Integrated Study of Central Nigeria Geology and Tremor Activities Using Air Borne Radiometric Data

Abstract

To determine the true causes of earth tremors, high resolution maps created from aircraft radiometric datasets were utilized to illustrate the primary lithology and structural features found in the north-central Nigeria. A range of magnetic amplitudes was seen from the Total Magnetic Intensity. This implies that the underlying rocks are at various depths and have variable magnetic mineral contents depending on the type of rock unit. This is confirmed by generated concentration maps of percentage Uranium, Thorium (u/th)Uranium Potassium (u/k) and Thorium Potassium (th/k) these maps showed low to moderate and high concentration of radio-element. Thorium (0 < 6.4ppm to > 31.9ppm), potassium (0% to > 4.1%), uranium (1.14ppm to < 0.76ppm%). respectively in rocks covering the study area. These results revealed that the study area is geologically characterized by granite gneiss, porphyritic granite rock, felsic granitic rock, schist and migmatite gneiss. Thus, these observed changes in the Total Magnetic Intensity (TMI) map with a low to moderate concentration of the radio elements-identified suggest weathering and intense metamorphism, which could be regarded as unstable, allowing for transmission of seismic energy leading to tremor activities in the study area.