塔中碳酸盐岩凝析气藏储集空间类型判别及开发对策

塔中地区奥陶系碳酸盐岩由于构造作用和岩溶作用等复杂的地质作用而缝洞发育,形成种类多样的储集空间,如何提高塔中地区奥陶系碳酸盐岩不同储集空间类型凝析气藏采收率是目前塔中凝析气藏高效开发面临的主要难题。综合钻井、录井、测井静态资料和完井酸压改造、试井、试采动态等资料制定了一套碳酸盐岩储层储集类型综合判别技术及标准。借助室内实验和现场试验相结合的方法,论证了不同储集空间类型的凝析气藏提高采收率对策。研究表明,对于洞穴型储层适宜注水替气开采,对于裂缝孔洞型或孔洞型凝析气藏采用早期注气保压的开发方式。提出的碳酸盐岩凝析气藏储集空间类型判别方法及其对应的开发对策,有效地指导了碳酸盐岩凝析气藏高效开发。

Decision Methods of Diffident Types of Pore Space of Tazhong Carbonate Condensate Gas Reservoirs and Exploitation Strategies

Ordovician carbonate rocks in the Tazhong area form a variety of reservoir spaces due to the complex geologic processes such as tectonism and karstification. How to improve the recovery efficiency of condensate gas reservoirs with various reservoir spaces of Ordovician carbonate rocks in Tazhong area is the main problem in the development of these condensate gas reservoirs. A set of technology and standards of comprehensive identifying the reservoir types of carbonate rock reservoirs is formulated through combining the static data of drilling, logging, and well logging with the dynamic data of acid fracturing while completion, well testing, production test and other information. By means of the combination of laboratory experiment and field testing, the strategy of enhancing recovery factor of condensate gas reservoirs with various types of reservoir space is proved. The study shows that the cave type reservoir is suitable for water injection for gas recovery, while the development of early gas injection and pressure keeping is suitable for the fissure-&-hole type or pore type condensate gas reservoirs. The method of identifying the reservoir types of carbonate rock condensate gas reservoirs and its corresponding development policy proposed in the paper effectively guide the efficient development of carbonate condensate gas reservoirs.