Author(s)

S. A. Samaranayake^1,2*, Nalin De Silva³, U. Dahanayake⁴, H. O. Wijewardane⁴, N. D. Subasinghe²

¹National Ocean Affairs Committee, Ministry of Foreign Relations, Colombo, Sri Lanka.
²National Institue of Fundamental Studies, Kandy, Sri Lanka.
³Geological Survey and Mines Bureau, Pitakotte, Sri Lanka.
⁴Faculty of Applied Sciences, Rajarata University of Sri Lanka, Anuradhapura, Mihintale.

The Wahawa geothermal field which is located in the Eastern province of Sri Lanka has an average temperature of 60°C in its surface manifestations. Since the temperature is considerably high, it is important to explore the feasibility of direct utilization of the energy of this geothermal field. In the present study, electrical resistivity measurements were employed in a 20 km² region in order to delineate the Wahawa geothermal system and to understand the near-surface fracture pattern. Electrical resistivity mapping of the region has been carried out using Schlumberger array measurements with nominal current array spacing (half spacing) of 150 m and it was observed that there was a path of low (<30 W) apparent resistivity. These results revealed that the hotsprings resting on a hard rock terrain are presumably composed of metamorphic rocks, suggesting lateral movement of hotwater towards the hotsprings instead of a deep-influx. The area of surface manifestations is not suitable for utilization application due to clustering of the main feeding path. The major hotwater feeding path which is extending in the west direction can be recommended as a possible drilling target for direct utilization applications.

Electrical Resistivity, Fracture, Direct Utilization, Surface Manifestation

Samaranayake, S. , Silva, N. , Dahanayake, U. , Wijewardane, H. and Subasinghe, N. (2022) Delineation of Near Surface Water Flow Path of Wahawa Geothermal Field by Using 2D Inversion of Resistivity Data. Journal of Geoscience and Environment Protection, 10, 327-339. doi: 10.4236/gep.2022.108020.