Qualitative evaluation of aeromagnetic data of Mmaku area, Nigeria, by means of upward continuation, band pass, highs pass and low pass filtering actions

The focus of this research is to delineate subsurface structures as well as their edges by interpreting a high resolution aeromagnetic data via qualitative approach. The study area lies between Latitude 6°00’- 6°30’N and Longitude 7°00’ - 7°30’E in Enugu state, south-east Nigeria. Regional-residual separation algorithm was applied on the total magnetic intensity aeromagnetic map in order to generate the residual and regional maps. On the resulting residual data, further enhancement techniques like the upward continuation at 5 km, 10 km and 20 km, band pass, high pass and low pass enhancement technique/filtering actions were undertaken. Result of the qualitative analysis shows that the study area is characterized by numerous faults and fractures expressed as NNE-SSW, E-W, N-S, NE-SW, NW-SE, and ENE-WSW tectonic trends. The NE-SW and NW-SE tectonic trends indicate that the area is affected by the charcot and oceanic fractures that existed within offshore Niger Delta, Nigeria while the ENE-WSW. NNE-SSW, E-W and N-S tectonic trends exemplify that the separation of Africa from South America affected the area.