碳酸盐岩缝洞型油藏缝洞连通体识别及刻画研究

Identification and characterization of fracture-connecting components in carbonate fractured-vuggy reservoirs

李小波 李新华 荣元帅 何新明 巫波

Li Xiaobo Li Xinhua Rong Yuanshuai He Xinming Wu Bo

中国石化 西北油田分公司 勘探开发研究院, 乌鲁木齐 830011

Research Institute of Exploration and Productions, SINOPEC Northwest Company, Urumqi, Xinjiang 830011, China

塔河油田碳酸盐岩缝洞型油藏具有极其复杂的缝洞空间结构,识别和刻画储层内的缝洞连通体一直是油藏描述的技术难题,目前尚缺乏较有效的处理方法.基于现代岩溶发育模式,选取溶洞体和微断裂-裂缝体系进行地震属性特征识别;运用岩溶地震相分析方法对溶洞和裂缝进行多属性融合的地震相分析,再采用三维地质网格定量化并形成几何格架地质模型,实现对缝洞连通体的刻画.结果表明:振幅梯度属性可有效识别"串珠状"强反射与地层反射的边界,从而检测和成像出"串珠状"反射的溶洞体的空间分布;最大曲率属性能有效地描述断裂和裂缝在平面上的线型特征和几何边界特征,从而反映裂缝通道展布.岩溶地震相分析刻画的缝洞连通体呈现了缝洞储层的几何形态和空间的延展趋势,实现了对缝洞体内部结构和连通通道的精细描述.通过预测和表征缝洞连通体的分布位置和形态特征,为缝洞型油藏储集空间的精细描述提供重要技术支撑.

The spatial structure of fractures in the carbonate fractured-vuggy reservoirs in the Tahe Oilfield was very complicated; hence the identification and characterization of fracture-connecting components were difficult. Based on modern karst mode, we selected isolated caves, karst rivers and micro-fractures to identify seismic properties. Seismic facies analysis was used to study caves and fractures. 3D geologic network was applied to establish a geometric geologic model quantitatively, which could describe the fracture-connecting components. Amplitude gradient properties could effectively determine the boundaries between "beaded" strong reflectance and formation reflectance, which could detect and image the spatial distribution of caves with beaded reflectance. Maximum curvature attributes could effectively describe the plane linear features and geometric boundary characteristics of faults and fractures, which showed the distribution of fractures. The fracture-connecting components described by karst seismic facies described the geometric states and spatial extensions of fractured-vuggy reservoirs; hence realized the precise description of internal structure and communicating channel, and provided important technical supports or the development of fractured reservoirs.

国家科技重大专项"塔里木盆地大型碳酸盐岩油气田开发示范工程"(2011ZX05049)资助.

https://doi.org/10.11781/sysydz2014S1044