Differential shear‐wave attenuation (δt*) across the East Pacific Rise
1981; American Geophysical Union; Volume: 8; Issue: 8 Linguagem: Inglês
10.1029/gl008i008p00861
ISSN1944-8007
Autores Tópico(s)High-pressure geophysics and materials
ResumoSS 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 (δt*) computed within the frequency band 0.01 to 0.11 Hz. The values of δt* vary between −0.1 sec and +35.8 sec for the 23 station‐event pairs used. However, the change in δt* with distance from the axis of the EPR does not reflect the smooth variation expected using a model of a simple cooling slab.
Referência(s)