Basinal Structure Of Yola Arm Of The Upper Benue Trough Nigeria; Evidence From Aeromagnetic Data

Abstract

Aeromagnetic data interpretation of the Yola arm of the Upper Benue Trough has previously been carried out. However, no detail modeling of the Crustal Structures has been undertaken. Two composite reduced Aeromagnetic maps on a scale of 1:250,000 were digitized and processed using computer techniques. Analytical Signal, Power Spectrum and Upward Continuation methods were used prior to modeling of the subsurface structures. Forward and inverse modelings were done to determine the subsurface basin configuration. The result shows two sub-basins; the Lau and Yola sub-basins. The variations in sediment thickness within the Lau sub-basin is in the range of 2.0 – 4.5 km and in the Yola sub-basin 2.0 – 3.0 km respectively. The basin configurations from the modeled profiles depict that of horst and graben features resulting to variation in sediment thickness evident in Lau (Barwa to Yanga) subsector and Yola (Muleng) axis. The upward continuation revealed lineament trends in the NE-SW Yola (Muleng) axis and NW-SE Lau (Barwa to Yanga) subsector.

Keywords: Upper Benue Trough, Basin configuration upward continuation, Analytical signal, power spectrum.

Global Journal of Geological Sciences Vol. 6 (2) 2008: pp. 175-183