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Title: Differential shear-wave attenuation (deltat) across the East Pacific Rise

SS phases from earthquakes on fracture zones near the Easter Island Cordillera and the West Chile Rise which are recorded in the United States have reflection points on either side of the East Pacific Rise (EPR) near the equator. The east-west records from seven WWSSN stations of seven events in this region were used to obtain spectral amplitudes of horizontally polarized S and SS waves. SS-to-S amplitude ratios were formed, and differential attenuation (deltat) computed within the frequency band 0.01 to 0.11 Hz. The values of deltat vary between -0.1 sec and +35.8 sec for the 23 station-event paris used. However, the change in deltat with distance from the axis of the EPR does not reflect the smooth variation expected using a model of a simple cooling slab.
Authors:
Publication Date:
OSTI Identifier:
6024130
Resource Type:
Journal Article
Resource Relation:
Journal Name: Geophys. Res. Lett.; (United States); Journal Volume: 8:8
Research Org:
Department of Geoscience and Geophysical Research Center, RandDD New Mexico Institute of Mining and Technology, Socorro, NM 87801
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; OCEANIC CRUST; SEA-FLOOR SPREADING; SEISMIC S WAVES; ATTENUATION; SEISMIC SURFACE WAVES; EARTHQUAKES; GEOLOGIC STRUCTURES; PACIFIC OCEAN; PHASE VELOCITY; WAVE PROPAGATION; EARTH CRUST; SEAS; SEISMIC EVENTS; SEISMIC WAVES; SURFACE WATERS; VELOCITY 580201* -- Geophysics-- Seismology & Tectonics-- (1980-1989)