The Exploration of Malaysia’s Hot Springs for Geothermal Energy Development
Mohammad Noor Akmal ANUAR, Mohd Hariri ARIFIN, Hassan BAIOUMY and Hasiib Mansor
[The National University of Malaysia, Malaysia]
The non-volcanic hot springs’ existence in Peninsular Malaysia is hypothetically associated with a series of Triassic intrusion and the manifestation of granite batholiths. The differential age settings that range between 267 to 227 ± 2 Ma for Eastern Belt batholith and 219 to 198 ± 3 Ma for Main Range batholith have influence the hot springs’ surface temperature within the regions. In comparison, Eastern belt is I-type granite while Main Range is unique due to the transitional I-S-type granite. There are forty-five distributions of hot springs in Main Range granite with the surface temperature from 30˚C – 99˚C at the elongated Northwest and Southeast trends. On the contrary, Eastern Belt granite has a random distribution of eleven hot springs with 38˚C – 72˚C in surface temperature. Recently, there is a cardinal attempt in the harnessing of geothermal energy by using binary technology for small-scale electricity production in rural areas which shifts from geotourism and balneotheraphy purposes. The target area is known as Lojing in the western part of Kelantan with the surface temperature of 72 ˚C and geothermometry of 632 kJ/kg. A six-month progress of 300-meter drilling into the nearby granite fracture zone at the hot spring’s source has a promising prospect with the rate flow of 90 m3 /hours. The geophysical details of the conducted nearby-surface study within the area such as resistivity and induced polarisation provide the coordinates for drilling which yields a funnel-shaped borehole along the fracture zone. On the other hand, five sulphurous springs and mud pools from Miocene to Quaternary volcanic origins with the surface temperature of 55˚C - 77 ˚C are discovered in the southeast slope of Mount Maria in Tawau. The Sabah Orogeny of northwest subduction that faces Sulu arc has initiated andesitic to dacitic volcanism. The transcurrent and transpressional of Pliocene trending faults at the northwest have structurally established the Sabah hot springs’ existence. The Apas Kiri geothermal field investigation yields up to 14 km2 of land size with the reservoir temperature up to 200 ˚C which has the potential of 85 MWe resource capacity. Moreover, there are eight non-volcanic hot springs in Sarawak with the surface temperature of 38 ˚C – 43˚C along with a new discovery in Merarap, Lawas. There are three stages of concentric igneous intrusion in Kuching and other randomly disturbed areas in Sarawak that act as the main heat source for hot springs; (1) Triassic to late Tertiary granitoids, (2) Tertiary to Quaternary andesitic and basaltic lava as well as (3) Cretaceous to Quaternary dacitic and andesitic lava with pyroclastic. Jurassic to Cretaceous Bau Formation and Pedawan Formation have distinct host rocks for the hot springs at Panchor within the limestone and Paku black shales. Although more than sixty reported hot springs in Malaysia since 1960, there is an unclear gap of its sustainability issues and the nature of its reservoir. Hence, this study aims to investigate the sources of water-rock interaction for Malaysia’s hot springs in understanding its potentials and benefits for future geothermal prospects. Two different sources of hot spring have been identified which are volcanic and non-volcanic in origin. Furthermore, the quartz geothermometry study suggests that the reservoir temperature of Malaysia’s hot springs range from 93˚C - 196˚C. Based on the geochemistry of Peninsular Malaysia’s hot springs that indicate low sulphate concentration with Na-bicarbonate as its major minerals, it provides enough evidences for non-volcanic origin. Accordingly, the binary cycle system technology is suitable to develop a potential geothermal electric power plant in the future.
|        Topic: Exploration||Paper Number: 11190|