Upper Mantle Q and Transmission Studies Using LASA and WWSS Data.

Abstract

Studies related to the crust and upper-mantle structure beneath the Montana LASA support the idea that the source of seismic time delays at the array includes the upper mantle. A study of the crustal transfer-ratio at LASA shows the complexity of ratio spectra for models concerned principally with the crust are not complex enough to fit actual data from the array. Thus, structure in the upper-mantle is suggested. A study of the earth's isostatic response to a concentrated load, which makes no a priori assumptions concerning the mechanism of compensation, suggests compensation is more complicated than the Heiskanen, Pratt, or Airy mechanisms would suggest and extends well into the upper mantle. A long-range seismic refraction study along the axis of the Rocky Mountains supports a double M-discontinuity. (Author)

Document Details

Document Type
Technical Report
Publication Date
Oct 10, 1972
Accession Number
AD0753110

Entities

People

  • Joseph F. Gettrust
  • Robert P. Meyer

Organizations

  • University of Wisconsin–Madison

Tags

DTIC Thesaurus Topics

  • Compensation
  • Diffraction
  • Discontinuities
  • Mountains
  • Refraction
  • Rocky Mountains
  • Spectra

Readers

  • Seismology