Abstract: Tula basin is located among the southwestern Qaidam basin, the southeastern Tarim basin and the north of Kekexili mountain ranges, with above sea level of 3000 meters, being sparsely populated and very low mature exploration. Through field geologic survey and preliminary composite researches in petroleum geology, its formation mechanism has been confirmed, its structural units has been classified initially. The results show that the mudstone of Middle-Lower Jurassic in Tula basin is a major source rock; the favorable domains for petroleum prospecting are in the north and middle areas of the basin; particularly in Tula pasture sag,it is possible to find out oil and gas fields with both source and reservoir in Jurassic.

Key words: Tula basin, Qingzang plateau, Jurassic, source rock, exploration