川东北元坝地区须三段致密储集层裂缝特征  

Fractures Characteristics in Tight Reservoir of the 3rd Member of Xujiahe Formation in Yuanba Area in Northeastern Sichuan Basin

作　　者：张冲[1] 谢润成[1,2] 周文[1,2] 李毓[3] 王浩[1] 王喻[1] 黎静蓉 

机构地区：[1]成都理工大学能源学院,成都610059 [2]成都理工大学油气藏地质及开发工程国家重点实验室,成都610059 [3]中国石化西南油气田分公司,成都610016

出　　处：《新疆石油地质》2014年第4期395-398,共4页Xinjiang Petroleum Geology

基　　金：国家自然科学基金(41202096)

摘　　要：川东北元坝地区上三叠统须家河组须三段属低孔低渗致密砂岩储集层。据地质、岩心和测井等资料,研究了须三段岩心裂缝的发育特征及常规测井上的裂缝响应特征,结合区域地质构造背景,对裂缝形成控制因素进行综合分析,并以此对须三段裂缝发育程度进行综合评价。研究表明,裂缝成因类型为构造裂缝,且以张性裂缝为主,裂缝多为低角度或水平,有效性高;有效裂缝常规测井响应特征表现为高声波时差和低深浅双侧向电阻率,测井解释裂缝宽度、孔隙度值相对较大。结合地质、岩心及裂缝测井识别结果,认为裂缝发育主要受岩层厚度、断层、岩性和构造变形强度等4种因素综合影响。最后,基于裂缝发育控制因素分析,采用精密网格法进行的须三段裂缝综合评价结果与单井裂缝常规识别结果吻合率为87.9%,与测试产量也具有较高吻合性。The reservoir of the 3rd member of Xujiahe formation in Yuanba area is tight sandstone reservoir with low porosity and low permeability. Based on the core, logging and geological data, the features of fracture development on the core and the response of fractures on the conventional well logging are studied, and the regional geological structure setting is used to research the control factors of fractures, by which the fracture development of the 3rd member is evaluated comprehensively. The study shows that the type of fracture origin belongs to structural fracture dominated by low-angle or horizontal tension fracture, with high effectiveness of it. The fractures are mainly manifested as high interval transit time and low dual laterolog resistivity by conventional well logs, and relatively large width and porosity by log inter- pretation. Combined with the regional geologic data, the core observation and the fracture logging identification results, the fracture development is affected synthetically by layer thickness, fault, lithology and structural deformation intensity. Finally, according to the factors controlling fracture development, by using precision grid to evaluate the fracture in the Yuanba area, the results are in good accordance with the conventional single well identification result at the rate of 87.9%, and also good with the production test result.

关 键 词：四川盆地 元坝地区 须三段 致密储集层 裂缝特征 控制因素 裂缝评价 

分 类 号：TE112.23[石油与天然气工程—油气勘探]