摘要
Ⅰ. INTRODUCTION The Yaojie Coalfield is situated in Honggu District of Lanzhou, Gansu Province. It is a coal-bearing fault basin formed on the basis of the fossil upwarping of the Mid-Qilian Mountains in the Jurassic period. The Jurassic deposits accumulated directly on the metamorphic rock system of the Precambrian Huangyuan Group in which the Middle
基金
Project supported by the National Natural Science Foundation of China (Youth)and the Foundation of Laboratory of Biogeochemistry and Gasgeochemistry, Academis Sinica.
