Report

Seismic Evidence for Olivine Phase Changes at the 410- and 660-Kilometer Discontinuities

See allHide authors and affiliations

Science  17 May 2002:
Vol. 296, Issue 5571, pp. 1300-1302
DOI: 10.1126/science.1069407

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Abstract

The view that the seismic discontinuities bounding the mantle transition zone at 410- and 660-kilometer depths are caused by isochemical phase transformations of the olivine structure is debated. Combining converted-wave measurements in East Asia and Australia with seismic velocities from regional tomography studies, we observe a correlation of the thickness of, and wavespeed variations within, the transition zone that is consistent with olivine structural transformations. Moreover, the seismologically inferred Clapeyron slopes are in agreement with the mineralogical Clapeyron slopes of the (Mg,Fe)2SiO4 spinel and postspinel transformations.

  • * To whom correspondence should be addressed. E-mail: sergei{at}quake.mit.edu

View Full Text