By Conrad Richter

TORONTO, Feb 5 -- China expects to find "ample oil reserves" in the Changtang region of northern Tibet. According to Zhao Huan, chief engineer with the Geophysical Bureau of the China National Petroleum and Natural Gas Corporation, existing data suggests that the Changtang Basin will yield "abundant reserves of oil and natural gas." His comments were published in an article in a recent issue of China's Tibet, a government propaganda magazine.

Tibet was a vast ocean 200 million years ago, an area referred to by geologists as the Ancient Mediterranean Sea. With the rise of the Himalaya 30 million years ago, the ocean receded to give way to the Changtang Basin, 4,500 metres above sea level.

Two sedimentary layers beneath the basin offer "high prospects for the discovery of oil and gas reserves": an upper level representing deposits 70 million years old and a lower level representing deposits 135 million years old. Two regions, the Tuboco Lake - Paitan Lake area and the Tumain area are identified as the most likely to contain oil and gas. No estimates of reserves were mentioned.

According to the article, oil and gas exploration began in the 1970s but only gained momentum when Zhao and a group of geologists were sent to Tibet in 1995. A prospecting team of 2,000 was sent in April of 1996 when the likelihood of significant finds became evident. The team is exploring in a 400,000 square kilometre area.