Karen Duttweiler Kelley
Science and Products
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.
Critical Metals in Black Shales
Project objectives were to improve the understanding of critical mineral enrichment in black shales and improve accuracy of resource assessments.
Tectonic and magmatic controls on the metallogenesis of porphyry deposits in Alaska
Porphyry Cu and Mo deposits and occurrences are found throughout Alaska; they formed episodically during repeated subduction and arc-continent collisions spanning the Silurian to Quaternary. Porphyry systems occur in continental-margin and island arcs, which are broadly grouped into pre-accretionary or post-accretionary arcs. Pre-Mesozoic...
Kreiner, Douglas C.; Jones, James V.; Kelley, Karen D.; Graham, Garth E. Hydrogeochemistry in the Yukon-Tanana Upland region of east-central Alaska: Possible exploration tool for porphyry-style deposits
A hydrogeochemical study using high resolution ICP-MS was undertaken at the Taurus and other porphyry Cu-Mo(-Au) occurrences and Ag-Au-Cu (+/- Pb, Zn) occurrences with epithermal-style characteristics in the Yukon-Tanana upland region of eastern Alaska. Surface water samples were collected from 30 sites on creeks that drain known deposits and...
Kelley, Karen D.; Graham, Garth E.
Alkalic-type epithermal gold deposit model; Chapter R in Mineral deposit models for resource assessment
This report summarizes the primary characteristics of alkalic-type epithermal gold (Au) deposits and provides an updated descriptive model. These deposits, primarily of Mesozoic to Neogene age, are among the largest epithermal gold deposits in the world. Considered a subset of low-sulfidation epithermal deposits, they are spatially and genetically...
Kelley, Karen D.; Spry, Paul G.; McLemore, Virginia T.; Fey, David L.; Anderson, Eric D.
International geoscience collaboration to support critical mineral discovery
The importance of critical minerals and the need to expand and diversify critical mineral supply chains has been endorsed by the Federal governments of Australia, Canada, and the United States. The geoscience organizations of Geoscience Australia, the Geological Survey of Canada and the U.S. Geological Survey have created the Critical Minerals...
Evaluation of the analytical methods used to determine the elemental concentrations found in the stream geochemical dataset compiled for Alaska
A recent U.S. Geological Survey data compilation of stream-sediment geochemistry for Alaska contains decades of analyses collected under numerous Federal and State programs. The compiled data were determined by various analytical methods. Some samples were reanalyzed by a different analytical method than the original, resulting in some elements...
Wang, Bronwen; Ellefsen, Karl J.; Granitto, Matthew; Kelley, Karen D.; Karl, Susan M.; Case, George N.D.; Kreiner, Douglas C.; Amundson, Courtney L. Strategic and critical metals in produced geothermal fluids from Nevada and Utah
Herein we summarize the results of an investigation dealing with the concentrations and inventories of strategic, critical and valuable materials (SCVM) in produced fluids from geothermal and hydrocarbon reservoirs (50-250° C) in Nevada and Utah. Water samples were collected from thirty-four production wells across eight geothermal fields, the...
Simmons, Stuart F.; Kirby, Stephe H.; Verplanck, Philip L.; Kelley, Karen Duttweiler Sulfur isotopes of host strata for Howards Pass (Yukon–Northwest Territories) Zn-Pb deposits implicate anaerobic oxidation of methane, not basin stagnation
A new sulfur isotope stratigraphic profile has been developed for Ordovician-Silurian mudstones that host the Howards Pass Zn-Pb deposits (Canada) in an attempt to reconcile the traditional model of a stagnant euxinic basin setting with new contradictory findings. Our analyses of pyrite confirm the up-section 34S enrichment reported...
Johnson, Craig A.; Slack, John F.; Dumoulin, Julie A.; Kelley, Karen Duttweiler; Falck, Hendrik Multiscale hyperspectral imaging of the Orange Hill Porphyry Copper Deposit, Alaska, USA, with laboratory-, field-, and aircraft-based imaging spectrometers
In the past decade, use of hyperspectral imaging (imaging spectroscopy) for mineral exploration and mining operations has been increasing at different spatial scales. In this paper, we focus on recent trends in applying imaging spectrometer data to: 1) airborne imaging of high latitude deposits, 2) field-based imaging of outcrops, and 3)...
Kokaly, Raymond; Graham, Garth E.; Hoefen, Todd M.; Kelley, Karen D.; Johnson, Michaela R.; Hubbard, Bernard E.; Buchhorn, M.; Prakash, A.
Vanadium
Vanadium is used primarily in the production of steel alloys; as a catalyst for the chemical industry; in the making of ceramics, glasses, and pigments; and in vanadium redox-flow batteries (VRBs) for large-scale storage of electricity. World vanadium resources in 2012 were estimated to be 63 million metric tons, which include about 14 million...
Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.; Kelley, Karen D.; Scott, Clint; Polyak, Désirée E.; Kimball, Bryn E. The hyper-enrichment of V and Zn in black shales of the Late Devonian-Early Mississippian Bakken Formation (USA)
Black shales of the Late Devonian to Early Mississippian Bakken Formation are characterized by high concentrations of organic carbon and the hyper-enrichment (> 500 to 1000s of mg/kg) of V and Zn. Deposition of black shales resulted from shallow seafloor depths that promoted rapid development of euxinic conditions. Vanadium hyper-...
Scott, Clint; Slack, John F.; Kelley, Karen Duttweiler Transgressive-regressive cycles in the metalliferous, oil-shale-bearing Heath Formation (Upper Mississippian), central Montana
The Upper Mississippian Heath Formation, which accumulated in the Big Snowy Trough of central Montana, has been known for three decades to contain mudrocks highly enriched in Zn, V, Mo, Ni and other metals, and source rocks for oil. The unit has more recently been recognized as a prospective tight oil play. Here we present petrographic,...
Dumoulin, Julie A.; Johnson, Craig A.; Kelley, Karen D.; Botterell, Palma J.; Hackley, Paul C.; Scott, Clint; Slack, John F.
Hyperspectral surveying for mineral resources in Alaska
Alaska is a major producer of base and precious metals and has a high potential for additional undiscovered mineral resources. However, discovery is hindered by Alaska’s vast size, remoteness, and rugged terrain. New methods are needed to overcome these obstacles in order to fully evaluate Alaska’s geology and mineral resource...
Kokaly, Raymond F.; Graham, Garth E.; Hoefen, Todd M.; Kelley, Karen D.; Johnson, Michaela R.; Hubbard, Bernard E.