Drone footage of a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
Todd Hoefen
Todd Hoefen is a Geophysicist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Spectroscopy and Hyperspectral Imaging of Critical Mineral Resources
Development and Validation of Hyperspectral Imager for Field and Lab Scanning
USGS High Resolution Spectral Library
Environmental Studies of the World Trade Center Area After the September 11, 2001 Attack
Geochemical data for carbonatite samples from the Mountain Pass rare earth element deposit, southeast California
HySpex by NEO VNIR-1800 and SWIR-384 imaging spectrometer radiance and reflectance data, with associated ASD FieldSpec® NG calibration data, collected at Cripple Creek Victor mine, Cripple Creek, Colorado, 2017
Spectroscopy of Expanded Vermiculite Products and Insulation
Corescan Hyperspectral Core Imager, Mark III system data collected for the characterization of mineral resources near Nabesna, Alaska, 2014-2016
Imaging spectrometer reflectance data, mineral predominance map, and white mica wavelength position map, Nabesna Quadrangle, Alaska
Whole rock, soil, sediment, x-ray diffraction, and electron microprobe analyses of samples from the Orange Hill-Bond Creek area, Nabesna Quadrangle, Alaska
Airborne imaging spectrometer data collected for characterizing mineral resources near Nabesna, Alaska, 2014
USGS Spectral Library Version 7 Data
Drone footage of a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
See the actual drone footage at: https://www.usgs.gov/media/videos/prescribed-burn-tall-timbers-research…
Footage of drone during a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
See the actual drone footage at: https://www.usgs.gov/media/videos/prescribed-burn-tall-timbers-research…
Footage of drone during a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
Hyperspectral (VNIR-SWIR) analysis of roll front uranium host rocks and industrial minerals from Karnes and Live Oak Counties, Texas Coastal Plain
VNIR-SWIR (400–2500 nm) reflectance measurements were made on the surfaces of various cores, cuttings and sample splits of sedimentary rocks from the Tertiary Jackson Group, and Catahoula, Oakville and Goliad Formations. These rocks vary in composition and texture from mudstone and claystone to sandstone and are known host rocks for roll front uranium occurrences in Karnes and Live Oak Counties, T
Multiscale hyperspectral imaging of hydrothermal alteration in Yellowstone National Park, USA
Mineral Mapping of the Battle Mountain District, Nevada, USA, Using AVIRIS-Classic and SpecTIR Inc. AisaFENIX 1K Imaging Spectrometer Datasets
Imaging spectroscopy for the detection, assessment and monitoring of natural and anthropogenic hazards
Characterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy
Application of imaging spectroscopy for mineral exploration in Alaska: A study over porphyry Cu deposits in the eastern Alaska Range
USGS Spectral Library Version 7
Multiscale hyperspectral imaging of the Orange Hill Porphyry Copper Deposit, Alaska, USA, with laboratory-, field-, and aircraft-based imaging spectrometers
Environmental implications of the use of sulfidic back-bay sediments for dune reconstruction — Lessons learned post Hurricane Sandy
Hyperspectral surveying for mineral resources in Alaska
Trace elements in stormflow, ash, and burned soil following the 2009 station fire in southern California
Mapping surficial minerals at high latitudes: The USGS 2014 imaging spectrometer data collection in Alaska
USGS Digital Spectral Library
References for material identification in remote sensing images. The library contains spectral reflectance data for of hundreds of materials, including minerals, vegetation, organic and volatile compounds, and man-made materials.
