Komatiite Hosted Tree

Total Page:16

File Type:pdf, Size:1020Kb

Komatiite Hosted Tree LAYERED INTRUSION-HOSTED VANADIUM Trap - Chemical/ Source Active Pathway Trap - Chemical Scrubber Preservation physical scrubber Transporting large volumes of Long-lived fractionation to produce Fe-oxide Formation of oxidised seams within Exhumation and preservation of vanadium Voluminous mantle melting mantle-derived magma through the saturation a layered mafic-ultramafic intrusion orebodies crust Critical Critical Process : ? Processes within the magma Mantle plumes to transport large Intracontinental rift zones where Pooling of mantle Stable Preservation High-degree mantle melting to produce Delayed onset of Fe- chamber? Density settling, magma Weathering of volumes of mantle-derived magma extensional forces produced passive derived magma in plateaus of the upper voluminous mafic-ultramafic magmas oxide saturation mixing, pressure changes, liquid magnetite layers through the crust melting of the mantle the crust with slow parts of immiscibility rates of layered erosion intrusions Constituent ProcessConstituent What are the processes that that processes are the What critical process the control Archean granite Archean granite Domal uplift Sedimentary basins Volcanic rifted Plateaus Large Igneous Large Igneous Triple junctions Kimberlites and Rocks coeval with Layered mafic- Magnetitite-ilmenite chromatite greenstone greenstone formed by caused by margins that may and areas Tilted Vanadomaghemite Provinces (LIPs) - Provinces (LIPs) - where mantle carbonatites that or indicators of ultramafic Dykes and sills Tholeiitic magmas layers within a layered mafic- terranes with terranes with underplating of subsidence after occur as a result of with domains and hematite Flood basalts, Flood basalts, plumes that reach can mark where rifting. intrusions ultramafic intrusion associated felsic komatiite-tholeiite associated felsic komatiite-tholeiite mantle plumes the surface produce doming mantle plumes mantle plumes are abundant rocks, dyke swarms, associations – rocks, dyke swarms, associations – rifting underplating relict : sills, layered mafic- interpreted to be sills, layered mafic- interpreted to be regolith ultramafic intrsions the Archean ultramafic intrsions the Archean equivalent of LIPs equivalent of LIPs ? Targeting How can we target each constituent constituent each target we can How process Proterozoic and Proterozoic and Magnetite-ilmenite Stable Archean rock age Archean rock age Sedimentary Structure Structure Kimberlite Kimberlite Layered mafic- Dyke and sill map Tholeiitic basalt Dip map Regolith map Phanerozoic rock Phanerozoic rock Sedimentary basins Rhyolite map (m) layer map plateau map map thickness map complexity map complexity map occurrence map Structure occurrence map ultramafic intrusion (m+dhd+g+WAROX+ map (WAROX+m+g) (m) age map age map map (m) (m+dhd+g+c+s+WA layer (m) (m+chron+ENS) (m+chron+ENS) (m+dhd+g) (m+g) (m+g) (m+c) complexity map (m) (m+c) map WAMEX) (m+c+WACHEM) (m+chron+ENS) (m+chron+ENS) (m+dhd+g+c+s+WA ROX+WAMEX ROX+WAMEX) Volcanic time slice Volcanic time slice Dacite map (m) Komatiite map Komatiite Carbonatite Hornblende gabbro Detrital ilmenite map Conglomerate map Palaeocratonic Palaeocratonic Alkaline rock age occurrence map (m+dhd+g+c+s+WA occurrence map occurrence map Magnetic structure map chemistry map (m+dhd+g+c+s+WA (m+dhd+WAROX) boundary map (i) boundary map (i) map (m+chron) ROX+WAMEX+chro (m+ENS) ROX+WAMEX+chro (m+ENS) (m+c) complexity map (g) (m+c+WACHEM) (Dia) n) n) Felsic volcanic rock age map (m+chron) Coeval (sulphidic) Magnetitite- Tholeiitic basalt Dyke and sill map Tholeiitic basalt VMS age and sediments Dyke and sill map (m+dhd+g+WAROX+ Ferrodiorite map chromatite layer occurrence map occurrence map occurrence map Gravity structure occurrence map (m+dhd+g+WAROX+ WAMEX) map (m+c+WAROX) (m+c+WAROX) (m+chron) Alkaline rock (m+chron) (m+c+WACHEM) WAMEX) complexity map (g) (m+dhd+g+C+WARO occurrence map X+WAMEX) ? Layered mafic- (m+c) BIF age and Layered mafic- ultramafic intrusion Alkaline rock age occurrence map Vanadium ultramafic intrusion map map (m+chron) Palaeocratonic (m+chron) Fe-rich rhyolite map concentration in map (m+dhd+g+c+s+WA Carbonatite boundary map (i) (m+c+WACHEM) layered mafic- (m+dhd+g+c+s+WA ROX+WAMEX) occurrence map ultramafic intrusion ROX+WAMEX) (m+c) VMS age and (c) BIF age and occurrence map occurrence map Felsic volcanic rock (m+chron) : (m+chron) occurrence map (m) Syenite occurrence map (m+c) Data Sources m = mapping c = geochemistry g = geophysical interpretation chron = geochronology Quartz andesite Pyroxenite i = isotopic ratios (e.g. Nd-Sm) dhd = drillhole database map (m) occurrence map s = reflectance spectroscopy hydro = hydrochemistry data (m+c) WAMEX= WAMEX database/reports reg = regolith map WAROX = WAROX database soil = soil map Dia = Diamond exploration data Mappable Proxies Mappable Which layers are needed and how are they created they how are and needed are layers Which Blue text = geological proxy layer available in the Atlas [hyperlinked] Recommended reference = Geological Survey of Western Australia 2019, Mineral Systems Atlas: Vanadiferous Titanomagnetite system, Department of Mines, Industry Regulations and Safety, accessed date, <www.dmp.wa.gov.au/msa>.
Recommended publications
  • 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
    [Show full text]
  • 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.
    [Show full text]
  • Geology 222 Laboratory Project Layered Mafic Intrusions
    Geology 222 Laboratory Project Layered Mafic Intrusions Layered mafic intrusions present an unusual record of a natural crystallization experiment. In an ideal case, a magma chamber is filled with a mafic liquid of relatively low viscosity. Crystals of sufficient density that grow from this liquid settle to the bottom of the magma chamber as they grow. Layers of crystals are formed yielding a “magmatic sedimentary rock”. The first-formed crystals are on the bottom of the magma chamber and later-formed crystals are stratigraphically above earlier-formed crystals. If one looks at the compositions of the crystals in the layers, changes that occur during the solidification of the magma can be discovered. Actual layered mafic intrusions are rarely as simple as the idealized model. Plagioclase commonly sinks, rather than floats as its density suggests it would do. Crystal settling can be rhythmic rather than continuous. Density currents can develop and lead to cross-bedding. Some (intercumulus) liquid can be trapped as a pore fluid among the settled crystals and may possibly be squeezed out as the crystal layers are compressed. Additional batches of magma can be added to the magma chamber over time, changing the composition of the evolving liquid. The lab assignment is to look carefully at rocks from one layered mafic intrusions for which we have thin sections (Bushveld, Kiglapait, and Stillwater). You should describe fully three thin sections from the intrusion of your choice. Chose thin sections that are not similar to one another. Identify the minerals. Give a mode. Include in your report photomicrographs or sketches of textures that you see.
