Lying in the southern offshore of Xihu sag in East China Sea continental basin, Chunxiao condensate gas field is located in the continental shelf of East China Sea, 450 km south-east of Shenghai city and about 22km south of Tianwaitian gas-bearing structure.
In the area, oil and gas geophysical survey and reconnaissance begun in 1974. Chunxiao condensate gas field has been the largest gas field in East China Sea in terms of reserves so far, which was discovered on Feb.14,2000. The successfully drilled well Chunxioa-3 has high industrial gas flowing with a daily production of１４３.１９X104m3gas and ８８m3 oil. As of the end of 1998, it had proven 9.2 km2 gas-bearing area, OGIP 172.25×108m3 and a gas condensate OOIP 246.2×104 t. And a 30.3 km2 probable gas bearing area, a probable OGIP 590.27×108m3, 15.9 km2 possible gas-bearing area, 276.37×108m3 possible OGIP and 259.0×104 t possible gas condensate OOIP have been verified. Chunxiao condensate gas field is probably one of the largest gas fields in East China Sea basin.