A narrow, mid‐mantle plume below southern Africa
نویسندگان
چکیده
[1] New waveform tomographic evidence displays a narrow plume‐like feature emitting from the top of the large African low‐velocity structure in the lower mantle. A detailed SKS wavefield is assembled for a segment along the structure’s southern edge by combining multiple events recorded by a seismic array in the Kaapvaal region of southern Africa. With a new processing technique that emphases multi‐pathing, we locate a relatively jagged, sloping wall 1000 km high with low velocities near it’s basal edge. Forward modeling indicates that the plume’s diameter is less than 150 km and consistent with an iso‐ chemical, low‐viscosity plume conduit. Citation: Sun, D., D. Helmberger, and M. Gurnis (2010), A narrow, mid‐mantle plume below southern Africa, Geophys. Res. Lett., 37, L09302, doi:10.1029/2009GL042339.
منابع مشابه
Trace element and Sr-Nd-Pb isotope geochemistry of Rungwe Volcanic Province, Tanzania: implications for a Superplume source for East Africa Rift magmatism
*Correspondence: Paterno R. Castillo, Geosciences Research Division, Scripps Institution of Oceanography, University of California, San Diego, 8615 Kennel Way, La Jolla, CA 92037, USA e-mail: [email protected] †Present address: Sæmundur A. Halldórsson, Nordic Volcanological Center, Institute of Earth Sciences, University of Iceland, Reykjavik, Iceland The recently-discovered high, plume-like 3...
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