Garth E Graham
Garth Graham is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Filter Total Items: 14
Imaging spectrometer reflectance data, mineral predominance map, and white mica wavelength position map, Nabesna Quadrangle, Alaska
Approximately 1,900 square kilometers of imagery were collected from July 14 to July 21, 2014 using a HyMap sensor (Cocks and others, 1998) mounted on a modified Piper Navajo aircraft. The survey area covered parts of the Wrangell and Nutzotin Mountains in the eastern Alaska Range near Nabesna, Alaska. The aircraft was flown at an altitude of approximately 5,050 meters (m) (3,480 m above the mean
Whole rock, soil, sediment, x-ray diffraction, and electron microprobe analyses of samples from the Orange Hill-Bond Creek area, Nabesna Quadrangle, Alaska
This data release includes geochemical, x-ray diffraction mineralogical, and electron probe microanalysis (EPMA) data on rocks, soils, and sediments collected near the Orange Hill and Bond Creek porphyry copper deposits, Nabesna quadrangle, Alaska. Geochemical analyses were completed by a laboratory under contract with the U.S. Geological Survey (USGS). Electron microprobe and x-ray diffraction mi
Filter Total Items: 32
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 occurrences formed in continental or island arcs prior to a
Authors
Douglas C. Kreiner, James V. Jones, Karen D. Kelley, Garth E. Graham
Cretaceous to Oligocene magmatic and tectonic evolution of the western Alaska Range: Insights from U-Pb and 40Ar/39Ar geochronology
New U-Pb and 40Ar/39Ar ages integrated with geologic mapping and observations across the western Alaska Range constrain the distribution and tectonic setting of Cretaceous to Oligocene magmatism along an evolving accretionary plate margin in south-central Alaska. These rocks were emplaced across basement domains that include Neoproterozoic to Jurassic carbonate and siliciclastic strata of the Fare
Authors
James V. Jones, Erin Todd, Stephen E. Box, Peter J. Haeussler, Christopher Holm-Denoma, Susan M. Karl, Garth E. Graham, Dwight C. Bradley, Andrew R.C. Kylander-Clark, Richard M. Friedman, Paul W. Layer
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 occurrences and surrounding presumably unmineralized ar
Authors
Karen D. Kelley, Garth E. Graham
Application of imaging spectroscopy for mineral exploration in Alaska: A study over porphyry Cu deposits in the eastern Alaska Range
The U.S. Geological Survey tested the utility of imaging spectroscopy (also referred to as hyperspectral remote sensing) as an aid to regional mineral exploration efforts in remote parts of Alaska. Airborne imaging spectrometer data were collected in 2014 over unmined porphyry Cu deposits in the eastern Alaska Range using the HyMap™ sensor. Maps of the distributions of predominant minerals, made b
Authors
Garth E. Graham, Raymond F. Kokaly, Karen D. Kelley, Todd M. Hoefen, Michaela Johnson, Bernard E. Hubbard
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) laboratory-level imaging of geologic samples. Comparing mine
Authors
Raymond F. Kokaly, Garth E. Graham, Todd M. Hoefen, Karen D. Kelley, Michaela R. Johnson, Bernard E. Hubbard, M. Buchhorn, A. Prakash
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 potential. Hyperspectral surveying is one method that can be used to ra
Authors
Raymond F. Kokaly, Garth E. Graham, Todd M. Hoefen, Karen D. Kelley, Michaela R. Johnson, Bernard E. Hubbard
Mapping surficial minerals at high latitudes: The USGS 2014 imaging spectrometer data collection in Alaska
Passive optical remote sensing of high latitude regions faces many challenges including a short acquisition season and poor illumination due to low solar elevation. Additional complications are encountered in the identification of surface minerals for mineral resource characterization because minerals of interest commonly are exposed on steep terrain, further challenging reflectance retrieval and
Authors
Raymond F. Kokaly, Todd M. Hoefen, Garth Graham, Karen Kelly, Michaela Johnson, Bernard Hubbard, Richard Goldfarb
Geospatial compilation of results from field sample collection in support of mineral resource investigations, Western Alaska Range, Alaska, July 2013
This Data Series summarizes results from July 2013 sampling in the western Alaska Range near Mount Estelle, Alaska. The fieldwork combined in situ and camp-based spectral measurements of talus/soil and rock samples. Five rock and 48 soil samples were submitted for quantitative geochemical analysis (for 55 major and trace elements), and the 48 soils samples were also analyzed by x-ray diffraction
Authors
