Exploration of Shallow Geothermal Energy Aquifers by Using Electrical Resistivity Survey in Laki Range Jamshoro district Sindh, Pakistan

Abstract

Geothermal water is increasingly used around the world for its exploitation. Bulk electrical resistivity differences can bring significant information on variation of subsurface geothermal aquifer characteristics. The electrical resistivity survey was carried out in Laki range in lower Indus basin in the study area to explore the subsurface geothermal aquifers. The Schlumberger electrode configuration with range from 2 m to 220 m depth was applied. Three prominent locations of hot springs were selected including Laki Shah Saddar, Lalbagh and Kai hot spring near Sehwan city. After processing resistivity image data, two hot water geothermal aquifers were delineated at Laki Shah Sadder hot springs. The depth of first aquifer was 56 m and its thickness 38 m in the limestones. The depth of second aquifer of 190 m and with thickness of 96 m hosted in limestone. In Lalbagh hot springs two geothermal aquifers were delineated on the basis of apparent resistivity contrast, the depth of first aquifer zone in sandstone was in sandstone 15 m and thickness 12 m, while the depth of second aquifer was 61m and thickness was 35m. In Kai hot springs two hot water geothermal aquifers were delineated. The depth of first geothermal aquifer was 21m and thickness was 18 m and the depth of second aquifer was 105 m and thickness was 61m present in sandstone lithology. Present work demonstrates the capability of electrical resistivity images to study the potential of geothermal energy in shallow aquifers. These outcomes could potentially lead to a number of practical applications, such as the monitoring or the design of shallow geothermal systems.