The Junggar Basin is an important oil‐ and gas‐bearing basin, with thick source rocks, of Carboniferous. Permian. Triassic and Jurassic ages. Hydrocarbon accumulations are controlled by major faults which trend NNW. NW and NE; NE‐striking reverse faults constitute the Kelemay thrust‐zone in the NW basin margin; those trending NW are of lesser importance; and those trending NNW on the southern basin margin control the formation of en echelon anticlines (Kuang, 1989), which are important sites of hydrocarbon accumu