【摘要】 广安气田上三叠统须家河组须六段和须四段为低孔低渗储层,发育构造气藏、构造-岩性气藏和岩性气藏.气井产水普遍,气水分布复杂.根据地质、测井、测试和生产资料,研究了广安气田须六、须四段气水分布,探讨了控制气水分布的成因机理.垂向上,广安气田气水分异服从重力分异规律,纯气区多发育在构造顶部或相对的构造高部位,而富水区多发育在相对的构造低部位.空间上,气水分布受断层、储层物性、构造隆起幅度和地层倾角控制.储层物性越好,构造隆起幅度越高,地层倾角越大,则气水分异越彻底,而逆断层封堵气水运移,导致气水分布复杂化.不同的气水分异控制因素形成了不同类型的富水区,包括背斜翼部低部位型、鼻沟型、断层封闭型和成岩封闭型.更多还原

【Abstract】 The fourth and sixth members of Xujiahe Formation of upper Triassic in Guang’an gas field are low-porosity low-permeability sandstone reservoirs,and there are developed structural gas pools,structural-lithlogical gas pools and lithlogical gas pools. Almost all of the gas wells in this field produce water,which makes the water-gas distribution in the sandstone reservoirs very complicated. The water-gas distribution in the fourth and sixth members is investigated based on geological,logging,well testing and production data,and the control mechanism of the water-gas distribution is discussed. Vertically,the water-gas separation is controlled by gravity,which is reflected that the pure gas regions are often located in the top or relative high position of structures,while the water-rich areas are located in the relative low position of structures. In space,the water-gas distribution is controlled by fault,reservoir permeability,structural uplift amplitude and stratigraphic dip angle. High reservoir permeability,great structural uplift amplitude and large stratigraphic dip angle are helpful to the separation of water and gas,whereas inverse faults distributing in western part of the studied area often plug water and gas transportation and result in the complicated water-gas distribution relationship. Four major distribution modes of water-rich areas are formed under different water-gas distribution control factors,and accordingly water-rich areas locate in the lower part of anticline,dyke between structure noses,fault block and diagenetic block separately.更多还原