An Investigation of Attenuation, Scattering and Site Effects on Regional Phases.

reportActive / Technical Report | Accession Number: ADA105995 | Open PDF

Abstract:

Investigation of regional phase amplitudes at a large number of LRSM sites showed a pronounced increase of Pn, Pg, and Lg amplitudes at sedimentary structures relative to hard rock. In the early part of the coda and the main part of the wavetrain for Lg, lower order modes generated by mode conversion at local inhomogeneities must be present to explain the site variations and the coherence structure of Lg. A modification of Akis scattering theory is presented to explain such observations. Analysis of the late coda of Lg showed high crustal Q values at RKON and much lower values of OB2NV. At OB2NV the crustal Q appears to be frequency dependent, increasing from 200 to about 600 in the 1-10 Hz band. Author

Author(s):
Der, Zoltan A. ; O'donnell, Anne ; Klouda, Pamela J.
Author Organization(s):
TELEDYNE GEOTECH ALEXANDRIA VA SEISMIC DATA LAB
Descriptive Note:
Technical rept.,
Pagination:
0100

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release

RECORD

Collection: TR
Identifying Numbers
Report Number(s):
SDAC-TR-81-4, VSC-TR-81-11
Contract/Grant Number(s):
F08606-79-C-0007
Monitor Series:
TR-81-11
 Subject Terms
Joint Capability Areas:
JCA_5_Command and Control; JCA_5.3_Planning; JCA_1_Force Support; JCA_1.2_Force Preparation; JCA_1.2.5_Lessons Learned; JCA_6.3.3_Spectrum Management; JCA_1.3_Human Capital Management; JCA_1.2.3_Educating; JCA_1.3.2_Personnel Management; JCA_3.2_Engagement; JCA_3_Force Application; JCA_3.2.1_Kinetic Means; JCA_6.3_Net Management; JCA_6_Net Centric
Modernization Areas:
Fully Networked C3
Communities of Interest:
Sensors
Descriptor(s):
*SEISMIC DETECTION, *SEISMIC SIGNATURES, SIGNAL PROCESSING, SITES, REGIONS, FREQUENCY BANDS, WAVE PROPAGATION, MATHEMATICAL ANALYSIS, EARTH CRUST, SEISMIC WAVES, NUCLEAR EXPLOSION DETECTION, EARTHQUAKES, AMPLITUDE, TIME DOMAIN, GROUND STATIONS, SEDIMENTARY ROCK
Field(s)/Group(s):
Seismology, Seismic Detection and Detectors
Keyword(s):
LPN AFTAC VT 0709
Report Date:
1981 Mar 23