Accession Number : AD0753850

Title :   Crustal Structure from a High-Resolution Seismic Refraction Profile Across the Basin and Range-Middle Rocky Mountains Transition Zone.

Descriptive Note : Progress rept. 1 May 71-30 Apr 72,

Corporate Author : UTAH UNIV SALT LAKE CITY DEPT OF GEOLOGICAL AND GEOPHYSICAL SCIENCES

Personal Author(s) : Smith,R. B. ; Braile,L. W. ; Keller,G. R. ; Welch,R. M.

Report Date : 15 DEC 1972

Pagination or Media Count : 45

Abstract : A high-resolution seismic refraction profile using large open-pit quarry blasts as sources, has been recorded along a line which crosses the Basin and Range-Middle Rocky Mountains provinces boundary. Interpretation of these data and existing USGS refraction lines in the region indicates that crustal thickness and upper mantle P-wave velocity increase to the east of the boundary. The increase in crustal thickness does not occur at the boundary between physiographic provinces but begins about 50 km east of the Wasatch front. A crustal low velocity layer located between 10 and 15 km in depth is continuous from the Basin and Range province into the Middle Rocky Mountains. The velocity contrast between the low velocity layer and the overlying granitic layer decreases to the east. (Author)

Descriptors :   (*LITHOSPHERE, *STRUCTURAL GEOLOGY), THICKNESS, ANOMALIES, VELOCITY, DEPTH FINDING, GRANITE, REPORTS, UNITED STATES, SEISMIC WAVES, REFRACTION, MOUNTAINS

Subject Categories : Geology, Geochemistry and Mineralogy
      Seismology

Distribution Statement : APPROVED FOR PUBLIC RELEASE