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Susan Karl

Sedimentology, stratigraphy, tectonics, geochemistry, and economic geology of southeast Alaska

Professional Experience

  • 1977-Present Research Geologist, USGS Alaska Science Center, Anchorage, AK

  • 1976 Earth Science Associates, Palo Alto, CA

  • 1975 WGM mining, Brooks Range, AK

  • 1974 Rio Tinto mining, Wrangell Mts, AK

Education and Certifications

  • Ph.D. 1982 Stanford University

  • Classes 1975-1976 University of Alaska Fairbanks

  • B.A. 1973 Middlebury College

Affiliations and Memberships*

  • Fellow: Geological Soc. America, Geological Assoc. Canada

  • Member: American Geophysical Union, American Assoc. Petrol. Geol.

  • President: Alaska Geological Society

Honors and Awards

  • UAF 1976

  • Shell grants 1978, 1980

  • GSA Harold Stearns best student proposal award 1978

  • USGS achievement 1979

  • Sigma XI grants1980, 1981

  • GSA grant 1981

  • UNESCO grant 1986

  • USGS star 1999

Science and Products

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Map of Alaska showing estimated mineral-resource potential

GIS Prospectivity Analysis for Critical Minerals in Ore-Forming Systems in Alaska

Alaska is dominated by a history of tectonic events that foster mobilization and concentration of a wide variety of mineral commodities that are critical to the US economy and are vital to national defense, renewable-energy, and emerging electronics technologies.
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Mineral Resources Program, Alaska Science Center
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GIS Prospectivity Analysis for Critical Minerals in Ore-Forming Systems in Alaska

Alaska is dominated by a history of tectonic events that foster mobilization and concentration of a wide variety of mineral commodities that are critical to the US economy and are vital to national defense, renewable-energy, and emerging electronics technologies.
Learn More
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Darby Mountain outcrop of quartz monzonite towards the contact between the pluton and Paleozoic marbles

Petrology, Tectonic Setting, and Potential for Concentration of Rare Earth Elements (REE) and High Field Strength Elements (HFSE) in the High-K Darby and Kachauik Plutons, Seward Peninsula, Alaska

One of the geologic environments that host rare earth and other critical and strategic element deposits are alkaline intrusive rocks.
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Mineral Resources Program, Alaska Science Center
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Petrology, Tectonic Setting, and Potential for Concentration of Rare Earth Elements (REE) and High Field Strength Elements (HFSE) in the High-K Darby and Kachauik Plutons, Seward Peninsula, Alaska

One of the geologic environments that host rare earth and other critical and strategic element deposits are alkaline intrusive rocks.
Learn More

Data for Uranium-Lead Geochronology, Carbon and Sulfur Stable Isotopes, and Raman Spectroscopy from Graphite Creek, Alaska

This data release supports the paper titled, "Insights into the metamorphic history and origin of flake graphite mineralization at the Graphite Creek graphite deposit, Seward Peninsula, Alaska, USA", published in the journal Mineralium Deposita. The data release includes zircon and titanite U-Pb-Thisotope and age data, monazite U-Pb-Th isotope, trace element and age data, carbon and sulfur stablei
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Alaska Science Center

Whole Rock Major and Trace Element Chemistry for Igneous Rocks from Tyonek, Lime Hills, Talkeetna, McGrath, and Lake Clark Quadrangles, Western Alaska Range, Alaska

This data release contains whole rock major and trace element data for 69 igneous rock samples collected from the Western Alaska Range between 2011 and 2012. The Series field relates to chronological units discussed in Jones et al. (2021, Geosphere) and Todd et al. (2022 IN PREP). Descriptions are from original collector notebooks and are provided here for informational purposes only.
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Alaska Science Center

Whole Rock Major and Trace Element Chemistry for Igneous and Sedimentary Rocks from the Western Alaska Range, Alaska

This data release contains whole rock major and trace element data for 399 igneous and sedimentary rock samples collected from the Western Alaska Range between 1968 and 2014 and funded by the Mineral Resources Program of the U.S. Geological Survey. All materials were analyzed by ALS Global, between 2014 and 2018, by a range of different techniques, so multiple unique entries for a given element re
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Alaska Science Center

Data from the Chemical Analysis of Archived Stream-Sediment Samples, Alaska

This data release contains the elemental concentration data for more than 1700 archived stream-sediment samples collected in Alaska. Samples were retrieved from the USGS Mineral Program's sample archive in Denver, CO, and the Alaska Division of Geological and Geophysical Surveys Geologic Materials Center in Anchorage, AK. All samples were analyzed using a multi-element analytical method involving
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Alaska Science Center

Data and results for GIS-based identification of areas that have resource potential for lode gold deposits in Alaska

