Interpretation of Aeromagnetic Data around Kafanchan Area, Northwestern Nigeria

Abstract

Aeromagnetic data of Kafanchan (Sheet 167) and Jema’a (Sheet 188), bound by latitudes 9 ̊ 00ʹ N and 10 ̊
00ʹ N, and longitude 8 ̊ 00ʹ E and 8 ̊ 30ʹ E, were combined and interpreted with the intention of delineating
and characterizing faults that exist within the area. Polynomial fitting technique was applied on the total magnetic intensity (TMI) field data in order to separate the residual anomaly from the regional field. The result indicated a NE-SW trend in deep seated structures. The result of the Second vertical derivative and analytic signal filters, applied on the residual magnetic anomaly, revealed the presence of several crisscrossing faults mostly trending in the NE-SW direction. Werner deconvolution technique was used to quantitatively estimate the depth to magnetic source. This revealed depth to source ranging from 100 m to 2,300 m. Suspected faults zones within the area have depths between 100 m and 500 m while areas with high magnetization are at depths between 500 to 1,000 m.