Phase velocities of rayleigh waves in the MELT experiment on the east pacific rise.

作者信息

Forsyth DW, Webb SC, Dorman LM, Shen Y

机构信息

D. W. Forsyth, Department of Geological Sciences, Brown University, Providence, RI 02912, USA. S. C. Webb and L. M. Dorman, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA. Y. Shen, Woods Hole Ocea.

出版信息

Science. 1998 May 22;280(5367):1235-8. doi: 10.1126/science.280.5367.1235.

DOI:10.1126/science.280.5367.1235

PMID:9596571

Abstract

The phase velocities of Rayleigh waves increase more rapidly with distance from the East Pacific Rise (EPR) axis than is predicted by models of conductive cooling of the lithosphere. Low velocities near the axis are probably caused by partial melt at depths of 20 to 70 kilometers in a zone several hundred kilometers wide. The lowest velocities are offset to the west of the EPR. Wave propagation is anisotropic; the fast direction is approximately perpendicular to the ridge, parallel to the spreading direction. Anisotropy increases from a minimum near the axis to 3 percent or more on the flanks.

摘要