This data release contains the analytical results and evaluated source data files of geospatial analyses for identifying areas in Alaska that may be prospective for different types of lode gold deposits, including orogenic, reduced-intrusion-related, epithermal, and gold-bearing porphyry. The spatial analysis is based on queries of statewide source datasets of aeromagnetic surveys, Alaska Geochemi
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Alaska Science Center

Geochemical and 40Ar/39Ar Analytical Data of Rocks from Glacier Bay National Park and Preserve

This data set contains major and trace element geochemical data and 40Ar/39Ar isotopic data and ages for rock samples collected during 2016 fieldwork in Glacier Bay National Park and Preserve. The plutonic rock samples were collected for radiometric age determinations to test for the presence of the Late Jurassic to Early Cretaceous (130-160 Ma) Saint Elias suite. The age analyses indicate that al
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Alaska Science Center

U-Pb Isotopic Data and Ages of Zircon and Titanite from Rocks from the Western Alaska Range, Northern Aleutian Range, Taylor Mountains, and Tikchik Mountains Regions, Alaska

This data set contains U-Pb isotopic data and ages of zircon and titanite from igneous and metamorphic rocks collected from the western Alaska and northern Aleutian Range of south-central Alaska. The data sets also contain U-Pb isotopic data and ages of detrital zircon from sedimentary and metasedimentary rocks collected in the same region but also from the Taylor and Wood River Mountains of south
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Alaska Science Center

U-Pb Isotopic Data and Ages of Titanite and Detrital Zircon from Selected Rocks from the Western Alaska Range, Alaska

This data set contains U-Pb isotopic data and associated ages of titanite from one sample and detrital zircon grains from 33 sedimentary and metasedimentary rocks collected from the western Alaska Range in south-central Alaska. The samples were collected as part of geological mapping and research conducted between 2010 and 2014 and funded by the Mineral Resources Program of the U.S. Geological Sur
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Alaska Science Center

Alaska Geochemical Database Version 3.0 (AGDB3) including best value data compilations for rock, sediment, soil, mineral, and concentrate sample media

The Alaska Geochemical Database Version 3.0 (AGDB3) contains new geochemical data compilations in which each geologic material sample has one best value determination for each analyzed species, greatly improving speed and efficiency of use. Like the Alaska Geochemical Database Version 2.0 before it, the AGDB3 was created and designed to compile and integrate geochemical data from Alaska to facilit
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Mineral Resources Program, Geology, Geophysics, and Geochemistry Science Center

Geologic Map of Baranof Island, southeastern Alaska

This map updates the geology of Baranof Island based on fieldwork, petrographic analyses, paleontologic ages, and isotopic ages. These new data provide constraints on depositional and metamorphic ages of lithostratigraphic rock units and the timing of structures that separate them. Kinematic analyses and thermobarometric calculations provide insights on the regional tectonic processes that affecte
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Groundwater and Streamflow Information Program, Mineral Resources Program, Alaska Science Center, Subduction Zone Science

Maps and preliminary interpretation of anomalous rock geochemical data from the Petersburg quadrangle and parts of Port Alexander, Sitka, and Sumdum quadrangles, southeastern Alaska

Maps and preliminary interpretation of anomalous rock geochemical data from the Petersburg quadrangle and parts of the Port Alexander, Sitka, and Sumdum quadrangles, southeastern Alaska

No abstract available.

Mineral-resource map of the Petersburg quadrangle and parts of the Port Alexander, Sitka, and Sumdum quadrangles, southeastern Alaska

No abstract available.

Geologic map of western Chichagof and Yakobi islands, southeastern Alaska

No abstract available.

Reconnaissance geologic map of the Western Chichagof and Yakobi Islands wilderness study area, southeastern Alaska

