Visible and Near-Infrared Absorption Coefficients of Montmorillonite and Related Clays.
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)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1974
- Accession Number
- AD0780083
Entities
People
- James B. Gillespie
- James D. Lindberg
- Michael S. Smith
Organizations
- United States Army Communications-Electronics Command