异常高压气藏岩石变形特征及其对开发的影响――以克拉2气田为例

克拉 2气田是至今为止在中国陆上找到的最大整装干气气藏 ,也是“西气东输”的主力产气场 ,因此 ,开发好克拉 2气田意义重大而深远。由于该气田地层压力高 (74.3 6 MPa) ,压力系数高达2以上 ,属于异常高压气藏 ,故在衰竭式开采过程中 ,随着气藏的压力下降 ,该气藏的岩石骨架要承受比常规气藏大得多的净上覆压力 ,结果会使岩石发生显著的弹塑性形变和岩石渗透率、孔隙度和岩石压缩系数等物性参数减小 ,从而影响气藏的开发效果 1。据此 ,研究气藏开发过程中岩石形变对产能的影响是一个非常重要的课题。依据岩石覆压实验研究了克拉 2气田异常高压气藏岩石变形特征及其对开发的影响

CHARACTERISTICS OF THE ROCK DEFORMATION IN ABNORMAL HIGH-PRESSURE GAS RESERVIOR AND THE STUDIES OF ITS INFLUENCE ON GAS RESERVIOR EXPLOITATION:EXAMPLE FROM THE KELA 2 GAS FIELD

Kela 2 gas field is the biggest land monoblock dry gas reservoir which has been discovered in China so far It is essential to make it a high productivity gas field as it is the main production area of "West\|East Natural Gas Transportation" Project Kela 2 gas field is an overpressure reservoir The formation pressure of this gas field is very high (74 36 MPa) And its pressure parameter is as high as 2 or more During the natural depletion, the overpressure formation rock will stand the net weight above as reservoir pressure is getting lower and lower And great plastic deformation would occur in the formation rock Such characteristics as permeability, porosity and compressibility factor will decrease And it would negatively affect gas production And so, during the development of Kela 2 gas field, rock deformation is a watchful problem for production capacities This paper is to research the overpressure rock deformation characteristics of Kela 2 gas field and its effects on gas production according to rock coverage experiment