A Preliminary Study of the Chingshu, Geothermal Area, Ilala, Taiwan

Abstract

The Ch-ingshui geothermal area is located about 20 km southwest of Ilan, a city in northeastern Taiwan. This area was first selected by the Mining Research Service Organization, Industrial Technology Research Institute for reconnaissance survey of geothermal resources in 1973 by means of geological and geophysicalmethods. A total of fifteen shallow test wells, ranging from 161 m to 501 m, were also drilled, penetrating aquifers with rather high temperatures of up to 175OC. However, further exploration has been subsequently undertaken by the Chinese Petroleum Corporation from 1976 to explore for a usable geothermal resource with greater production for power generation. Up to now, over eight geothermal wells, CPC-CS-4TY 5T, 9T, 12T, 13T, 14T, 15T, and 16T, have been drilled to various depths, ranging from 1505 m to 3000 my having a roughly estimated thermal water flowrate of about 370 tons/hour under the flowing pressure of about 8 kg/cm Up to 9 on the gauge.

Before or during the drilling, several geological, geophysical, and geochemical methods have been conducted by CPC. A reliable geologic feature was realized by geological and gravity data, while a geothermal activity was revealed by microearthquakes, resistivity, temperature gradients, and concentrated mercury data.