Contributions on ore deposits in the early magmatic environment Includes bibliographical references. Supt. of Docs, no.: I 19.3: 1674-C 1. Petrology Beartooth Mountains Region (Mont, and Wyo.) 2. Geolo gy Beartooth Mountains Region (Mont, and Wyo.) I. Moring, Barry C. II. Title. III. Title: Stillwater Complex, Montana. IV. Series. V. Series: Contri butions on ore deposits in the early magmatic environment ; ch. -
The Bushveld Igneous Complex
The Bushveld Igneous Complex THE GEOLOGY OF SOUTH AFRICA’S PLATINUM RESOURCES By C. A. Cousins, MSC. Johannesburg Consolidated Investment Company Limited A vast composite body of plutonic and volcanic rock in the central part of the Transvaal, the Bushveld igneous complex includes the platinum reef worked by Rustenburg Platinum Mines Limited and constituting the world’s greatest reserve of the platinum metals. This article describes the geological and economic aspects of this unusually interesting formation. In South Africa platinum occurs chiefly in square miles. Two of these areas lie at the the Merensky Reef, which itself forms part of eastern and western ends of the Bushveld and the Bushveld igneous complex, an irregular form wide curved belts, trending parallel to oval area of some 15,000 square miles occupy- the sedimentary rocks which they overlie, and ing a roughly central position in the province dipping inwards towards the centre of the of the Transvaal. A geological map of the Bushveld at similar angles. The western belt area, which provides the largest known has a flat sheet-like extension reaching the example of this interesting type of formation, western boundary of the Transvaal. The is shown on the facing page. third area extends northwards and cuts out- The complex rests upon a floor of sedi- side the sedimentary basin. Its exact relation- mentary rocks of the Transvaal System. This ship to the other outcrops within the basin floor is structurally in the form of an immense has not as yet been solved. oval basin, three hundred miles long and a As the eastern and western belts contain hundred miles broad. -
Attributes of Skaergaard-Type PGE Reefs
Attributes of Skaergaard-Type PGE Reefs James D. Miller, Jr.1 and Jens C. Ø. Andersen2 1Minnesota Geological Survey, c/o NRRI, University of Minnesota-Duluth, 5013 Miller Trunk Hwy., Duluth, MN, 55811 , USA 2Camborne School of Mines, University of Exeter, Redruth, Cornwall, TR15 3SE UK e-mail: [email protected], [email protected] Stratiform, platinum group element (PGE) peridotite, pyroxenite, and dunite are usually deposits have long been known to occur in quantitatively minor. When well-differentiated, ultramafic-mafic intrusive complexes such as such intrusions display a simplified cumulus Bushveld and Stillwater (Naldrett, 1989b). stratigraphy following the scheme: Ol or Pl only-> Commonly known as PGE reefs, such deposits are Ol + Pl -> Pl + Cpx + FeOx ± Ol -> Pl + Cpx + typically found near the transition from ultramafic FeOx + Ol + Ap. They have a strong cryptic to mafic cumulates where they occur as 1-3 meter layering towards iron-enrichment indicative of thick intervals enriched in PGEs (1-20 ppm) and Fenner-type differentiation. They differ from trace to moderate amounts of sulfide (0.5-5 wt %). classic PGE reef-bearing intrusions by lacking a However, relatively recent discoveries have significant ultramafic component (early olivine- demonstrated that potentially economic stratiform only crystallization is minor to absent in most PGE mineralization may also occur in tholeiitic tholeiitic intrusions) and by being poor in mafic layered intrusions. Au- and PGE-bearing orthopyroxene (inverted pigeonite is rarely a layers -
Monchegorsk Layered Intrusion, Fennoscandian Shield)
