Viscosity of oceanic asthenosphere inferred from remote triggering of earthquakes
A sequence of large interplate earthquakes from 1952 to 1965 along the Aleutian arc and Kurile-Kamchatka trench released accumulated stresses along nearly the entire northern portion of the Pacific Plate boundary. The postseismic stress evolution across the northern Pacific and Arctic basins, calculated from a viscoelastic coupling model with an asthenospheric viscosity of 5 x 10(17) pascal seconds, is consistent with triggering of oceanic intraplate earthquakes, temporal patterns in seismicity at remote plate boundaries, and space-based geodetic measurements of anomalous velocity over an area 7000 by 7000 kilometers square during the 30-year period after the sequence.
Pollitz
FF
F. F. Pollitz and R. Burgmann, Department of Geology, University of California, Davis, Davis, CA 95616, USA. B. Romanowicz, University of California Seismological Laboratory, 475 McCone Hall, Berkeley, CA 94720, USA.
Burgmann
R
Romanowicz
B