    [Show full text]
  • Resources in the Upper Zone of the Bushveld Complex, South Africa
    Papers and Proceedings of the Royal Society of Tasmania, Volume 150(1), 2016 15 Fe-Ti-V-(P) RESOURCES IN THE UPPER ZONE OF THE BUSHVELD COMPLEX, SOUTH AFRICA by L.A. Fischer and Q. Yuan (with four text-figures and two plates) Fischer, L.A. & Yuan, Q. 2016 (31:viii): Fe-Ti-V-(P) resources in the Upper Zone of the Bushveld Complex, South Africa. Papers and Proceedings of the Royal Society of Tasmania 150(1): 15–22. https://doi.org/10.26749/rstpp.150.1.15 ISSN 0080-4703. Institut für Mineralogie, Leibniz Universität Hannover, 30167 Hannover, Germany, and School of Physical Sciences, University of Tasmania, Hobart, Tasmania 7001, Australia (LAF*); Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China, and Department of Geology, University of Liege, 4000 Sart Tilman, Belgium (QY). *Author for correspondence. Email: [email protected] The Bushveld Complex in South Africa is the largest layered intrusion on Earth. Its upper part is known for huge resources of iron, tita- nium, vanadium and phosphorus. Associated with the layered character of the rocks, these resources are enriched at certain levels of the intrusion, which makes it important to understand the formation processes of those layers. In this paper we give an introduction and overview of recent debates and challenges. Key Words: layered intrusion, Bushveld, resources. INTRODUCTION Fe, Ti, V and P never or only rarely occur as native elements in nature. Minerals, rich in one or more of these Iron (Fe), titanium (Ti) and vanadium (V) are important elements are mined and their components are extracted.
    [Show full text]
  • Platinum-Group Minerals in Chromitites of the Niquelândia
    Minerals 2012, 2, 365-384; doi:10.3390/min2040365 OPEN ACCESS minerals ISSN 2075-163X www.mdpi.com/journal/minerals Article Platinum-Group Minerals in Chromitites of the Niquelândia Layered Intrusion (Central Goias, Brazil): Their Magmatic Origin and Low-Temperature Reworking during Serpentinization and Lateritic Weathering Giorgio Garuti 1,*, Federica Zaccarini 1, Joaquin A. Proenza 2, Oskar A. R. Thalhammer 1 and Nelson Angeli 3 1 Department of Applied Geosciences and Geophysics, Montan Universität Leoben, Leoben 8700, Austria; E-Mails: [email protected] (F.Z.); [email protected] (O.A.R.T.) 2 Departament of Crystallography, Mineralogy and Ore Deposits, Faculty of Geology, Universitat de Barcelona, Barcelona 08028, Spain; E-Mail: [email protected] 3 Departament of Petrology and Metallogeny, Universidade Estadual Paulista, Rio Claro 13500, SP, Brazil; E-Mail: [email protected] * Author to whom correspondence should be addressed; E-Mail: [email protected]; Tel.: +43-3842-402-6218; Fax: +43-3842-402-6202. Received: 3 September 2012; in revised form: 19 October 2012 / Accepted: 19 October 2012 / Published: 30 October 2012 Abstract: A variety of platinum-group-minerals (PGM) have been found to occur associated with the chromitite and dunite layers in the Niquelândia igneous complex. Two genetically distinct populations of PGM have been identified corresponding to phases crystallized at high temperatures (primary), and others formed or modified during post-magmatic serpentinization and lateritic
    [Show full text]
  • Mineralisation in Layered Mafic-Ultramafic Intrusions
    1 Mineralisation in Layered Mafic-Ultramafic Intrusions 2 3 Hannah S. R. Hughes1, Jens C. Ø. Andersen1, Brian O’Driscoll2 4 1Camborne School of Mines, College of Engineering, Mathematics and Physical Sciences, University 5 of Exeter, Tremough Campus, Penryn, Cornwall, TR10 9FE, UK 6 2Department of Earth and Environmental Sciences, University of Manchester, Oxford Road, 7 Manchester, M13 9PL, UK 8 9 10 See Also: Economic Geology, Layered Intrusions, Igneous Rocks, Igneous Processes, Mining Geology, 11 Mantle, Mantle Plumes, Minerals: Sulphides. 12 13 1 14 1. Introduction 15 Mineral deposits form in mafic-ultramafic layered intrusions (LMI) through a variety of magmatic 16 processes. Chromium, platinum-group elements (PGE) and nickel (Ni) are almost exclusively extracted 17 from mafic-ultramafic rocks (Table 1). LMI also host metals such as gold (Au), copper (Cu), cobalt (Co), 18 vanadium (V), titanium (Ti) and scandium (Sc). Mafic-ultramafic rocks are major sources of dimension 19 stone and aggregate, and increasingly, carbon capture and storage may generate significant demands 20 for Mg-silicate (olivine and associated minerals). 