四川盆地普光大型气藏基本特征及成藏富集规律

Basic Characteristics and Concentration of the Puguang Gas Field in the Sichuan Basin

普光气田是在四川盆地近期发现的规模最大、埋藏最深、资源丰度最高的气田,2005年初向国家储委上交飞仙关组探明储量1144×108m3,普光气田已初步落实的三级储量超过3500×108m3。普光气田下三叠统飞仙关组储层岩性以单一的白云岩为主,发育鲕粒白云岩、残余鲕粒白云岩等储层;储层物性以中孔中渗、高孔高渗储层为主,为优质储层。深埋藏条件下的孔隙形成可能与深部热水溶蚀作用有关。临近主力生烃凹陷、优质储层发育、适时的古隆起可能是普光大型气田形成的有利条件。

The Puguang Field is the biggest and deepest gas field recently found in the Sichuan Basin of southern China with a proved gas reserve of 1144×10^8m^3 of the Feixianguan Formation reported to the National Mining Reserves Committee. Reserves of the three degree proved is 3500 ×10^8m^3, The reservoir rock of the Lower Triassic Feixianguan Formation is pure dolomite with oolitic dolomite and remnant oolitic dolomite. The reservoir has a high quality with medium to high porosity and permeability. The porosity may be related to the dissolution of deep thermal water. Closeness to the main hydrocarbon-producing sag, high-quality reservoir rock and timely uplifting are the favorable geological conditions to form this gas field.