Determination of Curie Depth Isotherm and Geothermal Studies over Parts of Nasarawa and Environs, North Central Nigeria
The high resolution aeromagnetic data was analyzed to estimate depths to the bottom of magnetic sources as proxy information about the thermal conditions within the crust in Nasarawa area. This area is particularly important for geothermal exploration because of its high heat flow and geothermal gradients. The result of this investigation revealed that Curie point depth vary between 18km and 23km with deeper Isotherm at the northwestern part and shallow Isotherm at the south eastern part, this means that the Curie Isotherm surface around Awe Dorowa and Akiri may likely coincide with the Moho, these variations of curie depth isotherm could be related to the different tectonic activities, which involve astenospheric updoming, crustal thinning and stretching, emplacement of igneous bodies and block faulting in the Benue Trough. The calculated heat flow varies between 63 mWm-2- 80 mWm-2 and geothermal gradient varies between 25°C/km- 32°C/km. The south eastern part is characterized by high heat flow (80mW/m2), and shallow Curie depth (18 km), due to the geothermic nature of the area, the heat due to magmatic activities as well as heat from thinning of the crust is responsible for raising the temperature in these areas. The north western portion of the studied area has lower heat flow (63mW/m2) and deeper Curie depth (23 km) due to Isostacy. Variations in the Curie Depth compare reasonably well with the heat flow and with the Geothermal Gradient, this study also revealed that the south eastern part of the study area has potentials for geothermal energy.
Rowland Akuzigi Ayuba,
Determination of Curie Depth Isotherm and Geothermal Studies over Parts of Nasarawa and Environs, North Central Nigeria, International Journal of Energy and Environmental Science.
Vol. 3, No. 4,
2018, pp. 69-81.
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