Magnetotelluric Case Study from Ain Al-Harrah Hot Spring, Al-Lith, Saudi Arabia

A couple of studies show that Saudi Arabia has promising geothermal resources. The most prominent sites are located around Al-Lith, with four hot springs, where Ain Al-Harrah has the highest temperature. Previous studies suggest that this hot spring's geothermal reservoir is promising and may provide the Al-Lith region with long-term electricity. Our key objective is to investigate and explore more comprehensively the prospect of geothermal resources around the Ain Al-Harrah hot spring. To achieve this goal, we acquired broadband magnetotellurics (MT) data in the period range 0.001-60 s for three different sampling frequencies at 15 soundings along one profile. The 2D inversion results show three main units. A conductive anomaly (< 30 Omega.m) at a depth > 3.5 km below the surface is most likely related to a geothermal heat source. The high resistive zones (roughly 200-4000 Omega.m) are associated with hard-rock geological formations. Although uncertain, a detected medium resistive body (30-200 Omega.m) at a depth of 800 m below the surface possibly indicates the pathway of geothermal fluids forming a convection cell between the hot body and the surface. A lateral resistivity discontinuity is considered a fracture zone acting as a pathway for the fluids to reach the surface forming the hot spring.

Automated summary

Several studies suggest that Saudi Arabia has promising geothermal resources, with the most notable location being the Ain Al-Harrah hot spring near Al-Lith. By investigating the potential of geothermal resources in this area, it was found that there is a conductive anomaly related to a geothermal heat source, high resistive zones associated with hard-rock geological formations, and a medium resistive body possibly indicating a pathway for geothermal fluids.