Study of Thermal Water Resources in Sri Lanka Using Time Domain Electromagnetics (TDEM)

Abstract:

Thermal springs can be utilized as an environmental friendly source of renewable energy, as well as for other purposes. Time domain electromagnetic (TDEM) method is used as an accessory tool in geothermal exploration to investigate the local heterogeneities in geology. The study consists of two of the thermal springs in Sri Lanka, Wahawa and Mahaoya, both in the same crustal unit. Major structural discontinuities of the area vary between two peculiar fracture sets striking ENE and NW. Close relationships between these individual springs have been witnessed by their approximate major cation chemistries, which provoke the idea of geochemical provinces. Survey reveals the pathways of the heated water to the surface, at Wahawa, although the path is not clear at Mahaoya. Near surface resistivity diagrams can be used only to interpret the immediate depths of the springs. The expected structural relationships may be identified with a grid of TDEM soundings encompassing both the spring systems.

• Periodical: Advanced Materials Research (Volumes 955-959)
• Pages: 3198-3201
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.955-959.3198
• Online since: June 2014
• Authors: Nalaka Deepal Subasinghe*, Thusitha Bandara Nimalsiri, Nuwan Buddhika Suriyaarachchi, Bruce Hobbs, Morrel Fonseka, Chandra Dissanayake
• Keywords: Electromagnetics, Geothermal Water, Sri Lanka

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