Nanbaxian gas field is located in Mahai-Nanbaxian anticlinal zone of Dahonggou uplift in the faulted block zone of the northern Tarim basin within Xizhou’s Dacaidan town, Qinghai province.
Oil and gas exploration initialed in the late 50’s last century in the area. The commercial hydrocabon flow found in well Xian-3 in 1995 verified the existence of Nanbaxian condensate gas reservoir. As of the end of 1998, it had proven a probable OOIP of 775.3×104t and recoverable reserve 223.9×104t ；OGIP of solution gas 12.81×108m3 and recoverable reserve 7.11×108m in an overlapping oil bearing area of 13.6 km2 ；a probable OGIP of 124.39×108m3 and recoverable reserve of 69.20×108m3 in an overlapping gas-bearing area of 9.1 km2 and gas condensate OOIP of 7.8×104t and recoverable reserve of 2.1×104t. In the whole area, the overlapping gas bearing area is 15.1 km2 . Nanbaxian condensate gas field is a medium-deep gas field with high abundance.