川东涪陵地区大安寨段为典型的超低孔、低渗储层，其非均质性较强，裂缝可作为主要的油气赋存空间。 根据野外露头、钻井岩心、薄片镜下鉴定、扫描电镜分析、成像测井等资料，以及对百余件样品进行了分析实验，认为大安寨段裂缝按成因可划分为构造缝、成岩缝与溶蚀缝等 3 种类型，并详细描述了其主要参数，包括倾角、长度、密度和有效性等。 针对各类型裂缝从多个方面分析了影响裂缝形成的主要因素，得出基质岩性、构造作用和沉积-成岩作用对裂缝的影响均较为明显。 在岩心观察的基础之上利用稳定同位素分析与声发射实验等多种手段对裂缝形成期次做出初步的判断，认为至少存在燕山晚期、喜山早期和喜山晚期 3 期裂缝。

The reservoir of Da’anzhai member in Fuling area, eastern Sichuan Basin, is characterized by low porosity, low permeability and strong heterogeneity, and fracture is the main reservoir space. According to outdoor surface occurrence, core observation, thin section analysis, scanning electronic microscope and image logging, this paper divided fractures into three types by genetic mechanism: structural fracture, diagenetic fracture and dissolved fracture, and fractures are characterized by low inclination, long length and high density. The main controlling factors for each type of fractures are lithology, tectonism and diagenesis. Based on the fracture characteristics, isotope analysis of fracture fillings and the acoustic emission experiment of rocks, it is indicated that the fractures can be divided into three stages at least: the late Yanshanian, the early and late Himalayan respectively.