Accession Number:

ADA148589

Title:

Detailed Oceanic Crustal Modeling.

Descriptive Note:

Final rept. 1 Feb 81-31 May 84,

Corporate Author:

CALIFORNIA INST OF TECH PASADENA SEISMOLOGICAL LAB

Personal Author(s):

Report Date:

1984-11-07

Pagination or Media Count:

138.0

Abstract:

The research performed under this contract can be divided into 3 main topics changes in existing methods, Cagniard de-Hoop and WKBJ, which enable construction of synthetics for mixed path simulations use of long period SH waves with source in the Northwest Atlantic and receivers on the northeast coast of North America to derive an oceanic upper mantle shear velocity model and a technique based on evaluating the Kirchoff-Helmholtz integral for predicting the effect of near source or near receiver structure complexity on far field p waves. In Section II we assess the fact that recent models of upper mantle structure based on long period body waves WWSSN suggest large horizontal gradients, especially in shear velocities. Some changes in existing methods are required to construct synthetics for mixed path situations. This is accomplished by allowing locally dipping structure and making some modifications to generalized ray theory. In Section III, we have modeled the SH motion from earthquakes in the northwest Atlantic ocean to derive an oceanic upper mantle shear velocity model. In Section IV, we extend the Kirchoff-Helmholtz integral method to calculate acoustic potentials which transmit through three dimensional warped boundaries.

Subject Categories:

  • Physical and Dynamic Oceanography
  • Numerical Mathematics
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE