Pn wave velocities beneath the Tanzania Craton and adjacent rifted mobile belts, East Africa

被引：23

作者：

Brazier, RA ^{[1
]}

Nyblade, AA

Langston, CA

Owens, TJ

机构：

[1] Penn State Univ, Dept Geosci, University Pk, PA 16802 USA

[2] Univ S Carolina, Dept Geol Sci, Columbia, SC 29208 USA

来源：

GEOPHYSICAL RESEARCH LETTERS | 2000年 / 27卷 / 16期

关键词：

D O I：

10.1029/2000GL011586

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

P wave travel times from regional earthquakes recorded by the Tanzania Broadband Seismic Experiment have been inverted for long wavelength (>100 km) Pn velocity variations beneath Tanzania using a generalized inverse algorithm. Pn velocities, on average, are 8.40 to 8.45 km/s beneath the center of the Tanzania Craton, 8.30-8.35 km/s beneath the terminus of the Eastern Branch of the rift system, and 8.35-8.40 km/s beneath the Western Branch. These velocities indicate that there are no broad (>100 km wide) thermal anomalies in the uppermost mantle beneath areas of rifting in Tanzania, and suggest that thermal anomalies present deeper in the mantle have not yet reached the base of the crust.

引用

页码：2365 / 2368

页数：4

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