普光气田礁滩相储层裂缝测井识别方法与应用

Fracture Identification Method of Reef-flat Facies Reservoirs in Puguang Gas Field and Its Application

普光气田礁滩相储层具有溶蚀孔洞发育、局部裂缝发育、储层孔隙结构比较复杂、非均质性比较强的特点。储层厚度大、孔隙发育等特点决定了常规双侧向电阻率法等裂缝识别方法适用性差。在岩心观察、微电阻率扫描成像测井的基础上,结合岩心压汞、铸体薄片分析等资料,研究形成了一套针对普光气田礁滩相储层孔隙结构复杂、裂缝张开度低、常规测井响应不明显等地质特征的裂缝识别方法。即采用分岩性序列建立模型消除裂缝影响的反演电阻率曲线识别裂缝和基于普光气田复杂孔隙结构各自的特征识别裂缝。通过与岩心观察和成像测井识别裂缝进行对比,取得了良好的效果,能够在后期为普光气田合理配产提供可靠的地质依据。

Reef-flat reservoirs in Puguang Gas Field had characteristics of corrosive porosity development,local fracture development,complex reservoir pore structure,strong anisotropism.The big reservoir thickness and porosity development induced poor applicability of conventional dual lateral resistivity method for fracture identification.On the basis of core observation and micro-resistivity scanning imaging logging and the core pressure mercury and thin cast analysis,a set of fracture identification methods were formed for complex pore structure of reef-flat reservoirs with the features of low opening fracture and without obvious conventional logging response in Puguang Gas Field.Lithologic sequence was used to establish a model to eliminate fracture affected inversion resistivity curve to identify fractures and based on each feature of complex pore structure characteristics of Puguang Gas Field.By comparison with core observation and imaging logging,good results are achieved.And it provides reliable geological basis for reasonable production allocation in the gas field at the late stage.