蟠龙油田长2储层裂缝分布及油气地质意义

Fracture distribution and geological significance of Chang 2 reservoir in Panlong Oilfield

白玉彬¹ 赵靖舟¹ 陈孝平² 章爱成²

西安石油大学油气资源学院，陕西 西安 710065 延长油田股份有限公司蟠龙采油厂，陕西 延安 717208

School of Petroleum Resources, Xi′an Petroleum University, Xi′an 710065, China Panlong Oil Production Plant, Yanchang Petroleum Co. Ltd., Yan′an 717208, China

岩心观察、薄片资料、常规物性分析等研究表明，鄂尔多斯盆地蟠龙油田长2储层天然裂缝发育，且主要为高角度裂缝，裂缝充填物主要为方解石，部分未充填裂缝含油性好。采用渗透率异常频率分析方法，研究长2储层裂缝平面变化规律，产量高的井主要落于渗透率异常值在5%~30%和大于50%两个区间内。宏观裂缝的大量存在，起到沟通长7有效烃源岩与长2储层的桥梁作用，从而形成长2储层丰富的石油聚集。微裂缝对基质孔隙的连通起到重要作用，是原油高产的因素之一。

The researches on core observation, thin section data and the analysis of conventional physical property show that the natural fractures are well developed in Chang 2 reservoir of Panlong Oilfield, Ordos Basin and they are high angle fractures． The fracture filling is mainly calcite and some fractures are not filled with good oil accumulation． Using the abnormal frequency analysis method of permeability, this paper studies the plane variation rules of fractures in Chang 2 reservoir. The result shows that the high yield wells are in the two intervals of the main permeability anomaly values of 5% to 30% and more than 50%． Macroscopic fractures play a bridge role of communicating the effective source rocks of Chang 7 reservoir and Chang 2 reservoir, forming a rich oil accumulation in Chang 2 reservoir． Microfractures can play an important role in matrix pore communication, which is one of the factors of high oil production．

10.6056/dkyqt201201014