Sedimentary rocks from the Racetrack Valley
area of Death Valley National Monument were
sampled, and spectral reflectance data in the
wavelengths 0.40 to 2.50 microns were obtained to
study the possibility of distinguishing different
carbonate rocks using the spectral data. Of the 49
samples which were analyzed, 12 were primarily
limestone, 25 were primarily dolomite, 7 were
primarily quartzite and one was a calcareous shale.
Spectra were obtained from pieces of the weathered
rock surfaces of the sample using a Beckmann Lab
Spectrophotometer.
This study shows that it is possible to
discriminate among carbonate rock types in this
study area using differing reflectivities, position
of various absorption bands and the presence of, or
lack of, different absorption bands such as
carbonate, water and hydroxyl. Dolomite absorption
bands were at slightly shorter wavelengths than
th9se of limestones. The exact position of the
absorption bands depended on other impurities in
the rock. The spectral reflectance of the
quartzites varied depending on the amount of desert
varnish covering the surface of the sample.
Different formations were discriminated as
well, using differing reflectivities, position of
various absorption bands and the presence of, or
lack of, different absorption bands such as
carbonate, water and hydroxyl bands.
The ability to discriminate both rock
carbonate types and rock formations will prove
invaluable to the field and exploration geologist.
Previously unaccessible territories will become
accessible using spectral reflectivity data and
remote sensing techniques. This will allow the
mapping and exploration of unexplored areas to be
more cost and time effective than previously
possible.
Description:
Includes bibliographical references (pages 143-149)
California State University, Northridge. Department of Geological Sciences.