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Gregg A Swayze, Ph.D.
Gregg Swayze is a Research Geophysicist 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.
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
1985 to present, U.S. Geological Survey, Denver, Colorado
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.
AGU, GSA, Colorado Scientific Society, and Society of Economic Geologists
Science and Products
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.
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...
Interactive website allowing users to search the contents of the USGS Spectral Library Version 7 data.
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.
Characterizing 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...Swayze, Gregg A.; Lowers, Heather A.; Benzel, William M.; Clark, Roger N.; Driscoll, Rhonda L.; Perlman, Zac S.; Hoefen, Todd M.; Dyar, M. Darby
Spectral properties of anhydrous carbonates and nitrates
No abstract available.Bishop, J.L.; King, S.J.; Lane, M.D.; Lafuente, B.; Brown, A.J.; Hiroi, T.; Swayze, Gregg A.; Lin, J.-F.
USGS 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...Kokaly, Raymond F.; Clark, Roger N.; Swayze, Gregg A.; Livo, K. Eric; Hoefen, Todd M.; Pearson, Neil C.; Wise, Richard A.; Benzel, William M.; Lowers, Heather A.; Driscoll, Rhonda L.; Klein, Anna J.
Discovery 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...Ehlmann, Bethany L.; Swayze, Gregg A.; Milliken, Ralph E.; Mustard, John F.; Clark, Roger N.; Murchie, Scott L.; Breit, George N.; Wray, James J.; Gondet, Brigitte; Poulet, Francois; Carter, John; Calvin, Wendy M.; Benzel, William M.; Seelos, Kimberly D.
Oil 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)...Sun, Shaojie; Hu, Chuanmin; Feng, Lian; Swayze, Gregg A.; Holmes, Jamie; Graettinger, George; MacDonald, Ian R.; Garcia, Oscar; Leifer, Ira
Spectroscopy from Space: Chapter 10
No abstract availableClark, Roger N.; Swayze, Gregg A.; Carlson, Robert R.; Grundy, Will; Noll, Keith
Natural 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...MacDonald, Ian R.; 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; Swayze, Gregg A.
Spectral properties of Ca-sulfates: Gypsum, bassanite, and anhydrite
This study of the spectral properties of Ca-sulfates was initiated to support remote detection of these minerals on Mars. Gypsum, bassanite, and anhydrite are the currently known forms of Ca-sulfates. They are typically found in sedimentary evaporites on Earth, but can also form via reaction of acidic fluids associated with volcanic activity....Bishop, Janice L.; Lane, Melissa D.; Dyar, M. Darby; King, Sara J.; Brown, Adrian J.; Swayze, Gregg A.
Mapping advanced argillic alteration at Cuprite, Nevada, using imaging spectroscopy
Mineral maps based on Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) data were used to study late Miocene advanced argillic alteration at Cuprite, Nevada. Distributions of Fe-bearing minerals, clays, micas, sulfates, and carbonates were mapped using the Tetracorder spectral-shape matching system. The Al content of white micas increases...Swayze, Gregg A.; Clark, Roger N.; Goetz, Alexander F.H.; Livo, K. Eric; Breit, George N.; Kruse, Fred A.; Sutley, Stephen J.; Snee, Lawrence W.; Lowers, Heather A.; Post, James L.; Stoffregen, Roger E.; Ashley, Roger P.
Science applications of a multispectral microscopic imager for the astrobiological exploration of Mars
Future astrobiological missions to Mars are likely to emphasize the use of rovers with in situ petrologic capabilities for selecting the best samples at a site for in situ analysis with onboard lab instruments or for caching for potential return to Earth. Such observations are central to an understanding of the potential for...Nunez, Jorge; Farmer, Jack; Sellar, R. Glenn; Swayze, Gregg A.; Blaney, Diana L.
State of the art satellite and airborne marine oil spill remote sensing: Application to the BP Deepwater Horizon oil spill
The vast and persistent Deepwater Horizon (DWH) spill challenged response capabilities, which required accurate, quantitative oil assessment at synoptic and operational scales. Although experienced observers are a spill response's mainstay, few trained observers and confounding factors including weather, oil emulsification, and scene...Leifer, Ira; Lehr, William J.; Simecek-Beatty, Debra; Bradley, Eliza; Clark, Roger N.; Dennison, Philip E.; Hu, Yongxiang; Matheson, Scott; Jones, Cathleen E; Holt, Benjamin; Reif, Molly; Roberts, Dar A.; Svejkovsky, Jan; Swayze, Gregg A.; Wozencraft, Jennifer M.
Aqueous mineralogy and stratigraphy at and around the proposed Mawrth Vallis MSL Landing Site: New insights into the aqueous history of the region
In this work, we have confirmed the mineralogical stratigraphy previously inferred by other authors, but also demonstrate the presence of additional minerals, including a possible acid-leaching product near the top of the sequence, an Mh-OH bearing phyllosilicate at the to of the sequence, and potentially a Ca-sulfate at the bottom of the...Dobrea, Eldar Z. Noe; Michalski, Joseph; Swayze, Gregg
This shows the spectral signature (left) of the mineral topaz (right).
This shows the spectral signature (left) of plywood (right).
U.S. Geological Survey scientists and partners have created an onsite, time-saving technique for building inspectors to ascertain whether vermiculite insulation contains amphibole asbestos. The findings are featured in the April 2 edition of American Mineralogist.
We've got a library full of spectral signatures, like a police fingerprint library for minerals and other substances!