川西坳陷大邑构造须三段储层裂缝类型及控制因素

Types and controlling factors of fractures for the third Member of Xujiahe Formation
in Dayi structure, west Sichuan Depression

刘崇瑞 颜丹平 李书兵

中国石化胜利油田分公司石油开发中心有限公司，山东 东营 257000 中国地质大学（北京）地球科学与资源学院，北京 100083 中国石化西南油气分公司勘探开发研究院，四川 成都 610000

Petroleum Development Center Limited Company, Shengli Oilfield Company, SINOPEC, Dongying 257000, China School of Geosciences and Resources, China University of Geosciences, Beijing 100083, China Research Institute of Exploration and Development, Southwest Oil and Gas Company, SINOPEC, Chengdu 610000, China

川西坳陷大邑构造须家河组三段储层岩性以中细粒碎屑石英砂岩为主，孔隙度、渗透率很低，为典型的低渗透砂岩储层，裂缝对储层的储集和渗透能力具有重要影响，因此，该区裂缝发育特征及其控制因素的研究在储层油气资源的开发和评价中起着重要作用。文中以岩心裂缝观测和岩石力学实验数据为主要依据，对该区须三段储层的裂缝类型及发育特征进行描述和分析，探讨了构造裂缝发育的控制因素。研究表明，该区须三段低渗透砂岩储层主要发育构造裂缝、成岩裂缝和异常高压裂缝3种类型，其中构造裂缝最发育，主要受构造应力场、构造位置和岩石力学性质等因素控制，对油气的形成与分布影响最大。

The reservoir of the third Member of Xujiahe Formation in Dayi structure of west Sichuan Depression is mainly fine grain quartz sandstone with very low porosity and permeability. This member is low permeability sandstone reservoir and fracture has an important impact on the storage and permeable property of reservoir. Therefore, the research on the fracture characteristics and controlling factors plays an important role in the oil and gas resource exploitation and assessment. Based on core observations and the experimental data of rock mechanics, this paper described and analyzed the type and developmental characteristics of structural fractures in the third Member of Xujiahe Formation in this area. On this basis, it discussed the controlling factor of structural fractures. Study shows that the major type of fracture in the low permeability sandstone reservoir are structural fracture, diagenetic fracture and abnormal high pressure fracture. In them, structural fractures are main fractures, which greatly affect on oil and gas formation and distribution. The development of structural fracture is controlled by tectonics stress field, tectonic position and mechanical properties of rocks.

10.6056/dkyqt201401006