Science and Products
- Science
Spectroscopy and Hyperspectral Imaging of Critical Mineral Resources
Our project will characterize the primary critical minerals (minerals that contain critical elements in their base structure) that are not yet in the USGS Spectral Library. We propose to increase understanding of the spectral indicators of critical minerals using lab-based studies of hand specimens and drill core, hyperspectral field scanning, and hyperspectral images collected from aircraft.Development and Validation of Hyperspectral Imager for Field and Lab Scanning
The Mineral Resources Program has advanced methods of imaging spectroscopy (hyperspectral remote sensing) that are now used routinely by the earth science and remote sensing communities for mineral mapping, soil quality mapping, hazard mitigation, and other terrestrial and planetary applications. The USGS is highly qualified to advance this technology based on its world class expertise in mineral...USGS High Resolution Spectral Library
The USGS Spectral Library contains reflectance spectra, including samples of minerals, rocks, soils, physically constructed as well as mathematically computed mixtures, plants, vegetation communities, microorganisms, and man-made materials. The samples and spectra collected were assembled for the purpose of using spectral features for the remote detection of these and similar materials. The latest...Environmental Studies of the World Trade Center Area After the September 11, 2001 Attack
USGS scientists conducted a remote sensing and mineralogical characterization study of lower Manhattan around the WTC after the September 11, 2001 attack. - Data
Geochemical data for carbonatite samples from the Mountain Pass rare earth element deposit, southeast California
This data release contains whole-rock major, minor, and trace element geochemical data for carbonatite samples from the Mountain Pass rare earth element (REE) deposit located in southeastern California. The Mountain Pass deposit is the largest REE deposit in the United States and in 2021, produced 43,000 metric tons (expressed as rare-earth-oxide equivalent; U.S. Geological Survey, 2022). SamplesHySpex by NEO VNIR-1800 and SWIR-384 imaging spectrometer radiance and reflectance data, with associated ASD FieldSpec® NG calibration data, collected at Cripple Creek Victor mine, Cripple Creek, Colorado, 2017
HySpex by NEO (HySpex) VNIR-1800 and SWIR-384 imaging spectrometer radiance data were acquired on September 14, 2017 at the Cresson Pit of the Cripple Creek & Victor mine in Cripple Creek, Colorado. ASD FieldSpec® NG data were collected on September 13 and 14, 2017 at two calibration sites within the Cresson Pit imaged with the HySpex imaging spectrometers. The HySpex VNIR-1800 imaging spectrometeSpectroscopy of Expanded Vermiculite Products and Insulation
This dataset contains descriptions and analytical data (i.e., electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for unexpanded and expanded vermiculite samples. These data are provided for 52 samples of vermiculite attic insulation, horticultural products, aggregate, and packing materials derived from mines near Enoree, South Carolina; Libby,Corescan Hyperspectral Core Imager, Mark III system data collected for the characterization of mineral resources near Nabesna, Alaska, 2014-2016
Corescan Hyperspectral Core Imager Mark III (HCI-III) system data were acquired for hand samples, and subsequent billets made from the hand samples, collected during the U.S. Geological Survey (USGS) 2014, 2015, and 2016 field seasons in the Nabesna area of the eastern Alaska Range. This area contains exposed porphyry deposits and hand samples were collected throughout the region in support of theImaging 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 miAirborne imaging spectrometer data collected for characterizing mineral resources near Nabesna, Alaska, 2014
Imaging spectrometer (hyperspectral) data were collected using the HyMap sensor over the Nabesna Area of Interest (AOI) in the eastern Alaska Range, July 14 and July 21, 2014. The primary study area was a remote part of the eastern Alaska Range where porphyry deposits are exposed. The HyMap imaging spectrometer measured reflected sunlight in 126 narrow channels spanning the 0.4 to 2.5 micron wavelUSGS Spectral Library Version 7 Data
This data release provides the U.S. Geological Survey (USGS) Spectral Library Version 7 and all related documents. The library contains spectra measured with laboratory, field, and airborne spectrometers. The instruments used cover wavelengths from the ultraviolet to the far infrared (0.2 to 200 microns). Laboratory samples of specific minerals, plants, chemical compounds, and man-made materials w - Multimedia
Prescribed Burn — Tall Timbers Research Station, FL (Drone)Prescribed Burn — Tall Timbers Research Station, FL (Drone)Prescribed Burn — Tall Timbers Research Station, FL (Drone)
Drone footage of a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
Drone footage of a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
Prescribed Burn — Tall Timbers Research Station, FL (Footage of Drone)Prescribed Burn — Tall Timbers Research Station, FL (Footage of Drone)Prescribed Burn — Tall Timbers Research Station, FL (Footage of Drone)See the actual drone footage at: https://www.usgs.gov/media/videos/prescribed-burn-tall-timbers-research…
Footage of drone during a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
See the actual drone footage at: https://www.usgs.gov/media/videos/prescribed-burn-tall-timbers-research…
Footage of drone during a prescribed fire at Tall Timbers Research Station, Tallahassee, Florida (April 19, 2017).