minerals Article Chromite Mineralization in the Sopcheozero Deposit (Monchegorsk Layered Intrusion, Fennoscandian Shield) Artem V. Mokrushin 1,* and Valery F. Smol’kin 2 1 Geological Institute—Subdivision of the Federal Research Centre “Kola Science Centre of the Russian Academy of Sciences”, 14 Fersman Street, 184209 Apatity, Russia 2 Vernadsky State Geological Museum of the Russian Academy of Sciences, 11/11 Mokhovaya Street, 125009 Moscow, Russia; [email protected] * Correspondence: [email protected]; Tel.: +7-(902)133-39-95 Abstract: In 1990, the Sopcheozero Cr deposit was discovered in the Monchegorsk Paleoprotero- zoic layered mafic-ultramafic layered intrusion (Monchepluton). This stratiform early-magmatic deposit occurs in the middle part of the Dunite Block, which is a member of the Monchepluton layered series. The Cr2O3 average-weighted content in ordinary and rich ores of the deposit is 16.65 and 38.76 wt.%, respectively, at gradually changing concentrations within the rich, ordinary and poor ore types and ore body in general. The ores of the Sopcheozero deposit, having a ratio of Cr2O3/FeOtotal = 0.9–1.7, can serve as raw materials for the refractory and chemical industries. The ore Cr-spinel (magnochromite and magnoalumochromite) is associated with highly magnesian olivine (96–98 Fo) rich in Ni (0.4–1.1 wt.%). It confirms a low S content in the melt and complies with the low oxygen fugacity. The coexisting Cr-spinel-olivine pairs crystallized at temperatures ◦ from 1258 to 1163 C, with accessory Cr-spinel crystallizing at relatively low, while ore Cr-spinel at higher temperatures. The host rock and ore distinguish with widespread plastic deformations of ◦ Citation: Mokrushin, A.V.; Smol’kin, olivine at the postcrystallization phase under conditions of high temperature (above 400 C) and V.F. -
Geomorphology of the Bushveld Complex
Cademo Lab. Xeo16xico de Laxe Coruña. 1997. Vol. 22, pp. 209-227 Geomorphology of the Bushveld Complex Geomorfología del Complejo de Bushveld LAGEAT,Y. This paper deals wich che differenc relacion becween scruccure and lichology in che geomorphology of che Bushveld Complexo The final resules demonscrace chac, even so differenc scale ofsize, widerfor che epirogenic-cecconic movements and smaller for che lichology, che cwo faccors need co be considered for a beccer underscanding ofche landscape evolucion ofche area. Key words: ulerabasic and basic rocks, Bushveld Complex, scruccural geomorphology, lichological differences. LAGEAT, Y. (Universicé Blaise Pascaland UPRES-A 6042 (CNRS). Clermont-Ferrand (France) 210 Lageat, Y. CAD. LAB. XEOL. LAXE 22 (997) INTRODUCTION subdued topography. So, being concerned with the relationships between scenery and In spiteofthestrong emphasisonclimatic structure, the study wil1 consider two topics in French geomorphology since the different but complementary topics: fifties, research dealing with structural differential erosion and regional evolution landforms developed in crystalline shields ofa shield area (Y. LAGEAT, 1989). pioneered by the late Professor P. Birot has been upheld. In numerous regional monographs, widely distributed between GEOLOGICAL POTENTIAL theArcticCircleand theTropicofCapricorn, special attention has been devoted to the A presentation of the geology of the relationships between landforms and Bushveld Complex is essential to any geological structure, with the purpose to understanding of its surface morphology. distinguish between the direct control of Ranging in composition from ultrabasic ro recent faulting and the response of acid, it outcrops largely within a region contrasting rock units todifferential erosiono covered bya characteristicvegetation termed This ambiguity may be easily overcome in «Bushveld». -
62237 Troctolitic Anorthosite 62.4 Grams
62237 Troctolitic Anorthosite 62.4 grams Figure 1: Photo of 62237. NASA S72-41797 (B&W), NASA S72-38959 (color). Cube is 1 cm. Introduction 62237 and 62236 are chalky white rocks that were Warren and Wasson (1977) concluded that 62237 is collected together along with 62235 and incidental soil, “chemically pristine”, because it was lacking in from the rim of Buster Crater, station 2, Apollo 16 meteoritic siderophiles. (figure 2), where they were found half buried in the regolith (Sutton 1981). The mineral chemistry of these 62237 has been crushed to form a cataclastic texture, rocks is similar and indicates that they belong to the but, in places, the original coarse-grained igneous suite of lunar plutonic rocks termed ferroan anorthosite texture can be discerned by relic clasts (figure 3). (James 