Interpretation of High Resolution Aeromagnetic Data to Estimate the Curie Point Depth Isotherm of Parts of Middle Benue Trough, North-East, Nigeria

Abstract

This research work deals with estimation of Curie point depth isotherm using aeromagnetic data of part of middle Benue Trough, North-East, Nigeria. The study area lies within the Longitude 9ºE – 10ºE and Latitude 8ºN – 9.50ºN with an estimated total area of 18150km2. Regional/Residual separation was performed on the total magnetic intensity using polynomial fitting. The residual map was divided into fourteen spectral blocks and the log of spectral energies were plotted against frequency. Centroid depth and depth to top boundary obtained were used to estimate the Curie point depth isotherm which is the depth at which the crust and uppermost mantle magnetic materials cease to be magnetic as a result of increase in temperature as depth increases. The result shows that the Curie isotherm depth varies between 17.04km to 27.40 km with an average value of 22.5 km. Based on previous research works, the Curie point depth isotherm obtained from this study is a good source of geothermal potential.