Accession Number : AD0780083

Title :   Visible and Near-Infrared Absorption Coefficients of Montmorillonite and Related Clays.

Descriptive Note : Research and development technical rept.,


Personal Author(s) : Gillespie,James B. ; Lindberg,James D. ; Smith,Michael S.

Report Date : MAY 1974

Pagination or Media Count : 17

Abstract : Estimates of the optical absorption coefficients for montmorillonite, hectorite, nontronite, metabentonite, illite, and attapulgite clay minerals were made by the application of diffuse reflectance spectroscopy in the spectral region from 0.4 to 2.4 micrometers. These clay minerals are weak absorbers over this spectral range, with the primary absorption occurring in the 1.4-micrometers and 1.9-micrometer water bands. Values of the absorption coefficients were on the order of 10 to 20/cm in the 1.4-micrometer band and 20 to 30/cm in the 1.9-micrometer band with the exception of the metabentonite, which gave an absorption coefficient of about 80/cm in the 1.9-micrometer band. The absorption coefficient increased rapidly as the near-ultraviolet region was approached. (Modified author abstract)

Descriptors :   *Clay, *Visible spectra, *Infrared spectra, *Aerosols, Near infrared radiation, Montmorillonite

Subject Categories : Atmospheric Physics
      Geology, Geochemistry and Mineralogy

Distribution Statement : APPROVED FOR PUBLIC RELEASE