No abstract available.
Two scientists next to 4x4 vehicle and buckets. Gravel-rock hill, tire tracks in mud, green trees, blue sky in background.
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Uhler Creek
Scientist kneeling to collect samples from tin placer tailings. Yellow tube, trowel, buckets near water, dirt and rocks.
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Cassiterite Creek
Placer tailings with rocks and vegetation covered mounds in foreground. A large mining dredge in right corner and cloudy sky.
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Dredge
Heavy equipment tire tracks between two blue buckets. Scientists digging, equipment, placer tailings and water in background.
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Clear Creek
Scientist in orange shirt and hat with gold pan in hands. Seven buckets scattered around shallow creek and small hills.
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Chicken Creek
geologist standing at bench recording data on graphite mineralization from core samples from the Graphite Creek deposit in Nome, Alaska
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USGS geologist recording data on graphite mineralization in core sample
Geologist stands in front of an entrance to an underground mine wearing an orange vest with pockets and rubber boots.
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Evidence of previous exploration
View of fog and clouds in the Aaron Creek valley with tail of R66 helicopter in right foreground.
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View of fog and clouds in the Aaron Creek valley, Alaska
Geologist approaches an old exploration trench on the east flank of Marsha Peak in the Stikine River corridor, Alaska
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USGS Geologist approaches an old exploration trench
Rock hammer in foreground shows meter-scale width of a felsic sill and helicopter is behind rock outcrop in the Stikine River corridor, Alaska
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Rock hammer shows meter-scale width of a felsic sill
Helicopter perched on outcrop to pick up USGS geologist with samples.
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USGS geologist approaches helicopter with samples
USGS geologist breaks mineralized rocks for examination and sample collection. Snow on slopes behind geologist.
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USGS geologist breaks mineralized rocks for examination and sample collection
Scientist examining geologic outcrop
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Geologist examines rocks at Darby Pluton, AK
Rock with phenocrysts and hammer for scale
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Potassium feldspar phenocrysts in syenite
Scintillometer sitting on top of a rock outcropping surrounded by trees
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Torrs of the Ruby Batholith
USGS scientist leaning against a rock outcropping with trees in the background
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Shearing of the Melozitna Granite
Scientists taking soil samples
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Taking soil samples
Image shows a woman sitting on a rock in a stream
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Panning for Rare Earths
Filter Total Items: 62

Insights into the metamorphic history and origin of flake graphite mineralization at the Graphite Creek graphite deposit, Seward Peninsula, Alaska, USA

Graphite Creek is an unusual flake graphite deposit located on the Seward Peninsula, Alaska, USA. We present field observations, uranium-lead (U–Pb) monazite and titanite geochronology, carbon (C) and sulfur (S) stable isotope geochemistry, and graphite Raman spectroscopy data from this deposit that support a new model of flake graphite ore genesis in high-grade metamorphic environments. The Graph
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George N. D. Case, Susan M. Karl, Sean P. Regan, Craig A. Johnson, Eric T Ellison, Jonathan Caine, Christopher Holm-Denoma, Laura Pianowski, Jeff A. Benowitz
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Mineral Resources Program, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center

Geospatial analysis delineates lode gold prospectivity in Alaska

Comprehensive, data-driven geographic information system analyses utilize publicly available lithologic, geochemical, geophysical, and mineral occurrence datasets to delineate gold resource potential in Alaska. These prospectivity analyses successfully identify areas containing known lode gold occurrences, expand areas of high prospectivity around known occurrences, improve the precision of deline
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Susan M. Karl, Douglas C. Kreiner, George N. D. Case, Keith A. Labay
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Ecosystems Mission Area, Alaska Science Center

GIS-based identification of areas that have resource potential for lode gold in Alaska

Several comprehensive, data-driven geographic information system (GIS) analyses were conducted to assess prospectivity for lode gold in Alaska. These analyses use available geospatial datasets of lithologic, geochemical, mineral occurrence, and geophysical data to build models for recognizing different types of gold deposits within physiographic units defined by stream drainage basins that are app
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Susan M. Karl, Douglas C. Kreiner, George N. D. Case, Keith A. Labay, Nora B. Shew, Matthew Granitto, Bronwen Wang, Eric D. Anderson
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Ecosystems Mission Area, Energy and Minerals Mission Area, Mineral Resources Program, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center

Chemical analysis of archived stream-sediment samples, Alaska

Geochemical data are presented for more than 1,500 archived stream-sediment samples and accompanying quality control samples. The archived sediments were reanalyzed to improve the stream geochemical dataset for Alaska and to support ongoing U.S. Geological Survey (USGS) studies. Sediment samples were primarily from the USGS Mineral Resources Program’s sample archive in Denver, Colorado, but a few
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Bronwen Wang, George N. D. Case, Mathew Granitto, Keith A. Labay, Nora B. Shew, Andrew D. Ingraham, Jaime S. Azain, Zachary C. Bueghly, Susan M. Karl, Karen D. Kelley
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Mineral Resources Program, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center

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 having concentrations reported by multiple analytical
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Bronwen Wang, Karl J. Ellefsen, Matthew Granitto, Karen D. Kelley, Susan M. Karl, George N. D. Case, Douglas C. Kreiner, Courtney L. Amundson
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Ecosystems Mission Area, Alaska Science Center

Detrital zircon geochronology along a structural transect across the Kahiltna assemblage in the western Alaska Range: Implications for emplacement of the Alexander-Wrangellia-Peninsular terrane against North America

