Reservoir Forming Conditions And Exploration Target Area Prediction Of Shale Gas In Yongshun,Hunan

The study area is located in Yongshun County of Hunan province.The exposed strata are mainly Sinian,Cambrian,Ordovician,Silurian,Devonian,Permian,Triassic and Quaternary,especially the Silurian and cambrian.The lower Cambrian Niutitang Formation,Upper Ordovician,five peaks group and the Lower Silurian Longmaxi formation black shale is the objective layer of this work.Niutitangformation,five peak longmaxiformation belong to the deep shelf.The study area is located in the Yangtze paraplatform in southeast margin of Yangtze fold belt and the Jiangnan uplift of the north western edge of the transition zone,in Baojing-Cili fault as the boundary,grade tectonic unit area belonging to the Yangtze fold belt and the Jiangnan uplift,fault and fold more development.In the five peak group-Longmaxi shale kerogen type is a type I;the upper black shale of Niutitang Formation is type I,the type II,are conducive to gas production.Shale organic matter in a mature basic early stage,increased the risk of shale gas emission.Niutitangformation,five peak group-Longmaxi black shale organic carbon content were respectively 5.91%,2.01%.Horizontally,the organic carbon content of black shale is larger than that of dragon syncline,and the content of organic carbon in black shale of West Wing is larger than that of East wing.According to the analysis of the five peak of Longmaxi formation and Niutitang Formation samples X diffraction region of black shale rock,mineral content of brittle minerals are greater than 40%,easy formation of natural fracture under the action of external force and induced fracture,a fractured reservoir for later.The use of volume statistics,the estimation of the amount of shale gas geological resources of Niutitang Formation,the five peak group-Longmaxi depth of500m-4000m 5260.66*10~8m~3.This study selected sand dam-Zhuang anticline west wing,tiger Bay,rolling anticline West Wing for niutitangformation favorable exploration target area.Longjiazhai syncline core,Tsing Ping syncline core five peak group-Longmaxi shale gas exploration favorable target area.