Curie point depth and geothermal heat flow analysis of the northwest Ethiopian plateau

Abstract

The northwest Ethiopian plateau (NWEP) has thick flood basalts from the Eocene–Miocene Trap provinces. While previous studies have established the Ethiopian Rift Valley as a region of significant geothermal potential, the NWEP has remained largely unexplored in this regard. This study aims to estimate the Curie point depth, heat flow, and geothermal gradient in the NWEP, through spectral analysis of magnetic data in the NWEP, covering the region between 9.8 and 14.1°N latitude and 36–39.64°E longitude. The magnetic anomaly map was processed using Reduction to the Pole (RTP) filter to generate the RTP corrected magnetic map of the study area. This map was subsequently partitioned into twenty four overlapping blocks, of which each one was analyzed by means of spectral methods. The estimated Curie point depths range from 14 to 75 km, while the geothermal gradient varies between 8 and 38 °C/km, with corresponding heat flow values ranging from 19 to 94 mW/m². The localities of Metema, Kora, Amanuel, Wukro, Wanzaye, Tsi Abay, Arb Gebeya, Dogolo, Alem Ketema, and Anchekorer exhibit Curie point depths (CPD) of less than 20 km. These regions exhibit high heat flow, elevated geothermal gradient, and shallow CPD, all of which indicate substantial geothermal potential. The findings contribute to a better understanding of the crustal thermal structure of the NWEP.