21 Chromium, Ti and V are extracted from the oxide minerals chromite, ilmenite and titanomagnetite. 22 Economic concentrations require several tens of percent of the host minerals, and exploration can 23 therefore utilize remote sensing. Chromite is the only naturally-occurring source of Cr that can be 24 economically extracted (Table 1). Vanadium is extracted from titanomagnetite and titanium from 25 ilmenite (Table 1). In some mines, Fe is recovered as a by-product. Chromite forms exclusively in 26 primitive mafic-ultramafic rocks, while titanomagnetite and ilmenite are more common in the evolved 27 parts of LMI.
    [Show full text]
  • A Short Geological Review of the Bushveld Complex by R
    A Short Geological Review of the Bushveld Complex By R. P. Schouwstra and E. D. Kinloch Amplats Research Centre, PO Box 6540, Homestead, 1412, South Africa and C. A. Lee Amplats Geological Services, PO Box 62179, Marshalltown, Johannesburg, 2107, South Africa At present most of the worldwide supply of cooled slowly from molten magma, deep within platinum and palladium and the associated ele- the earth. Silicate minerals in fixed proportions ments is obtained from mines within four major crystallised and aggregated to form the final layered igneous intrusions. These are the Bushveld igneous rocks. The composition of the minerals Complex in South Africa, the Stillwater Complex changed with the slow drop in temperature in the in the U.S.A., the Great Dyke in Zimbabwe, and magma brought about by cooling. The first silicate the Noril’sk/Talnakh Complexes in Russia (1). minerals which crystallised and settled out are rich These layered intrusions consist of rocks which in magnesium and iron (the ‘mafic’ parts of the The location ofplatinum mines are as follows: A is RPM Amandelbult, U is RPM Union, R is RPM Rustenburg, L is Lebowa. P is PPRust, N is Northam, I is Impala and W/E is Western & Eastern Plats Fig. I Simplified geological map of the Bushveld Complex (2). The green shades represent the Bushveld rocks, the rose shades are the granitic cover rocks, the blue and brown shades represent the pre- and post-Bushveld rock^, respectively. The red circular shape near Rustenburg is the Pilanesberg alkali complex. E = eastern limb, W = western limb, N = northern or Potgietersrus limb;f are faults Plutinum MhLr Reu, 2000, 44, (1).
    [Show full text]
  • Mineral Chemistry of Chromite in the Mayville
    GS-3 Mineral chemistry of chromite in the Mayville intrusion: evidence for petrogenesis and linkage to the Bird River sill in the Neoarchean Bird River greenstone belt, southeastern Manitoba (parts of NTS 52L5, 6, 12) by X.M. Yang and H.P. Gilbert Yang, X.M. and Gilbert, H.P. 2014: Mineral chemistry of chromite in the Mayville intrusion: evidence for petrogenesis and linkage to the Bird River sill in the Neoarchean Bird River greenstone belt, southeastern Manitoba (NTS 52L5, 6, 12); in Report of Activities 2014, Manitoba Mineral Resources, Manitoba Geological Survey, p. 32–48. Summary Ni-Cu-PGE mineralization, in In 2014, the Manitoba Geological Survey com- accord with the widespread occurrence of contact-style pleted bedrock mapping in the northern arm of the Bird magmatic sulphide mineralization near the base of the River greenstone belt of the western Superior province, heterolithic breccia zone (HBZ) and at the basal contact southeastern Manitoba. The project aim was to provide of the intrusion. Furthermore, the MI is prospective for fundamental geoscientific information to assist mineral reef-style, stratiform PGE mineralization in transitional exploration, in particular for magmatic Ni–Cu–platinum and/or contact zones between major rock units, and for group element (PGE)–Cr mineralization associated with stratiform chromitite mineralization as demonstrated by mafic–ultramafic intrusions in the region. Because mafic– the presence of massive chromitite bands and disrupted ultramafic rocks are readily altered by deformation, meta- chromitite-pyroxenite layers within the HBZ. morphism, magmatism and related hydrothermal systems, their primary mineral assemblages and geochemical com- Introduction position are typically modified, requiring more robust In 2014, the Manitoba Geological Survey (MGS) geochemical techniques to ‘see through’ these effects.
