Mantle transition zone thickness beneath Cameroon: evidence for an upper mantle origin for the Cameroon Volcanic Line

被引：56

作者：

Reusch, Angela Marie ^{[1
]}

Nyblade, Andrew A. ^{[1
]}

Tibi, Rigobert ^{[2
]}

Wiens, Douglas A. ^{[2
]}

Shore, Patrick J. ^{[2
]}

Bekoa, Ateba ^{[3
]}

Tabod, Charles T. ^{[4
]}

Nnange, Joseph M. ^{[5
]}

机构：

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

[2] Washington Univ, Dept Earth & Planetary Sci, St Louis, MO 63130 USA

[3] Inst Geol & Min Res, Branch Geophys & Volcanol Res, Buea, Cameroon

[4] Univ Yaounde 1, Dept Phys, Yaounde, Cameroon

[5] Inst Geol & Min Res, Yaounde, Cameroon

来源：

GEOPHYSICAL JOURNAL INTERNATIONAL | 2011年 / 187卷 / 03期

基金：

美国国家科学基金会;

关键词：

Body waves; Dynamics of lithosphere and mantle; Hotspots; Africa; EDGE-DRIVEN CONVECTION; AFRICAN RIFT SYSTEM; RECEIVER FUNCTIONS; EAST-AFRICA; WEST-AFRICA; ATLANTIC; HOTSPOTS; TOPOGRAPHY; MAGMATISM; BASALT;

D O I：

10.1111/j.1365-246X.2011.05239.x

中图分类号：

P3 [地球物理学]; P59 [地球化学];

学科分类号：

0708 ; 070902 ;

摘要：

The thickness of the mantle transition zone beneath Cameroon has been mapped using data from the 2005-2007 Cameroon Broadband Seismic Experiment to evaluate models for the origin of the Cameroon Volcanic Line (CVL). Some 2200 receiver functions have been stacked using a 3-D velocity model, revealing P(s) conversions from the mantle transition zone discontinuities at depths of similar to 410 and 660 km. Results yield a nearly uniform transition zone thickness (251 +/- 10 km) that is similar to the global average, implying that any thermal anomalies in the upper mantle beneath the CVL do not extend as deep as the transition zone. This finding, when combined with regional P and S velocity models of the mantle, supports an explanation attributing the origin of the CVL to upper mantle processes such as an edge flow convection cell in the upper mantle along the northwestern side of the Congo Craton lithosphere.

引用

页码：1146 / 1150

页数：5

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