HR: 0800h
AN: S11B-0170    [Abstracts]
TI: A Broadband Seismological Investigation of the Cameroon Volcanic Line
AU: * Tibi, R
EM: tibi@seismo.wustl.edu
AF: Department of Earth and Planetary Sciences, Washington University, One Brookings Drive, St. Louis, MO 63130 United States
AU: Larson, A M
EM: alarson@geosc.psu.edu
AF: Department of Geosciences, Pennsylvania State University, 447 Deike Bld, University Park, PA 16802 United States
AU: Nyblade, A A
EM: andy@geosc.psu.edu
AF: Department of Geosciences, Pennsylvania State University, 447 Deike Bld, University Park, PA 16802 United States
AU: Shore, P J
EM: patrick@seismo.wustl.edu
AF: Department of Earth and Planetary Sciences, Washington University, One Brookings Drive, St. Louis, MO 63130 United States
AU: Wiens, D A
EM: doug@seismo.wustl.edu
AF: Department of Earth and Planetary Sciences, Washington University, One Brookings Drive, St. Louis, MO 63130 United States
AU: Nnange, J M
S11B-0170 AF: Institute for Geological and Mining Research, PO Box 4410 Nlongkak, Yaounde, N/A Cameroon
AU: Tabod, C
S11B-0170 AF: Department of physics, University of Yaounde I, PO Box 812, Yaounde, N/A Cameroon
AU: Bekoa, A
S11B-0170 AF: Institute of Geological and Mining Research, PO Box 370, Buea, N/A Cameroon
AB: Volcanic lines without any age progression cannot be explained by the conventional plume model, and their is no consensus about their origin. One family of models proposes that hot lines can be explained by added complexities in the plume framework. These propositions include lateral transport of plume material, recurrent volcanism due to relict plume material in the mantle along an old plume track, and multiple plumes. Other models include lithospheric tensional cracks or so called ``leaky frature'', and upwelling limb of small-scale convection cells. The Cameroon Volcanic Line (CVL), a 1500 km long line of Cenozoic volcanic constructs, is one of the most prominent volcanic lines lacking a discernable age progression. About one-half of the length of the CVL occurs on land, allowing extensive study without the expense of seafloor instrumentation. The PASSCAL Cameroon project is a 2-year passive-source broadband seismic experiment, consisting of an 8 station prototype deployment in 2005 and a 32 station deployment in 2006. Data recorded at the stations distributed throughout Cameroon will be used to examine the seismic structure of the crust and upper mantle beneath the CVL, and evaluate models for the origin of volcanic lines without age progression. Eight stations were installed in January 2005 and operated successfully throughout the year. Preliminary results of receiver-function analysis of the Moho, 410, and 660 km discontinuities for these stations will be presented.
DE: 7205 Continental crust (1219)
DE: 7208 Mantle (1212, 1213, 8124)
DE: 9305 Africa
SC: Seismology [S]
MN: Fall Meeting 2005