Michaela R. Johnson, Garth E. Graham, Bernard E. Hubbard, William Benzel
Hydrogeochemical exploration: a reconnaissance study on northeastern Seward Peninsula, Alaska
A reconnaissance hydrogeochemical study employing high-resolution/high-sensitivity inductively coupled plasma mass spectrometry analysis of stream and seep water samples (n= 171) was conducted in an area of limited bedrock exposure on the northeastern Seward Peninsula, Alaska. Sampling was focused in drainages around four main areas—at the Anugi Pb-Zn-Ag occurrence and in streams upstream of histo
Authors
Garth E. Graham, Ryan D. Taylor, Steve Buckley
Targeting Cu–Au and Mo resources using multi-media exploration geochemistry: An example from Tyonek Quadrangle, Alaska Range, Alaska
Regional stream and pond sediment, panned concentrate, and water sampling at and around known mineral occurrences in the Tyonek quadrangle, Alaska Range, Alaska were undertaken to determine geochemical signatures in the different media. For sediment samples, two different size fractions (− 80 mesh and − 230 mesh) were analyzed. Elevated concentrations (mostly ~ 2 × median) of elements such as As,
Authors
Garth E. Graham, Ryan D. Taylor, Gregory K. Lee, Dick Tripp
Timing of ore-related magmatism in the western Alaska Range, southwestern Alaska
This report presents isotopic age data from mineralized granitic plutons in an area of the Alaska Range located approximately 200 kilometers to the west-northwest of Anchorage in southwestern Alaska. Uranium-lead isotopic data and trace element concentrations of zircons were determined for 12 samples encompassing eight plutonic bodies ranging in age from approximately 76 to 57.4 millions of years
Authors
Ryan D. Taylor, Garth E. Graham, Eric D. Anderson, David Selby
Tectonic evolution and Cretaceous gold metallogenesis of southwestern Alaska
Cretaceous gold metallogenesis in southwestern Alaska comprises three distinct episodes related to the accretionary evolution of northwestern North America. The oldest mineralizing event is characterized by 112 Ma Cu-Au-Bi-Te porphyry-type(?) veining in the zoned Bonanza and adjacent plutons that intruded rocks of the Nyac terrane. Tectonic reconstructions and limited geological and geochemical da
Authors
Garth E. Graham, Richard J. Goldfarb, Marti L. Miller, Kati Gibler, Mike Roberts
Science and Products
- Science
- Data
Filter Total Items: 14
Imaging spectrometer reflectance data, mineral predominance map, and white mica wavelength position map, Nabesna Quadrangle, Alaska
Approximately 1,900 square kilometers of imagery were collected from July 14 to July 21, 2014 using a HyMap sensor (Cocks and others, 1998) mounted on a modified Piper Navajo aircraft. The survey area covered parts of the Wrangell and Nutzotin Mountains in the eastern Alaska Range near Nabesna, Alaska. The aircraft was flown at an altitude of approximately 5,050 meters (m) (3,480 m above the meanWhole rock, soil, sediment, x-ray diffraction, and electron microprobe analyses of samples from the Orange Hill-Bond Creek area, Nabesna Quadrangle, Alaska
This data release includes geochemical, x-ray diffraction mineralogical, and electron probe microanalysis (EPMA) data on rocks, soils, and sediments collected near the Orange Hill and Bond Creek porphyry copper deposits, Nabesna quadrangle, Alaska. Geochemical analyses were completed by a laboratory under contract with the U.S. Geological Survey (USGS). Electron microprobe and x-ray diffraction mi - Maps
- Publications
Filter Total Items: 32
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 occurrences formed in continental or island arcs prior to aAuthorsDouglas C. Kreiner, James V. Jones, Karen D. Kelley, Garth E. GrahamCretaceous to Oligocene magmatic and tectonic evolution of the western Alaska Range: Insights from U-Pb and 40Ar/39Ar geochronology
New U-Pb and 40Ar/39Ar ages integrated with geologic mapping and observations across the western Alaska Range constrain the distribution and tectonic setting of Cretaceous to Oligocene magmatism along an evolving accretionary plate margin in south-central Alaska. These rocks were emplaced across basement domains that include Neoproterozoic to Jurassic carbonate and siliciclastic strata of the FareAuthorsJames V. Jones, Erin Todd, Stephen E. Box, Peter J. Haeussler, Christopher Holm-Denoma, Susan M. Karl, Garth E. Graham, Dwight C. Bradley, Andrew R.C. Kylander-Clark, Richard M. Friedman, Paul W. LayerHydrogeochemistry 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 occurrences and surrounding presumably unmineralized arAuthorsKaren D. Kelley, Garth E. GrahamApplication of imaging spectroscopy for mineral exploration in Alaska: A study over porphyry Cu deposits in the eastern Alaska Range
