麻黄山地区延安组、延长组储层裂缝特征及识别

Fracture identification of reservoir of Yan’an and Yanchang Formation in Mahuangshan area

麻黄山地区延安组、延长组是典型的低孔、低渗砂岩储层,裂缝是储层的主要渗滤通道,且油气聚集成藏及开发效果与裂缝关系密切。因此,裂缝特征及识别研究是该区储层评价中的重要内容。目前,应用新的测井技术可以有效识别裂缝,但受到资料数量限制,无法进行规模应用。作者从岩心裂缝研究入手,系统分析了储层中裂缝的常规测井曲线响应特征,应用逐步判别分析法对裂缝进行识别,对今后勘探开发具有指导意义。

Yan＇an Formation and Yanchang Formation in Mahuangshan region of southern Ordos Basin are typical sandstone reservoirs with low permeability and low porosity. The fractures are the major filtration passages in the reservoirs and they have close relationship with the result of exploitation and the formation of the reservoir. Therefore, the characteristics and the identifications of the fracture are the key research work to the evaluation of the reservoir in this area. At present, the applications of new logging technique can identify fractures effectively, but they are always confined by the limitation of lacking data, and cannot be used in a large scale. The study starts from the fractures in the core, analyses the behaviour character of normal logging curve of the fractures in the reservoir, identifies the fractures by stepwise discriminant analysis, and builds up the fracture discriminant model according to the core and log parameters. Through the examination of coring samples and actual application, this model has a good effect.