- Publications
Filter Total Items: 109
Hyperspectral (VNIR-SWIR) analysis of roll front uranium host rocks and industrial minerals from Karnes and Live Oak Counties, Texas Coastal Plain
VNIR-SWIR (400–2500 nm) reflectance measurements were made on the surfaces of various cores, cuttings and sample splits of sedimentary rocks from the Tertiary Jackson Group, and Catahoula, Oakville and Goliad Formations. These rocks vary in composition and texture from mudstone and claystone to sandstone and are known host rocks for roll front uranium occurrences in Karnes and Live Oak Counties, T
AuthorsBernard E. Hubbard, Tanya J. Gallegos, Victoria G. Stengel, Todd M. Hoefen, Raymond F. Kokaly, Brent ElliottMultiscale hyperspectral imaging of hydrothermal alteration in Yellowstone National Park, USA
Imaging spectroscopy (hyperspectral imaging) data have mainly been used to map surface materials covering relatively small areas from airborne sensors over the past 20+ years. As part of the U.S. Geological Survey Integrated hyperspectral, geophysical and geochemical studies of Yellowstone National Park hydrothermal systems project, we have collected multiscale imaging spectrometer data includingAuthorsTodd M. Hoefen, Raymond F. Kokaly, Keith Eric Livo, John Michael Meyer, JoAnn HollowayMineral Mapping of the Battle Mountain District, Nevada, USA, Using AVIRIS-Classic and SpecTIR Inc. AisaFENIX 1K Imaging Spectrometer Datasets
Imaging spectroscopy (hyperspectral imaging) has been used to successfully map minerals at the outcrop, deposit, district, and regional scale. This contribution presents spectral-based mineral maps of the Battle Mountain mining district, Nevada, USA, generated using multi-scale airborne imaging and ground-based point spectrometers. Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) and AisaFEAuthorsJohn Michael Meyer, Elizabeth A. Holley, Raymond F. Kokaly, Gregg A. Swayze, Todd M. HoefenImaging spectroscopy for the detection, assessment and monitoring of natural and anthropogenic hazards
Natural and anthropogenic hazards have the potential to impact all aspects of society including its economy and the environment. Diagnostic data to inform decision-making are critical for hazard management whether for emergency response, routine monitoring or assessments of potential risks. Imaging spectroscopy (IS) has unique contributions to make via the ability to provide some key quantitativeAuthorsCindy Ong, Véronique Carrere, Sabine Chabrillat, Roger N. Clark, Todd M. Hoefen, Raymond F. Kokaly, Rodolphe Marion, Carlos Roberto de Souza Filho, Gregg A. Swayze, David R. ThompsonCharacterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy
Commercially produced vermiculite insulation from Libby, Montana, contains trace levels of asbestiform amphibole, which is known to cause asbestos-related diseases. When vermiculite insulation is found in a building, evaluation for its potential asbestos content traditionally involves collecting a sample from an attic or wall and submitting it for time-consuming analyses at an off-site laboratory.AuthorsGregg A. Swayze, Heather A. Lowers, William Benzel, Roger N. Clark, Rhonda L. Driscoll, Zac S. Perlman, Todd M. Hoefen, M. Darby DyarApplication 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. HubbardUSGS Spectral Library Version 7
We have assembled a library of spectra measured with laboratory, field, and airborne spectrometers. The instruments used cover wavelengths from the ultraviolet to the far infrared (0.2 to 200 microns [μm]). Laboratory samples of specific minerals, plants, chemical compounds, and manmade materials were measured. In many cases, samples were purified, so that unique spectral features of a material caAuthorsRaymond F. Kokaly, Roger N. Clark, Gregg A. Swayze, K. Eric Livo, Todd M. Hoefen, Neil C. Pearson, Richard A. Wise, William Benzel, Heather A. Lowers, Rhonda L. Driscoll, Anna J. KleinMultiscale 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. PrakashEnvironmental implications of the use of sulfidic back-bay sediments for dune reconstruction — Lessons learned post Hurricane Sandy
Some barrier-island dunes damaged or destroyed by Hurricane Sandy's storm surges in October 2012 have been reconstructed using sediments dredged from back bays. These sand-, clay-, and iron sulfide-rich sediments were used to make berm-like cores for the reconstructed dunes, which were then covered by beach sand. In November 2013, we sampled and analyzed partially weathered materials collected froAuthorsGeoffrey S. Plumlee, William Benzel, Todd M. Hoefen, Philip L. Hageman, Suzette A. Morman, Timothy J. Reilly, Monique Adams, Cyrus J. Berry, Jeffrey Fischer, Irene FisherHyperspectral 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. HubbardTrace elements in stormflow, ash, and burned soil following the 2009 station fire in southern California
Most research on the effects of wildfires on stream water quality has focused on suspended sediment and nutrients in streams and water bodies, and relatively little research has examined the effects of wildfires on trace elements. The purpose of this study was two-fold: 1) to determine the effect of the 2009 Station Fire in the Angeles National Forest northeast of Los Angeles, CA on trace elementAuthorsCarmen A. Burton, Todd M. Hoefen, Geoffrey S. Plumlee, Katherine L. Baumberger, Adam R. Backlin, Elizabeth Gallegos, Robert N. FisherMapping 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 Goldfarb - Web Tools
USGS Digital Spectral Library
References for material identification in remote sensing images. The library contains spectral reflectance data for of hundreds of materials, including minerals, vegetation, organic and volatile compounds, and man-made materials.
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