Recent surveys by Chinese and French geologists in Tibet's Yangbajain geothermal field have revealed three low resistivity layers in the shallow strata in the earth's crust which they presumed to be the three geothermal reservoirs.

The geologists conducted these surveys under the terms of a 1978 Sino-French scientific co-operation agreement. Their explorations were conducted over a 15-square-kilometre field,90 kilometres north of Lhasa ?the regional capital. The three low resistivity layers are: two kilometres, five to six kilometres and 14 to 18 kilometres below the surface.

Twenty-one exploratory boreholes and production wells have been drilled in Yangbajain since 1975. An experimental power station was constructed in 1977 with a generating capacity of 1,000 kilowatts. Recently a second station with a capacity of 3,000 kilowatts has also been put into operation.

China's first 110,000-volt high tension power line between Yangbajain and Lhasa generated by geothermal energy opened in December 1981. This 89kilometre-long line transverses a mountainous area at elevations exceeding 3,600 metres above sea level. Due to the rugged terrain, the 150 tons of material for the project had to be transported by people.

Tibet has the largest geothermal resources in the nation. Potential geothermal sites have been　discovered　in　66　of the autonomous region's 74 counties.

(This article appears on page 30, No. 10, 1982)