川中充西须四段致密砂岩气田气水分布特征及成因

Gas-water distribution and genesis of the tight sandstone gas field in Member 4 of Xujiahe Formation in Chongxi of Central Sichuan,China

探讨川中地区充西构造须四段气水分布特征及其控制因素。对须四段致密砂岩地层水物理化学特征进行研究,利用综合测井解释、试油成果开展了单井储层及气水层识别。井间气水层对比研究成果表明须四段致密气层的气水过渡带较宽,没有明显的气水界面,仅存在含水饱和度向上逐渐降低的趋势。气水分布受储集层物性、断层和裂缝系统、褶皱等多种因素控制,充西须四段致密砂岩气田气水分布模式可归纳为断层侧翼控制型、断层末端效应控制型、岩性-褶皱控制型、褶皱控制型。

This paper researches the gas-water pattern and controlling factor of Member 4 of Xujiahe Formation（T3x^4） in the Chongxi structure of Central Sichuan.By researching the physical and chemical characteristics of the formation water of T3x^4,utilizing the synthetic well logging interpretation and the well testing outcome,the authors identify the reservoir of single well and the gas or water layer in the reservoirs.The research results of comparing the gas and water layers between wells indicate that the gas-water transition zone of T3x^4 tight gas reservoir is wide,there is no obvious gas-water interface,and only the water saturation gradually decreases up from bottom to top.The gas-water distribution is controlled by a variety of factors,such as reservoir physical properties,faults and fractures system,fold,etc..The gas-water distribution patterns of T3x^4 tight sandstone gas field of Chongxi include the fault flanking controlling type,fault terminal effect controlling type,lithology-fold controlling type and fold controlling type.