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Science and Products
Mineral thermometry and fluid inclusion studies of the Pea Ridge iron oxide-apatite–rare earth element deposit, Mesoproterozoic St. Francois Mountains Terrane, southeast Missouri, USA
Mineral thermometry and fluid inclusion studies were conducted on variably altered and mineralized samples from the Mesoproterozoic Pea Ridge iron oxide-apatite (IOA)-rare earth element (REE) deposit in order to constrain P-T conditions, fluid chemistry, and the source of salt and volatiles during early magnetite and later REE mineralization....Hofstra, Albert H.; Meighan, Corey J.; Song, Xinyu; Samson, Iain; Marsh, Erin E.; Lowers, Heather A.; Emsbo, Poul; Hunt, Andrew G.
Critical elements in sediment-hosted deposits (clastic-dominated Zn-Pb-Ag, Mississippi Valley-type Zn-Pb, sedimentary rock-hosted Stratiform Cu, and carbonate-hosted Polymetallic Deposits): A review: Chapter 12
Some sediment-hosted base metal deposits, specifically the clastic-dominated (CD) Zn-Pb deposits, carbonate-hosted Mississippi Valley-type (MVT) deposits, sedimentary-rock hosted stratiform copper deposits, and carbonate-hosted polymetallic (“Kipushi type”) deposits, are or have been important sources of critical elements including Co, Ga, Ge,...Marsh, Erin E.; Hitzman, Murray W.; Leach, David L.
A salt diapir-related Mississippi Valley-type deposit: The Bou Jaber Pb-Zn-Ba-F deposit, Tunisia: Fluid inclusion and isotope study
The Bou Jaber Ba-F-Pb-Zn deposit is located at the edge of the Bou Jaber Triassic salt diapir in the Tunisia Salt Diapir Province. The ores are unconformity and fault-controlled and occur as subvertical column-shaped bodies developed in dissolution-collapse breccias and in cavities within the Late Aptian platform carbonate rocks, which are covered...Bouhlel, Salah; Leach, David; Johnson, Craig A.; Marsh, Erin E.; Salmi-Laouar, Sihem; Banks, David A.
Database of mineral deposits in the Islamic Republic of Mauritania (phase V, deliverables 90 and 91): Chapter S in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)
Three ore deposits databases from previous studies were evaluated and combined with new known mineral occurrences into one database, which can now be used to manage information about the known mineral occurrences of Mauritania. The Microsoft Access 2010 database opens with the list of tables and forms held within the database and a Switchboard...Marsh, Erin E.; Anderson, Eric D.
Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 69): Chapter H in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)
The gold resources of Mauritania presently include two important deposits and a series of poorly studied prospects. The Tasiast belt of deposits, which came into production in 2007, is located in the southwestern corner of the Rgueïbat Shield and defines a world-class Paleoproterozoic(?) orogenic gold ore system. The producing Guelb Moghrein...Goldfarb, Richard J.; Marsh, Erin E.; Anderson, Eric D.; Horton, John D.; Finn, Carol A.; Beaudoin, Georges
Mineral potential for nickel, copper, platinum group elements(PGE), and chromium deposits hosted in ultramafic rocks in the Islamic Republic of Mauritania (phase V, deliverable 67): Chapter G in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)
PRISM-I summary documents mention the presence of mafic-ultramafic igneous intrusive rocks in several areas of Mauritania and a number of chromium (Cr) and copper-nickel (Cu-Ni (±Co, Au)) occurrences associated with them. Permissive geologic settings generally include greenstone belts of any age, layered mafic-ultramafic and unlayered...Taylor, Cliff D.; Marsh, Erin E.; Anderson, Eric D.
Nickel-cobalt laterites: a deposit model: Chapter H in Mineral deposit models for resource assessment
Nickel-cobalt (Ni-Co) laterite deposits are supergene enrichments of Ni±Co that form from intense chemical and mechanical weathering of ultramafic parent rocks. These regolith deposits typically form within 26 degrees of the equator, although there are a few exceptions. They form in active continental margins and stable cratonic settings....Marsh, Erin E.; Anderson, Eric J.; Gray, Floyd
Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 68): Chapter H1 in Second projet de renforcement institutionnel du secteur minier de la République Islamique de Mauritanie (PRISM-II)
In 1996, at the request of the Government of the Islamic Republic of Mauritania, a team of U.S. Geological Survey (USGS) scientists produced a strategic plan for the acquisition, improvement and modernization of multidisciplinary sets of data to support the growth of the Mauritanian minerals sector and to highlight the geological and mineral...Goldfarb, Richard J.; Marsh, Erin E.; Horton, John D.
Mauritania – A greenfields exploration opportunity in northwestern Africa
No abstract available.Taylor, Cliff D.; Anderson, E.D.; Bradley, D.C.; Beaudoin, G.; Cosca, Michael A.; Eppinger, Robert G.; Fernette, Gregory L.; Finn, Carol A.; Friedel, Michael J.; Giles, Stuart A.; Goldfarb, Richard J.; Horton, John D.; Lee, Gregory K.; Marsh, Erin E.; Mauk, Jeffrey L.; Motts, Holly A. ; Ould El Joud, M. Y.; Ould Soueidatt, S.; Ould Taleb Mohamed, A.; Rockwell, Barnaby W.
Regional Fluid Flow and Basin Modeling in Northern Alaska
The foothills of the Brooks Range contain an enormous accumulation of zinc (Zn) in the form of zinc sulfide and barium (Ba) in the form of barite in Carboniferous shale, chert, and mudstone. Most of the resources and reserves of Zn occur in the Red Dog deposit and others in the Red Dog district; these resources and reserves surpass those of most...Kelley, Karen D.; Ayuso, Robert A.; Burruss, Robert; Dumoulin, Julie A.; Graham, Garth E.; Harris, Anita G.; Johnson, Craig A.; Kelley, Karen D.; Leach, David L.; Lillis, Paul G.; Marsh, Erin E.; Moore, Thomas E.; Potter, Christopher J.; Slack, John F.
The late cretaceous Donlin Creek gold deposit, Southwestern Alaska: Controls on epizonal ore formation
The Donlin Creek gold deposit, southwestern Alaska, has an indicated and inferred resource of approximately 25 million ounces (Moz) Au at a cutoff grade of 1.5 g/t. The ca. 70 Ma deposit is hosted in the Late Cretaceous Kuskokwim flysch basin, which developed in the back part of the arc region of an active continental margin, on previously...Goldfarb, Richard J.; Ayuso, Robert A.; Miller, Marti L.; Ebert, Shane W.; Marsh, Erin E.; Petsel, Scott A.; Miller, Lance D.; Bradley, Dwight C.; Johnson, Chad; McClelland, William C.