Link to USGS home page

Preliminary Report on Using Imaging Spectroscopy to Map Ultramafic Rocks, Serpentinites, and Tremolite-Actinolite-Bearing Rocks in California

By Gregg A. Swayze1, Chris T. Higgins2, John P. Clinkenbeard2, Raymond F. Kokaly1, Roger N. Clark1, Gregory P. Meeker1, and Stephen J. Sutley1

1U.S. Geological Survey, MS964 Box 25046, Denver Federal Center, Denver, Colo. 80225
2California Department of Conservation, California Geological Survey, 801 K Street, MS 13-40, Sacramento, Calif. 95814
Open-File Report 2004–1304
Version 1.0
Published 2004
Airborne Visible/InfraRed Imaging Spectrometer (AVIRIS) data were collected in approximately 3-kilometer-wide swaths over selected areas in El Dorado and Plumas Counties that contain serpentinite and ultramafic rocks as part of an experiment to determine if potentially asbestos-bearing rocks could be identified spectrally. Mineral maps created from the AVIRIS data were used successfully to delineate exposures of serpentine and tremolite-actinolite/talc in areas with up to 70 percent vegetation cover in some cases. In other cases, the density of vegetation is so high that it prevented spectral identification by AVIRIS of minerals in those areas, thus there may be more serpentine and tremolite-actinolite/talc present than is shown on the mineral maps.

The text of this report is presented here in Portable Document Format. The latest version of Adobe Acrobat Reader or similar software is required to view it. If you wish to download the latest version of Acrobat Reader free of charge, click here .

Downloading Suggestion:

It is best to download a large PDF file to your hard drive rather than open it inside your browser. (A standard click may automatically open the PDF file inside the browser but doing so will result in a very slow load.)
For guidance on how to do this, go to [].

Downloading the PDF file may take several moments but will be worth the wait. Once it is downloaded, open the PDF from your hard drive using Adobe Acrobat—it will open in a fraction of the time it would take to open the PDF over the Internet.

Full Report, including figures.
(This version of the report is accessible as defined in Section 508.)
Text-Only version of the report.
Location of AVIRIS low-altitude flight lines
Flagstaff Hill mineral map
Details of Iron Mountain area
Garden Valley mineral map
Little Bald Mountain mineral map
Details of Bear Creek Quarry area
Red Hill mineral map
Details of Red Hill mineral map
Reflectance spectra of vibrational absorptions of some minerals
Scanning electron micrograph of chrysotile fibers in a hand sample
Scanning elecron micrograph of chrysotile fibers on non-fibrous grain logo