Gregg Swayze is a Scientist Emeritus in Denver. Gregg received a Doctorate in Geology from the University of Colorado in 1997. Since joining the USGS in 1985, Gregg has devoted his career to studying Remote Sensing and specializes in Imaging Spectroscopy. Presently, his science focuses on environmental and mineral exploration applications of imaging spectroscopy.
Research Interests
Over the years, Gregg has developed methods to spectrally map acid-mine drainage in Leadville, Colorado, naturally-occurring asbestos in the foothills of California, insulation asbestos in the World Trade Center dust, and oil emulsions formed during the 2010 BP oil spill. He has also developed a portable spectral fingerprinting technique to identify asbestos-bearing vermiculite in attic insulation. Gregg has used his imaging spectroscopy experience with relict hydrothermal systems in Nevada and Hawaii to help map similar mineral deposits on the surface of Mars with the NASA CRISM orbital spectrometer. His most recent focus is on spectrally mapping REE-bearing minerals at the Mt. Pass Mine in California. He was recently selected as a Co-Investigator of the NASA/JPL Earth Surface Mineral Dust Source Investigation (EMIT) team with the goal of putting an imaging spectrometer on the International Space Station to map the mineralogy of dust source regions on a global basis.
Professional Experience
1985 to present, U.S. Geological Survey, Denver, Colorado
Education and Certifications
Ph.D. degree/Geology, University of Colorado, 1997
M.S. degree/Geology, Colorado School of Mines, 1985
B.S. degree/Geology, Grand Valley State University, 1982
Affiliations and Memberships*
American Geophysical Union
Geological Society of America
Colorado Scientific Society
Society of Economic Geologists
Science and Products
Spectroscopy and Hyperspectral Imaging of Critical Mineral Resources
Using In Situ IR Spectroscopy Measurements of Vermiculite Insulation to Determine Its Origin
Spectroscopy and Principles of Spectroscopy
Extensive tutorial on reflectance spectroscopy, the causes of absorption bands, the absorption and scattering processes that occur when light encounters a particulate surface, and principles of spectroscopy including continuum analysis, grain size effects, mixtures, etc.
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
Spectroscopy of Expanded Vermiculite Products and Insulation
USGS Spectral Library Version 7 Data
Mineral Mapping of the Battle Mountain District, Nevada, USA, Using AVIRIS-Classic and SpecTIR Inc. AisaFENIX 1K Imaging Spectrometer Datasets
Quantifying uncertainty for remote spectroscopy of surface composition
Classification of oil spill by thicknesses using multiple remote sensors
Imaging spectroscopy for the detection, assessment and monitoring of natural and anthropogenic hazards
Isotopic ratios of Saturn's rings and satellites: Implications for the origin of water and Phoebe
Spatial spectroscopic models for remote exploration
Characterizing the source of potentially asbestos-bearing commercial vermiculite insulation using in situ IR spectroscopy
Spectral properties of anhydrous carbonates and nitrates
USGS Spectral Library Version 7
Discovery of alunite in Cross crater, Terra Sirenum, Mars: Evidence for acidic, sulfurous waters
Oil slick morphology derived from AVIRIS measurements of the Deepwater Horizon oil spill: Implications for spatial resolution requirements of remote sensors
Natural and unnatural oil slicks in the Gulf of Mexico
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.Using In Situ IR Spectroscopy Measurements of Vermiculite Insulation to Determine Its Origin
The goal of this study was to determine if in situ near-infrared reflectance measurements, using portable spectrometers, could be used to reliably identify the source of vermiculite ore and therefore its potential to contain asbestos. The method developed can be used to determine vermiculite insulation's source and estimate its potential amphibole content, providing low-cost analysis with onsite...Spectroscopy and Principles of Spectroscopy
Extensive tutorial on reflectance spectroscopy, the causes of absorption bands, the absorption and scattering processes that occur when light encounters a particulate surface, and principles of spectroscopy including continuum analysis, grain size effects, mixtures, etc.
