Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 22 May 1998:
Vol. 280. no. 5367, pp. 1235 - 1238
DOI: 10.1126/science.280.5367.1235
Prev | Table of Contents | Next

Reports

Phase Velocities of Rayleigh Waves in the MELT Experiment on the East Pacific Rise

Donald W. Forsyth, * Spahr C. Webb, LeRoy M. Dorman, Yang Shen

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.

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 Oceanographic Institution, Woods Hole, MA 02543, USA.
*   To whom correspondence should be addressed at donald_forsyth{at}brown.edu

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Water follows carbon: CO2 incites deep silicate melting and dehydration beneath mid-ocean ridges.
R. Dasgupta, M. M. Hirschmann, and N. D. Smith (2007)
Geology 35, 135-138
   Abstract »    Full Text »    PDF »
The Hawaiian SWELL pilot experiment--Evidence for lithosphere rejuvenation from ocean bottom surface wave data.
G. Laske, J. P. Morgan, and J. A. Orcutt (2007)
Geological Society of America Special Papers 430, 209-233
   Abstract »    Full Text »    PDF »
Field Test of an Inexpensive, Small Broadband Ocean-Bottom Seismograph.
(2003)
Bulletin of the Seismological Society of America 93, 152-171
Evidence for shallow isostatic compensation of the southern Rocky Mountains from Rayleigh wave tomography.
A. Li, D. W. Forsyth, and K. M. Fischer (2002)
Geology 30, 683-686
   Abstract »    Full Text »    PDF »
Seismic Anisotropy and Global Geodynamics.
J.-P. Montagner and L. Guillot (2002)
Reviews in Mineralogy and Geochemistry 51, 353-385
   Full Text »    PDF »
A Complex Pattern of Mantle Flow in the Lau Backarc.
G. P. Smith, D. A. Wiens, K. M. Fischer, L. M. Dorman, S. C. Webb, and J. A. Hildebrand (2001)
Science 292, 713-716
   Abstract »    Full Text »
A Broadband Ocean-Bottom Seismometer System Based on a 1-Hz Natural Period Geophone.
(2001)
Bulletin of the Seismological Society of America 91, 304-312
Shipboard Geophysical Indications of Asymmetry and Melt Production Beneath the East Pacific Rise Near the MELT Experiment.
D. S. Scheirer, D. W. Forsyth, M. Cormier, and K. C. Macdonald (1998)
Science 280, 1221-1224
   Abstract »    Full Text »
Structure of the Upper Mantle Under the EPR from Waveform Inversion of Regional Events.
S. C. Webb and D. W. Forsyth (1998)
Science 280, 1227-1229
   Abstract »    Full Text »
Shear-Wave Splitting and Implications for Mantle Flow Beneath the MELT Region of the East Pacific Rise.
C. J. Wolfe and S. C. Solomon (1998)
Science 280, 1230-1232
   Abstract »    Full Text »
Mantle Discontinuity Structure Beneath the Southern East Pacific Rise from P-to-S Converted Phases.
Y. Shen, A. F. Sheehan, K. G. Dueker, C. de Groot-Hedlin, and H. Gilbert (1998)
Science 280, 1232-1235
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)