NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Effects of atmospheric moisture on rock resistivity.This study examines the changes in resistivity of rock samples as induced by atmospheric moisture. Experiments were performed on samples of hematitic sandstone, pyrite, and galena. The sandstone underwent a change in resistivity of four orders of magnitude when it was measured in a vacuum of 500 ntorr and in air of 37% relative humidity. Pyrite and galena showed no variations in resistivity when they were measured under the same conditions. These results, plus others obtained elsewhere, indicate that rocks of the resistive type are affected in their electrical properties by atmospheric moisture, whereas rocks of the conductive type are not. The experimental evidence obtained is difficult to reconcile with a model of aqueous electrolytic conduction on the sample surface. It is instead suggested that adsorbed water molecules alter the surface resistivity in a manner similar to that observed in semiconductors and insulators.
Document ID
19730044045
Document Type
Reprint (Version printed in journal)
Authors
Alvarez, R. (California, University Berkeley, Calif., United States)
Date Acquired
August 7, 2013
Publication Date
April 10, 1973
Publication Information
Publication: Journal of Geophysical Research
Volume: 78
Subject Category
GEOPHYSICS
Distribution Limits
Public
Copyright
Other