1980). Mineralogy Olivine: Olivine (Fo ) crystals up to 3 mm in size Petrography 59-61 Dymek et al. (1975) concluded that 62237 was a slowly are reported in 62237 by Dymek et al. (1975). Warren cooled plutonic lunar rock (figure 1). The mineralogy and Wasson (1977) and Bersch et al. (1991) also of 62237 is that of a ferroan anorthosite with fairly provided analyses of olivine in 62237. Dymek et al. abundant (~20%) mafic minerals (figure 5). noted that olivine in 62237 was extremely depleted in Ca. Lunar Sample Compendium C Meyer 2011 Figure 2: Location of 62237. Pyroxene: Dymek et al. (1975) and Bersch et al. (1991) determined the composition of pyroxene in 62237 (figure 4). Plagioclase: Plagioclase in 62237 is An95-99 and contains only small amount of minor elements (Dymek et al. -
Tonalite, Diorite, Gabbro, Norite, and Anorthosite
GLY 4310 LAB 6 TONALITE, DIORITE, GABBRO, NORITE, AND ANORTHOSITE LEUCOCRATIC (0-30% MAFIC) PHANERITIC ROCK FELSICS MAFICS NOTES Plagioclase Quartz K-Spar Biotite Hornblende Ortho- Clino- Pyroxene Pyroxene 32 90% 10% Medium-grained Anorthosite Subh Anh Clino-pyroxene is augite. 2.5mm green/black Plagioclase is anorthite. 10mm laths or 2mm 7mm TRACE MINERAL: equant fibrous euhedral pyrite. Rock has pale bluish hue. 340 90% 3% 7% Medium-grained Anorthosite Anh-subh Anh-subh Anh-subh Clinopyroxene is white to tan Black Dark green probably augite. 3mm laths 1.5mm 1.5mm Plagioclase is anorthite. TRACE MINERALS: Biotite & muscovite. 1 GLY 4310 LAB 6 MESOTYPE (30-60% MAFIC) PHANERITIC ROCK FELSICS MAFICS NOTES Plagioclase Quartz K-Spar Biotite Hornblende Ortho- Clino- Pyroxene Pyroxene 24 45% 25% 8% 17% 5% Medium-Coarse grained. Tonalite Anh Anh Anh Subh Anh Clinopyroxene is augite. White/gray Gray 2mm 5mm 4mm 8mm Greenish Plagioclase is probably 3mm 2mm Columnar 1.5mm andesine. Laths or Rounded Some of the plagioclase equant crystals show twinning in hand specimen. 28 32% 3% 55% 5% Medium-grained. Hornblende Subh Anh Subh Anh Clinopyroxene is augite. Gabbro Clear gray Grayish Black Greenish Plagioclase displays some 1.5mm laths 2mm 1.5mm 5mm 0.5mm twinning. Rounded Equant 2 GLY 4310 LAB 6 MELANOCRATIC (60-100% MAFIC) PHANERITIC ROCK FELSICS MAFICS NOTES Plagioclase Quartz K-Spar Biotite Hornblende Ortho- Clino- Pyroxene Pyroxene 25 17% 7% 12% 60% Medium-coarse grained. Diorite Anh Anh Anh Subh Rock is equigranular. White Gray 2mm Black SPHENE - 4%, Subh, 1mm, 0.5mm, 2mm, 1mm, yellow, elongated. -
Monographs of the USGS Vol. XXXVI – Part I – Page 127 of 133 PLATE XXXVI
PLATE XXXIV. PLATE XXXV. FIG. A. FIG. A. (Sp. No. 23746. Without analyzer, x 17.) (Sp. No. 26059. Without analyzer, x 18.) Contact product of a granite. This muscovite-biotite-gneiss (?) Photomicrograph showing an eruptive contact between granite is the result of contact action of a granite upon a graywacke. and metamorphosed sedimentary rock. As a result of this Complete recrystallization of the sedimentary rock has taken contact the elements of the granite have become partly place, with the production of a porphyritic schistose structure. automorphic. The center of the figure is occupied by a quartz The large porphyritic muscovite plates seen as white areas in phenocryst which is partly surrounded by the schistose the photomicrograph evidently represent the last products of metamorphic product. It contains, near the edge, grains of recrystallization, as they include all of the minerals which have feldspar and flakes of mica, and thus an imperfect poikilitic been previously formed. They are possibly to be looked upon zone is produced. The mineral constituents of the as the product of mineralizers, to whose action may also be metamorphosed sedimentary are arranged parallel to the referred the presence of tourmaline, which occurs in the contours of the phenocrysts. (Described, p. 198.) section. The irregular white areas represent quartz and FIG. B. feldspar. Dark greenish-brown biotite is included in the muscovite, and with iron oxides occupies the areas which in (Sp. No. 26059. With analyzer, x 18.) the figure are dark. (Described, p. 197.) The same section as the above, viewed between crossed FIG. B. nicols. (Described, p.