Characteristics Of The Shale In Longmaxi Formation Of Silurian In Eastern Sichuan Basin, And Its Reservoir-forming Rule

Shale gas is an unconventional CNG, which generated, accumulated and covered in the same shale system, and consisted in the fracture or the hole, alone or in the unbound state, is also a biogenic and (or) pyrolytic CNG. And it mainly developed in the dark mud shale or high carbon mud shale, with many types like Authigenic reservoir, Adsorb reservoir, Hidden reservoir, and so on. In the shale gas reservoir, CNG exist not only in the shale, but also in the laminated shaped siltstone, silty mudstone, argillaceous siltstone, and sandstone, which is gathered near the source bed after its generation.According to some estimate, the recoverable resources of shale gas in China is about26×1012m3, which is amount to the America. The shale gas reservoir mainly developed in Sichuan, Erdos, Bohai Gulf, Insects, Terek, Tuha, Tarim, and Dzungaria, and also could be found in the marine shale formation, some time oceanal and some time continental shale formation, and the continental formation in China, so that, it has a good future to conduct the shale gas resource exploration.This study focused on the shale of the Longmaxi Formation in the Eastern Sichuan Basin. We measured some sections and cleared up some indoor data, based on the previous studies. This article related to many knowledges in Sedimentology, Petromineralogy, Petroleum Geology and Geochemistry. And the thin section authentication, X-ray diffraction analysis, Mineral fabric analysis, Organic geochemical analysis were used to test the shale, after that, we got the gross feature, microscopic feature, petrologic feature, sedimentary facies, paleontology features, distribution, production capacity of the shale. Viewed all these above, we discussed the accumulation mechanism and accumulation regulation of shale from Longmaxi Formtion in Eastern Sichuan Basin.This study, is based on summarizing predecessors’research and concluding my own understanding, summarized below:(1) Silurian Longmaxi Formation is most of carbonaceous shale clips thin laye siliceous shale, siliceous shale becomes more in Wufeng Formation, mainly are siliceous shale clips carbonaceous shale;(2) Silurian Longmaxi Formation is widely distributed in the eastern sichuan basin area、relatively shallow buried, has better exploration prospect in some palces where have good sealing properties;(3) Longmaxi Formation in the studied areas mainly belong to Shelf-Slope sedimentary Facies and Slope-Deep water basin sedimentary facies. Its source areas are Hannan (paleo-)land, Sichuan northern uplift.