TECTONIC FEATURES AND HYDROCARBON POTENTIAL OF THE EASTERN QAIDAM BASIN

Qaidam Basin, situated in the northeastern Qinghai\|Tibet plateau of western China at 35°55′～39°10′N and 90°～98°20′E, is surrounded by thrusts or folded belts. It is adjacent to the Qilian Mountains on the north and northeast and to the Kunlun Mountains on the south, and to the Altun Mountains on the northwest. Qaidam plate is attributed to carbonate platform and non\|marine basin. The first stage is plate\|form from Sinian to Triassic, and the second is basin\|form in intraplate during non\|marine depositional period in Mesozoic and Cenozoic. 1 Tectonic feature The main structural elements of the eastern Qaidam basin, which the west border line is Germ and Dunhuang highway, include the Huobuxun depression, the Tin\|Iron Mountains ridge and Delingha depression as the secondary tectonic unit. These depressions extend along the northeastern edge of the Qinghai\|Tibet plateau, and form above a zone of Paleozoic pericraton subsidence at the north edge of the Qaidam plate during intracontinental orogenic phase in the Indosinian.