    [Show full text]
  • Occurrence, Texture, and Classification of Igneous Rocks - Gezahegn Yirgu
    GEOLOGY – Vol. II - Occurrence, Texture, and Classification of Igneous Rocks - Gezahegn Yirgu OCCURRENCE, TEXTURE, AND CLASSIFICATION OF IGNEOUS ROCKS Gezahegn Yirgu Addis Ababa University, Ethiopia Keywords: crystal twinning, crystal zoning, extrusion, felsic, glass, intergrowth, intrusion, IUGS, lava, mafic, magma, mineral, modal composition (mode), normative composition (norm), nucleation, plutonic, polarizing microscope, pyroclast, texture, thin section, viscosity, volcanism Contents 1. Introduction 2. Mode of Occurrence of Igneous Rocks 2.1. Lava Flows and Domes 2.2. Pyroclastic Deposits 2.3. Intrusive Bodies 2.3.1. Plutons 2.3.2. Minor Intrusions 2.3.3. Layered Intrusions 3. Texture of Igneous Rocks 3.1. Crystal Nucleation and Growth 3.2. Common Igneous Textures 3.2.1. Crystallinity 3.2.2. Granularity 3.2.3. Crystal Shapes 3.2.4. Mutual Relations of Crystals (and Amorphous Materials) 4. Classification and Nomenclature of Igneous Rocks 4.1. Classification Scheme for Igneous Rocks 4.2. Principal Factors in Classification 4.2.1. Modal Mineralogy 4.2.2. Grain Size 4.2.3. Nomenclature 4.2.4. Chemical Classification 4.3. ClassificationUNESCO and Nomenclature of Plutonic– EOLSS Rocks 4.3.1. Ultramafic Rocks 4.3.2. Charnockitic Rocks 4.4. ClassificationSAMPLE and Nomenclature of Volcanic CHAPTERS Rocks 4.5. Classification and Nomenclature of Pyroclastic Rocks 4.6. Other Igneous Rock Groups Acknowledgements Glossary Bibliography Biographical Sketch ©Encyclopedia of Life Support Systems (EOLSS) GEOLOGY – Vol. II - Occurrence, Texture, and Classification of Igneous Rocks - Gezahegn Yirgu Summary In this article, the manner in which igneous rocks occur in nature is introduced, followed by a discussion of the general textural features and appearance of these rocks.
