Observations from T-Phases from Pacific Earthquake Events: Implications for Seismic/Acoustic Coupling

Abstract

This report presents the results of a study of the coupling of seismic energy to the SOFAR channel and the propagation of acoustic energy from source to receiver. The results of an investigation of T-phase amplitude level vs. earthquake magnitude are presented for events in the Pacific ocean. The poor correlation between these parameters suggests that the generation of detectable T-phases is dependent not only upon event magnitude and depth, source mechanism, and transmission loss from source to receiver, but also on details of the source bathymetry which govern the coupling of seismic to acoustic energy. Despite the complexities of the data, several features of T-phase data that are readily observable are: (1) T-phase energy for submarine earthquakes drops off rapidly at frequencies greater than 16 Hz, and (2) that the nature of the T-phase coda is strongly dependent on the geographic source area, thus T-phases from the same area tend to be very similar.

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Document Details

Document Type
Technical Report
Publication Date
Nov 12, 1997
Accession Number
ADA341908

Entities

People

  • Catherin Degroot-hedlin
  • John A. Orcutt

Organizations

  • Scripps Institution of Oceanography

Tags

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Aleutian Islands
  • Amplitude
  • Atmospheric Sciences
  • Earth Sciences
  • Earthquakes
  • Frequency
  • Frequency Bands
  • Geographic Regions
  • Geography
  • Geophysics
  • Observation
  • Oceanography
  • Oceans
  • Planetary Sciences
  • Seabed

Fields of Study

  • Geology

Readers

  • Acoustical Oceanography.
  • Acoustics.
  • Geotechnical Engineering.