Thickness Variations in the Lithospheric Mantle and the Low Velocity Zone of the Adamawa Plateau (Cameroon) from Teleseismic Receiver Functions
- 1 Department of Physics, Faculty of Science, University of Yaounde I, Yaounde, Cameroon
- 2 Department of Physics, Faculty of Science, The University of Bamenda, Bamenda, Cameroon
- 3 Department of Physics, HTTC Bambili, The University of Bamenda, Bamenda, Cameroon
- 4 Department of Physics, Faculty of Science, University of Yaounde I, Yaounde, Cameroon
- 5 Department of Physics, Faculty of Science, University of Yaounde I, Yaounde, Cameroon
Abstract
Teleseismic events recorded by stations located in the Adamawa Plateau have been treated using the inversion method of receiver functions. These six stations are part of a network of 32 large strip seismic stations installed in Cameroon between 2005 and 2007. This method allowed us to investigate the lithospheric mantle in that region. The results obtained from the velocity model have been compared to some existing results in this region. These results show the existence of a thick crust having an average thickness of about 35.2 km and a corresponding S wave velocity of 3.7 km/s. For an average S wave velocity of 4.4 km/s the lithospheric mantle appears to be thin in nature and has a thickness that varies from 39 km and 49.6 km. Beyond the lower lithospheric mantle, there exists a low velocity zone, whose thickness varies between 20 km and 43.9 km. The variation of the low velocity zone leads to variation of the lower boundary of the lithospheric mantle boundary at the depths ranging from 73.8 km and 85 km.
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