Accession Number : AD0767053

Title :   Preliminary Observations of the Microstructure of Nevada Test Site Tuffs.

Descriptive Note : Final rept.,

Corporate Author : TERRA TEK INC SALT LAKE CITY UTAH

Personal Author(s) : Swolfs,H. S. ; Pratt,H. R. ; Green,S. J. ; Jones,A. H.

Report Date : AUG 1973

Pagination or Media Count : 32

Abstract : Nevada Test site tuffs contain pores that range in size from several millimeters to 10 to the minus seventh power millimeters (angstrom) in diameter. Optical observation of thin sections and scanning electron microscope pictures show the pores to be distributed within pumice and crystal fragments, at the intersection of grain boundaries, and within the glassy matrix. While many of the larger pores are connected, many of the small pores (less than 0.001 millimeters in size) are occluded. Because of the variation in pore sizes, ordinary methods of determining wet, dry, and grain densities will not give total porosity, percent saturation and percent unfilled voids with a high degree of accuracy and precision. Furthermore, compaction of the tuffs will occur by collapse of pores of different sizes at different stress states, with some pores not closing until extremely high stresses. (Author)

Descriptors :   (*ROCK, MICROSTRUCTURE), POROSITY, NEVADA, COMPACTING

Subject Categories : Geology, Geochemistry and Mineralogy

Distribution Statement : APPROVED FOR PUBLIC RELEASE