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Erin Marsh

Erin Marsh is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center.

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USGS science for a changing world

Mineral Resource Assessment Training

The USGS Mineral Resources Program conducts mineral resource assessments and is training USGS scientists in how to conduct these assessments for future work. As a practical exercise, the scientists will conduct an assessment for tungsten in the U.S.
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Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center
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Mineral Resource Assessment Training

The USGS Mineral Resources Program conducts mineral resource assessments and is training USGS scientists in how to conduct these assessments for future work. As a practical exercise, the scientists will conduct an assessment for tungsten in the U.S.
Learn More
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scientists in field looking at rocks

Tellurium in Igneous-related Epithermal Precious Metal Deposits in Colorado and New Mexico

The project aims to improve our understanding of the causes of tellurium enrichment in epithermal precious metal deposits, and strengthen our ability to assess the Nation's tellurium deposits. Tellurium is used in solar panel technologies and is considered a critical mineral. Epithermal deposits of this type represent a prospective future source of tellurium.
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Geology, Geophysics, and Geochemistry Science Center
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Tellurium in Igneous-related Epithermal Precious Metal Deposits in Colorado and New Mexico

The project aims to improve our understanding of the causes of tellurium enrichment in epithermal precious metal deposits, and strengthen our ability to assess the Nation's tellurium deposits. Tellurium is used in solar panel technologies and is considered a critical mineral. Epithermal deposits of this type represent a prospective future source of tellurium.
Learn More

Whole rock geochemical data from the eastern part of the Yukon-Tanana Upland region, Alaska, USA

This data release is part of a 2016-2019 study on the geology, geochemistry and geochronology of ore systems in the eastern Yukon-Tanana Upland region, Alaska. Whole rock chemistry was conducted on 185 samples, mostly from Au prospects, with lesser samples from porphyry Cu prospects. Geographically, most samples are from gold prospects near the Pogo Au mine and east to Black Mountain in the Big De
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Qualitative Mineral Potential Map of Tungsten Skarn in the Yukon-Tanana Uplands, Eastern Alaska, USA, 2021

This data release supports the paper titled, "Tungsten skarn potential of the Yukon-Tanana Uplands, Eastern Alaska, USA-A mineral resource assessment", published via open-access license in the Journal of Geochemical Exploration and available at: https://doi.org/10.1016/j.gexplo.2020.106700. The data release includes GIS data that map potential for tungsten skarn mineralization in permiss
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Alaska Science Center
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Early Neoproterozoic gold deposits of the Alto Guaporé province, southwestern Amazon craton, western Brazil

The Alto Guaporé gold province, southwestern Amazon craton, contains gold deposits that have been mined since the beginning of the 18th century and these deposits, together, have modern-day, pre-mining gold resources of at least 1.8 Moz. The ore is associated with quartz vein systems along the southeastern part of the Aguapei belt, a ~35-km-wide and ~500-km-long, NNW-trending shear zone formed due
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Geology, Geophysics, and Geochemistry Science Center

Late Jurassic-Early Cretaceous orogenic gold mineralization in the Klamath Mountains, California: Constraints from 40Ar/39Ar dating of hydrothermal muscovite

The Klamath Mountains gold province is the second most important historical producer in California, having produced more than 7 Moz of gold from both lode and placer sources. Hydrothermal muscovite grains from gold-bearing veins provide the first 40Ar/39Ar age constraints indicative of a protracted period of mineralization in the Klamath Mountains. The data indicate that the window for orogenic go
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Tungsten skarn potential of the Yukon-Tanana Upland, eastern Alaska, USA—A mineral resource assessment

Tungsten (W) is used in a variety of industrial and technological applications and has been identified as a critical mineral for the United States, India, the European Union, and other countries. These countries rely on W imports mostly from China, which leaves them vulnerable to supply disruption. Consequently, the U.S. government has a current initiative to understand domestic resource potential
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Mineral Resources Program, Geology, Energy & Minerals Science Center, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center

Geochemistry of hematite veins in IOA-IOCG deposits of SE Missouri, USA: Relation to felsic magmatism and caldera lakes

The paragenesis, textures, and chemical compositions of secondary hematite in regional potassic altered rhyolites, four IOA deposits, the sedimentary iron deposit at Pilot Knob and the Boss IOCG deposit in SE Missouri were determined and compared to primary magnetite from the IOA and IOCG deposits. Magnetite is composed of elements characteristics of mafic to intermediate intrusions whereas hemati
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Denver Microbeam Laboratory

Absence of magnetite microlites, geochemistry of magnetite veins and replacements in IOA deposits, SE Missouri, USA: Relations to intermediate intrusions

The paragenesis, textures, and chemical compositions of magnetite in two mafic to intermediate intrusions and four IOA deposits in SE Missouri were studied to discriminate between igneous and hydrothermal sources. In this study, we found that replacement magnetite with mineral inclusion-rich cores yields erroneously high Ti, Al, Si, Mg, and Mn contents as determined by EMP and LA-ICP-MS due to ru
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center, Denver Microbeam Laboratory

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.Scanning electron microscopy (SEM)-cathodoluminescence a
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

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, and Re. The generally poor data concerning trace elem
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Energy and Minerals Mission Area, Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

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 unconformably by impermeable shales and marls of t
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Energy and Minerals Mission Area, Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

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

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 exploration potential of the country. In 1999, the Minis
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Mineral Resources Program

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)

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 gabbro-anorthosite intrusive complexes in cratonic settings, op
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Database of mineral deposits in the Islamic Republic of Mauritania (phase V, deliverables 90 and 91)

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 control panel from which to easily navigate through th
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Mineral Resources Program, Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center

Mineral potential tracts for orogenic, Carlin-like, and epithermal gold deposits in the Islamic Republic of Mauritania, (phase V, deliverable 69)

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 deposit occurs along a shear zone in Middle Archean rock
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

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