The Kahiltna assemblage in the western Alaska Range consists of deformed Upper Jurassic and Cretaceous clastic strata that lie between the Alexander-Wrangellia-Peninsular (AWP) terrane to the south, and the Farewell and other peri-cratonic terranes to the north. Differences in detrital zircon populations and sandstone petrography allow geographic separation of the strata into two different success
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Stephen E. Box, Susan M. Karl, James V. Jones, Dwight C. Bradley, Peter J. Haeussler, Paul B. O'Sullivan
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Ecosystems Mission Area, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Alaska Geochemical Database Version 3.0 (AGDB3)—Including “Best Value” Data Compilations for Rock, Sediment, Soil, Mineral, and Concentrate Sample Media

The Alaska Geochemical Database Version 3.0 (AGDB3) contains new geochemical data compilations in which each geologic material sample has one “best value” determination for each analyzed species, greatly improving speed and efficiency of use. Like the Alaska Geochemical Database Version 2.0 before it, the AGDB3 was created and designed to compile and integrate geochemical data from Alaska to facil
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Matthew Granitto, Bronwen Wang, Nora B. Shew, Susan M. Karl, Keith A. Labay, Melanie B. Werdon, Susan S. Seitz, John E. Hoppe
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Mineral Resources Program, Alaska Science Center, Geology, Geophysics, and Geochemistry Science Center

Geospatial analysis identifies critical mineral-resource potential in Alaska

Alaska consists of more than 663,000 square miles (1,717,000 square kilometers) of land—more than a sixth of the total area of the United States—and large tracts of it have not been systematically studied or sampled for mineral-resource potential. Many regions of the State are known to have significant mineral-resource potential, and there are currently six operating mines in the State along with
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Susan M. Karl, Keith A. Labay
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Energy and Minerals Mission Area, Groundwater and Streamflow Information Program, Mineral Resources Program, Alaska Science Center

Regional patterns of Mesozoic-Cenozoic magmatism in western Alaska revealed by new U-Pb and 40Ar/39Ar ages

In support of regional geologic framework studies, we obtained 50 new argon-40/argon-39 (40Ar/39Ar) ages and 33 new uranium-lead (U-Pb) ages from igneous rocks of southwestern Alaska. Most of the samples are from the Sleetmute and Taylor Mountains quadrangles; smaller collections or individual samples are from the Bethel, Candle, Dillingham, Goodnews Bay, Holy Cross, Iditarod, Kantishna River, Lak

Authors
Dwight C. Bradley, Marti L. Miller, Richard M. Friedman, Paul W. Layer, Heather A. Bleick, James V. Jones, Steven E. Box, Susan M. Karl, Nora B. Shew, Timothy S. White, Alison B. Till, Julie A. Dumoulin, Thomas K. Bundtzen, Paul B. O'Sullivan, Thomas D. Ullrich
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Ecosystems Mission Area, Natural Hazards Mission Area, Groundwater and Streamflow Information Program, Mineral Resources Program, Volcano Hazards Program, Alaska Science Center, Volcano Science Center, Subduction Zone Science

The Peters Hills basin, a Neogene wedge-top basin on the Broad Pass thrust fault, south-central Alaska

The Neogene Peters Hills basin is a small terrestrial basin that formed along the south flank of the Alaska Range during a time in which there was regional shortening. The formation of the Peters Hills basin is consistent with it being a wedge-top basin that formed on top of the active southeast-vergent Broad Pass thrust fault. Movement along this thrust raised a ridge of Jurassic and Cretaceous m
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Peter J. Haeussler, Richard W. Saltus, Richard G. Stanley, Natalia Ruppert, Kristen Lewis, Susan M. Karl, Adrian M. Bender
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Groundwater and Streamflow Information Program, Alaska Science Center

GIS-based identification of areas that have resource potential for critical minerals in six selected groups of deposit types in Alaska

Alaska has considerable potential for undiscovered mineral resources. This report evaluates potential for undiscovered critical minerals in Alaska. Critical minerals are those for which the United States imports more than half of its total supply and which are largely derived from nations that cannot be considered reliable trading partners. In this report, estimated resource potential and certaint
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Groundwater and Streamflow Information Program, Alaska Science Center

Volcanogenic massive sulphide and orogenic gold deposits of northern southeast Alaska

This five-day field trip visits the most significant mineral deposits in northern southeast Alaska. The trip begins and ends with regional transects in the interior Intermontane terranes around Whitehorse, Yukon, and the Insular terranes along the northern Chatham Strait region of southeast Alaska (Fig. A-1 and Fig. A-2; Plate-1). To put the deposits in a regional tectonic framework, the guidebook
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Patrick J Sack, Susan M. Karl, Nathan Steeves, J Bruce Gemmell
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Groundwater and Streamflow Information Program, Alaska Science Center
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Geologic Map of Baranof Island, Southeastern Alaska Now Online

ANCHORAGE, Alaska — In the 20th century, Baranof Island in Southeastern Alaska has drawn attention for its gold, chrome and nickel deposits, timber...

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Science and Products

*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government