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

作者：Reusch Angela Marie^*; Nyblade Andrew A; Tibi Rigobert; Wiens Douglas A; Shore Patrick J; Bekoa Ateba; Tabod Charles T; Nnange Joseph M

来源：Geophysical Journal International, 2011, 187(3): 1146-1150.

DOI：10.1111/j.1365-246X.2011.05239.x

• Body waves
• Dynamics of lithosphere and mantle
• Hotspots
• Africa

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.

• 出版日期2011-12