Seismic anisotropy in eastern Africa, mantle flow, and the African superplume

被引：71

作者：

Bagley, Brian ^{[1
,2
]}

Nyblade, Andrew A. ^{[1
]}

机构：

[1] Penn State Univ Univ Pk, Dept Geosci, University Pk, PA USA

[2] Univ Minnesota, Dept Earth Sci, Minneapolis, MN 55455 USA

来源：

GEOPHYSICAL RESEARCH LETTERS | 2013年 / 40卷 / 08期

基金：

美国国家科学基金会;

关键词：

anisotropy; shear wave splitting; african superplume; VELOCITY STRUCTURE BENEATH; SAUDI-ARABIA; SHEAR; EVOLUTION; DEFORMATION; LITHOSPHERE; TOMOGRAPHY; PATTERNS; ETHIOPIA; PLATEAU;

D O I：

10.1002/grl.50315

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

New estimates of seismic anisotropy from shear wave splitting measurements in eastern Africa reveal a pattern of seismic anisotropy dominated by a NE alignment of fast polarization directions with local changes around the thick Archean lithosphere of the Tanzania craton. The overall pattern is consistent with mantle flow from the African superplume but not with absolute plate motion, a plume head, or fossil anisotropy in the lithosphere. In combination with tomographic images of the African superplume, this finding suggests that plateau uplift, volcanism, and continental breakup along the Afro-Arabian rift system is strongly influenced by flow from the lower mantle and indicates a connection between lower mantle processes and the tectonic deformation of the Earth's surface.

引用

页码：1500 / 1505

页数：6

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