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). SamplesSpectroscopy 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,USGS 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
- Publications
Filter Total Items: 71
Mineral 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. HoefenQuantifying uncertainty for remote spectroscopy of surface composition
Remote surface measurements by imaging spectrometers play an important role in planetary and Earth science. To make these measurements, investigators calibrate instrument data to absolute units, invert physical models to estimate atmospheric effects, and then determine surface properties from the spectral reflectance. This study quantifies the uncertainty in this process. Global missions demand prAuthorsDavid R. Thompson, Amy Braverman, Philip Brodrick, Alberto Candela, Nimrod Carmon, Roger N. Clark, David Connelly, Robert O. Green, Raymond F. Kokaly, Longlei Li, Natalie Mahowald, Ronald L. Miller, Gregory S. Okin, Thomas H. Painter, Gregg A. Swayze, Michael Turmon, Jouni Susilouto, David WettergreenClassification of oil spill by thicknesses using multiple remote sensors
Satellite Synthetic Aperture Radar (SAR) is an operational tool for monitoring and assessment of oil spills. Satellite SAR has primarily been used to detect the presence/absence of oil, yet its ability to discriminate oil emulsions within a detected oil slick has not been fully exploited. Additionally, one of the challenges in the past has been the ability to deliver strategic information derivedAuthorsOscar Garcia-Pineda, Gordon Staples, Cathleen E Jones, Chuanmin Hu, Benjamin Holt, Villy Kourafalou, George Graettinger, Lisa DiPinto, Ellen Ramirez, David Street, Jay Cho, Gregg A. Swayze, Shaojie Sun, Diana Garcia, Francisco Haces-GarciaImaging 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. ThompsonIsotopic ratios of Saturn's rings and satellites: Implications for the origin of water and Phoebe
Isotopic ratios have long been used to learn about physical processes acting over a wide range of geological environments, and in constraining the origin and/or evolution of planetary bodies. We report the spectroscopic detection of deuterium in Saturn's rings and satellites, and use these measurements to determine the (D/H) ratios in their near-surface regions. Saturn's moons, Phoebe and Iapetus,AuthorsRoger N. Clark, Robert H. Brown, D.P. Cruikshank, Gregg A. SwayzeSpatial spectroscopic models for remote exploration
Ancient hydrothermal systems are a high-priority target for a future Mars sample return mission because they contain energy sources for microbes and can preserve organic materials (Farmer, 2000; MEPAG Next Decade Science Analysis Group, 2008; McLennan et al.,2012; Michalski et al.,2017). Characterizing these large, heterogeneous systems with a remote explorer is difficult due to communications banAuthorsDavid R. Thompson, Alberto Candela, David Wettergreen, E. Noe Dobrea, Gregg A. Swayze, Roger N Clark, Rebecca GreenbergerCharacterizing 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 DyarSpectral properties of anhydrous carbonates and nitrates
No abstract available.AuthorsJ.L. Bishop, S.J. King, M.D. Lane, B. Lafuente, A. J. Brown, T. Hiroi, Gregg A. Swayze, J.-F. LinUSGS 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. KleinDiscovery of alunite in Cross crater, Terra Sirenum, Mars: Evidence for acidic, sulfurous waters
Cross crater is a 65 km impact crater, located in the Noachian highlands of the Terra Sirenum region of Mars (30°S, 158°W), which hosts aluminum phyllosilicate deposits first detected by the Observatoire pour la Minéralogie, L’Eau, les Glaces et l’Activitié (OMEGA) imaging spectrometer on Mars Express. Using high-resolution data from the Mars Reconnaissance Orbiter, we examine Cross crater’s basinAuthorsBethany L. Ehlmann, Gregg A. Swayze, Ralph E. Milliken, John F. Mustard, Roger N. Clark, Scott L. Murchie, George N. Breit, James J. Wray, Brigitte Gondet, Francois Poulet, John Carter, Wendy M. Calvin, William Benzel, Kimberly D. SeelosOil slick morphology derived from AVIRIS measurements of the Deepwater Horizon oil spill: Implications for spatial resolution requirements of remote sensors
Using fine spatial resolution (~ 7.6 m) hyperspectral AVIRIS data collected over the Deepwater Horizon oil spill in the Gulf of Mexico, we statistically estimated slick lengths, widths and length/width ratios to characterize oil slick morphology for different thickness classes. For all AVIRIS-detected oil slicks (N = 52,100 continuous features) binned into four thickness classes (≤ 50 μm but thickAuthorsShaojie Sun, Chuanmin Hu, Lian Feng, Gregg A. Swayze, Jamie Holmes, George Graettinger, Ian R. MacDonald, Oscar Garcia, Ira LeiferNatural and unnatural oil slicks in the Gulf of Mexico
When wind speeds are 2 – 10 m s−1, reflective contrasts in the ocean surface make oil slicks visible to synthetic aperture radar (SAR) under all sky conditions. Neural network analysis of satellite SAR images quantified the magnitude and distribution of surface oil in the Gulf of Mexico from persistent, natural seeps and from the Deepwater Horizon (DWH) discharge. This analysis identified 914 natuAuthorsIan R. MacDonald, O. Garcia-Pineda, A. Beet, S. Daneshgar Asl, L. Feng, D. G. Graettinger, D. French-McCay, J. Holmes, C. Hu, F. Huffer, I. Leifer, F. Mueller-Karger, A. Solow, M. Silva, Gregg A. Swayze - 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.
- News
*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