Interpretation of Radiometric Anomalies over Some Parts of the Lower Benue Trough Nigeria, Using High Resolution Aero-radiometric Data (HRAR)

Abstract

The aero-radiometric data of these areas were employed to investigate the radioactive properties of rocks, with the aim of interpreting the concentrations of the principal radioactive elements (40K, 238U, 235U and 232Th) and possible hydrothermally altered zones that can host iron rich minerals. The radiometric data was subjected to enhancement techniques of producing concentration maps of Potassium, Thorium and Uranium. The total count map, ratio map of K/Th and the ternary image map were also produced to aid the interpretation process. The results from the Potassium, Thorium and Uranium maps displayed variations of high, moderate and low concentrations. The concentrations of these elements further mapped geology by distinguishing different rock types across the area. The total count map revealed the combined effects of the three radioactive elements, whereas the K/Thratio map revealed hydrothermally altered areas, reflecting at the NW-SW, NNE-SSW, SE, central portions and spots at the NE borders. Furthermore, the ternary image map revealed the combined intensities of the radioactive elements and possible hydrothermally altered environments, identified as (AE) on the image map.