Moho Discontinuity Depth Estimates for the Cameroon Volcanic Line from Gravity Data

Abstract

In this work, the Moho depth in a part of the Cameroon Volcanic Line (CVL) between the latitudes 3°30´ to 6°33´N and the longitudes 8°50’ to 11°27’E, has been estimated covering two distinct regions: the Mount Cameroon and the Bamenda by the use of polynomial separation of gravity data and spectral analysis along two profiles. The Moho is uplifted in the Mount Cameroon region, where the crust is thinned to about 24 km. In the Bamenda region, the crustal thickness is found to be normal at about 31 km. The high positive gravity anomalies of up to 100 m Gal observed in this area indicate the thinning of the crust in the Mount Cameroon region. Seismic and gravity data indicate a crustal thickness of 30-34 km along the continental parts of the Cameroon Volcanic Line, except in the Adamawa plateau, where the crust’s thickness ranges between 20-23 km. The crustal thickness of about 31 km in the Bamenda region is an evidence of perfect isostatic compensation, which suggests a deep seated source for the negative anomaly, resulting in a general asthenospheric uplift along the Cameroon Volcanic Line.