火山岩孔隙–裂缝型储层特征与渗流叠加效应——以准噶尔盆地西缘排66地区为例

Abstract

春风油田位于准噶尔盆地西缘，17口探井钻遇孔隙–裂缝型火山岩油藏，其中4口探井获得了工业油流，为扩大勘探成果，开展了高产机理研究。研究发现，春风油田石炭系火山岩高产有利条件为：储层为火山凝灰岩，岩心含油级别为油斑级，储层裂缝发育，地下原油黏度较低。在分析高产原因的过程中，发现了孔隙–裂缝渗流叠加效应。即孔隙–裂缝沟通后，产生了由于优于单纯孔隙型储层或单纯裂缝型储层的开发效果。孔隙–裂缝叠加渗透率是测井解释储层渗透率的多倍，为采用水平井和长井段压裂提供了理论依据。 Chunfeng Oilfield was located in the West Edge of Junggar Basin, with 17 exploratory wells drilled in pore- fracture type reservoirs of Volcanic Rock, among which 4 exploratory wells obtained industrial oil flow. To expand exploration results, high yield mechanism research is developed. Research shows that, the advantages for high yield conditions of Volcanic Rock in Chunfeng Oilfield are: volcanic tuff reservoir, core oil grade with oil spot, reservoir fractures and lower underground oil viscosity. In this process, pore-fracture seepage additive effect has been discovered. Pore-fracture produced better development effect than both simple pore and fracture. Pore-fracture additive permeability is many times the log interpretation permeability, and it provides theoretical basis for horizontal well and long channel fracturing.