Accession Number : AD0639679

Title :   CRUSTAL STRUCTURE IN WESTERN CANADA.

Descriptive Note : Final rept., 1 May 63-30 Apr 66,

Corporate Author : ALBERTA UNIV EDMONTON DEPT OF PHYSICS

Personal Author(s) : Cumming,G. L. ; Kanasewich,E. R.

Report Date : 30 JUN 1966

Pagination or Media Count : 194

Abstract : The report deals with crustal seismic refraction and reflection measurements in Western Canada. Evidence is presented to support three major layers in the crust below the sediments, with velocities of 6.1, 6.5 and 7.2 kilometers per second, overlying the upper mantle with velocity close to 8.2 kilometers per second. The total crustal thickness is about 45 kilometers. Refraction measurements indicate substantial lateral velocity variations in the crust, and these are related to large variations in the gravity field. Preliminary data suggest the presence of a low velocity layer in the upper mantle at a depth of about 120 kilometers. Reflection measurements indicate that a strong reflecting horizon is present at a depth close to the top of the 7.2 kilometer per second layer, and this reflector appears to be continuous over distances of several tens of kilometers. (Author)

Descriptors :   (*STRUCTURAL GEOLOGY, *CANADA), (*SEISMOLOGY, CANADA), UNDERGROUND EXPLOSIONS, SEISMIC WAVES, PROPAGATION, VELOCITY, SEISMOGRAPHS, STRATIGRAPHY, MAPPING, GEOPHYSICS

Subject Categories : Geology, Geochemistry and Mineralogy
      Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE