English

Abstract

Twelve sheets of aeromagnetic and aeroradiometric data covered the study area. The data was used to investigate heat sources. The aeromagnetic data were combined to form a composite map- total magnetic intensity (TMI) anomaly map and aeroradiometric data of each radio-element were combined to produce the radioelements maps. Regional-residual separation of the total magnetic intensity data was performed using polynomial fitting method on the aeromagnetic data. The filtered residual data was Fourier transformed after dividing the whole area into thirty-five overlapping sections for spectral analysis, to determine Curie point depth, geothermal heat flow and magnetic trends. Calculation of ratios was used for the radio-elements to estimate the radioactive heat values in the study area, and the surface geology of the study area was delineated to outline each rock unit to match their density and corresponding radio-elements. The results of the analysis of aeromagnetic data showed that the shallow magnetic source ranges from 0.59 to 3.86 km, deeper source ranges from 8.03 to 19.85 km, Curie point depth values ranges from 14.64 to 38.62 km and geothermal heat flow values ranges between 37.54 and 99.02 mWm-2. The results of the analysis of the radioactive heat production of the study area range between 0.01 and 5.43 μWm-3. The highest heat produced was from the Shale with radioactive heat production as high as 5.43 μWm-3. There are high geothermal heat flow and radioactive heat values in Aimeke and Ogobia.   Key words: Aeromagnetic, aero-radiometric, radioactive, geothermal.