The U.S. Geological Survey tested the utility of imaging spectroscopy (also referred to as hyperspectral remote sensing) as an aid to regional mineral exploration efforts in remote parts of Alaska. Airborne imaging spectrometer data were collected in 2014 over unmined porphyry Cu deposits in the eastern Alaska Range using the HyMap™ sensor. Maps of the distributions of predominant minerals, made bAuthorsGarth E. Graham, Raymond F. Kokaly, Karen D. Kelley, Todd M. Hoefen, Michaela Johnson, Bernard E. HubbardMultiscale 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) laboratory-level imaging of geologic samples. Comparing mineAuthorsRaymond F. Kokaly, Garth E. Graham, Todd M. Hoefen, Karen D. Kelley, Michaela R. Johnson, Bernard E. Hubbard, M. Buchhorn, A. PrakashHyperspectral 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 potential. Hyperspectral surveying is one method that can be used to raAuthorsRaymond F. Kokaly, Garth E. Graham, Todd M. Hoefen, Karen D. Kelley, Michaela R. Johnson, Bernard E. HubbardMapping surficial minerals at high latitudes: The USGS 2014 imaging spectrometer data collection in Alaska
Passive optical remote sensing of high latitude regions faces many challenges including a short acquisition season and poor illumination due to low solar elevation. Additional complications are encountered in the identification of surface minerals for mineral resource characterization because minerals of interest commonly are exposed on steep terrain, further challenging reflectance retrieval andAuthorsRaymond F. Kokaly, Todd M. Hoefen, Garth Graham, Karen Kelly, Michaela Johnson, Bernard Hubbard, Richard GoldfarbGeospatial compilation of results from field sample collection in support of mineral resource investigations, Western Alaska Range, Alaska, July 2013
This Data Series summarizes results from July 2013 sampling in the western Alaska Range near Mount Estelle, Alaska. The fieldwork combined in situ and camp-based spectral measurements of talus/soil and rock samples. Five rock and 48 soil samples were submitted for quantitative geochemical analysis (for 55 major and trace elements), and the 48 soils samples were also analyzed by x-ray diffractionAuthorsMichaela R. Johnson, Garth E. Graham, Bernard E. Hubbard, William BenzelHydrogeochemical exploration: a reconnaissance study on northeastern Seward Peninsula, Alaska
A reconnaissance hydrogeochemical study employing high-resolution/high-sensitivity inductively coupled plasma mass spectrometry analysis of stream and seep water samples (n= 171) was conducted in an area of limited bedrock exposure on the northeastern Seward Peninsula, Alaska. Sampling was focused in drainages around four main areas—at the Anugi Pb-Zn-Ag occurrence and in streams upstream of histoAuthorsGarth E. Graham, Ryan D. Taylor, Steve BuckleyTargeting Cu–Au and Mo resources using multi-media exploration geochemistry: An example from Tyonek Quadrangle, Alaska Range, Alaska
Regional stream and pond sediment, panned concentrate, and water sampling at and around known mineral occurrences in the Tyonek quadrangle, Alaska Range, Alaska were undertaken to determine geochemical signatures in the different media. For sediment samples, two different size fractions (− 80 mesh and − 230 mesh) were analyzed. Elevated concentrations (mostly ~ 2 × median) of elements such as As,AuthorsGarth E. Graham, Ryan D. Taylor, Gregory K. Lee, Dick TrippTiming of ore-related magmatism in the western Alaska Range, southwestern Alaska
This report presents isotopic age data from mineralized granitic plutons in an area of the Alaska Range located approximately 200 kilometers to the west-northwest of Anchorage in southwestern Alaska. Uranium-lead isotopic data and trace element concentrations of zircons were determined for 12 samples encompassing eight plutonic bodies ranging in age from approximately 76 to 57.4 millions of yearsAuthorsRyan D. Taylor, Garth E. Graham, Eric D. Anderson, David SelbyTectonic evolution and Cretaceous gold metallogenesis of southwestern Alaska
Cretaceous gold metallogenesis in southwestern Alaska comprises three distinct episodes related to the accretionary evolution of northwestern North America. The oldest mineralizing event is characterized by 112 Ma Cu-Au-Bi-Te porphyry-type(?) veining in the zoned Bonanza and adjacent plutons that intruded rocks of the Nyac terrane. Tectonic reconstructions and limited geological and geochemical daAuthorsGarth E. Graham, Richard J. Goldfarb, Marti L. Miller, Kati Gibler, Mike Roberts