Study On Shale Gas Preservation Conditions Of Wufeng Formation-Longmaxi Formation In Yuyang Block, Southeastern Guizhou

By logging data of Youyang block several field profile and the actual measurement and regional wells were summarized, and the core were measured, combined with the Youyang regional tectonic background, systematically Youyang region Wufeng Formation-Longmaxi shale layer structural features, the Wufeng Formation-Longmaxi formation black shale shale gas preservation conditions.According to the analysis of Youyang region multiple profile exploration and well logging data, summed up the area in six typical tectonic style:back thrust flat arch anticline, disc gentle syncline, symmetric wide syncline, lateral wide syncline and closed syncline and high and steep fault fold. Block parts of the typical structural styles are mainly the following style:back thrust flat arch anticline, disc gentle syncline, symmetric wide syncline, high and steep fault fold.Through the field observation of the field profile, it is understood that the shale in Youyang area is more developed, mainly in the structure of the shear cracks, shear and can be divided into shear and cross section shear. "Plane shear joints" common development in shale formation, intersecting and perpendicular to the stratification or high angle, fracture surface is flat, stable occurrence, slickensides, obviously, a total of two groups, a plane x conjugate shear seam. Section shear joints with low angle of the plane intersection, the degree of development than the plane X type conjugate shear gap. Plane X type conjugate shear joints and shear joints were developed in two groups, the direction and tendency of the planar X type conjugate shear joints were different, and the section shear joints were the same. The shale strata in the study area are mainly based on these two kinds of cracks.Through the rock samples of the acoustic emission test, crack filling analysis and crack staging and supporting, in Youyang shale fracture development is mainly affected by Indosinian movement, Yanshan movement and Himalayan movement period of tectonic movement; through of Southeast Chongqing Youyang region surface and subsurface crack fracture tectonic trace analysis, and fold and fault interpretation of the results, of Southeast Chongqing Youyang region fault and fold formation model are discussed, fracture system of the research area and fold to sum up the mode of formation and evolution.The preservation condition of shale gas is influenced by the factors such as the thickness, the cover layer, the roof and floor, the tectonic movement and the structural style. By means of Youyang region layer on the Wufeng Formation of Ordovician-Silurian Longmaxi group of field reconnaissance, and block multiport parameters well core observation and description. Under the existing knowledge system, and logging data combined restoration of objective layer overlying strata luoreping formation and underlying strata Linxiang group, the Baota group, in order to understand the special purpose layer of shale gas preservation. Then, Dingshi anticline, Tongxi syncline, Chetian syncline and nearby area is divided into class II favorable areas. Xianfeng anticline, Youyang syncline, Ji Gong Ling anticline, Youchou anticline and its nearby area is divided into class ? favorable areas.