    [Show full text]
  • Origin of Chromitites in Layered Intrusions: Evidence from Chromite-Hosted Melt Inclusions from the Stillwater Complex
    Origin of chromitites in layered intrusions: Evidence from chromite-hosted melt inclusions from the Stillwater Complex Carl Spandler* Research School of Earth Sciences, Australian National University, Canberra 0200, Australia John Mavrogenes Research School of Earth Sciences, and Department of Earth and Marine Sciences, Australian National University, Canberra 0200, Australia Richard Arculus Department of Earth and Marine Sciences, Australian National University, Canberra 0200, Australia ABSTRACT 1993); and (5) assimilation of country rock by primitive magma (Ir- Chromitites from layered ma®c intrusions are of great eco- vine, 1975; Kinnaird et al., 2002). nomic importance, yet the origin of these deposits remains enig- The antiquity and slow cooling of most chromitite-bearing layered matic. We describe multiphase silicate inclusions trapped within intrusions have hindered our understanding of the genesis of chromi- chromite grains from the G chromitite seam of the Stillwater Com- tites and layered intrusions in general. The primary petrologic and geo- plex, Montana, United States. These inclusions are interpreted to chemical evidence that are crucial for determining the evolution of represent melt trapped during chromite growth and hence provide cumulate rocks are often removed during subsolidus reequilibration and information on chromitite formation. Most reheated inclusions subsequent hydrothermal alteration or metamorphism. Furthermore, the have variable quench textures and chemical compositions that are compositions of the parental magmas of these intrusionsÐcritical in- consistent with variable degrees of mixing between a high-Mg ba- formation for understanding chromitite formationÐremain poorly saltic parental magma and a Na-rich trondhjemitic melt. The tron- constrained. dhjemite is suggested to derive from partial melting of ma®c or Melt inclusion studies have been extensively used for investigat- ing volcanic systems, yet have largely been ignored by researchers of metasedimentary country rocks.
    [Show full text]
  • Stratiform Chromite Deposit Model
    Stratiform Chromite Deposit Model Chapter E of Mineral Deposit Models for Resource Assessment Scientific Investigations Report 2010–5070–E U.S. Department of the Interior U.S. Geological Survey COVER: Photograph showing outcropping of the Bushveld LG6 chromitite seam. Photograph courtesy of Klaus J. Schulz, U.S. Geological Survey. Stratiform Chromite Deposit Model By Ruth F. Schulte, Ryan D. Taylor, Nadine M. Piatak, and Robert R. Seal II Chapter E of Mineral Deposit Model for Resource Assessment Scientific Investigations Report 2010–5070–E U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2012 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Schulte, R.F., Taylor, R.D., Piatak, N.M., and Seal, R.R., II, 2012, Stratiform chromite deposit model, chap. E of Mineral deposit models for resource assessment: U.S.
    [Show full text]
  • Komatiitic Flows of the Pioneer Ultramafic Complex of the 3.3Ga
    Louisiana State University LSU Digital Commons LSU Master's Theses Graduate School 2008 Komatiitic flows of the pioneer ultramafic complex of the 3.3Ga Weltevreden Formation, Barberton Greenstone Belt, South Africa: stratigraphy, petrology, and geochemistry Marc Romain Cooper Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_theses Part of the Earth Sciences Commons Recommended Citation Cooper, Marc Romain, "Komatiitic flows of the pioneer ultramafic ompc lex of the 3.3Ga Weltevreden Formation, Barberton Greenstone Belt, South Africa: stratigraphy, petrology, and geochemistry" (2008). LSU Master's Theses. 1599. https://digitalcommons.lsu.edu/gradschool_theses/1599 This Thesis is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Master's Theses by an authorized graduate school editor of LSU Digital Commons. For more information, please contact [email protected]. KOMATIITIC FLOWS OF THE PIONEER ULTRAMAFIC COMPLEX OF THE 3.3GA WELTEVREDEN FORMATION, BARBERTON GREENSTONE BELT, SOUTH AFRICA: STRATIGRAPHY, PETROLOGY, AND GEOCHEMISTRY A Thesis Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College In partial fulfillment of the requirements for the degree of Master of Science in The Department of Geology and Geophysics by Marc Romain Cooper B.S., Louisiana State University, 2003 August, 2008 ACKNOWLEDGEMENTS The author wishes to thank Dr. Gary Byerly, the author’s major advisor, for his guidance, support, and patience throughout the project, for the opportunity to carry out the field study and guidance therein, and for his unparalleled support in many other endeavors at LSU and beyond.
    [Show full text]