The Accumulation Characteristics Of Shale Gas In Santanghu Basin,Xinjiang

The paper use petroleum geology 、 basin analysis 、 sequence stratigraphy 、 sedimentology 、 geochemistry 、 organic petrology paleontology heories and methods in combination with the existing data on Santanghu Basin shale gas formation mechanism, Accumulation analyze, through comparing the dominate and abroad research found that shale gas potential Santanghu huge basin. He noted Santanghu basin main from the Mesozoic Upper Triassic and Lower Jurassic source rocks, Paleozoic Permian article, Lake group and Lucaogou lacustrine source rocks, Lower Paleozoic Permian and Carboniferous lacustrine source rocks three sets of hydrocarbon source rocks. The analysis of rock on the scope and depth distribution、abundance of organic matter、 organic matter type、maturity of organic matter、cracks and porosity、 permeability and fragility content of hydrocarbon source material basin that Santanghu basin has shale gas accumulation,basic conditions. From the analysts,we believe that the Jurassic- Triassic hydrocarbon source rocks types mainly Ⅱ2 ~ Ⅲ1 main type, a low-medium maturity; Permian source rocks with type Ⅲ, Ⅱ-Ⅰ2 main type; Carboniferous The main types of organic matter to the Ⅱ type, mainly in the mature stage, and even high maturity. Jurassic source rocks are mainly under conventional Shuixigou group, hydrocarbon center strip Marange Lake depression and depression. Distributed throughout Santanghu Basin shale gas mainly by controlling the distribution of source rocks and crevices distribution reservoirs are well developed cracks and pores, brittle material content above 50%, Triassic source rocks Xiaoquangou main focused on the Han River Springs Lake depression Depression and bars. Article Permian Lake group and Lucaogou lacustrine source rocks are mainly distributed in bars and Malang Sag Lake depression southern edge, most of hydrocarbon potential within the basin best source rocks, followed by Carboniferous, somewhat less for the Jurassic- Triassic. Basin shale gas adsorption are hosted primarily by reservoirs, mainly in the kerogen and shale particle surface or dissolved in kerogen, less free gas content, occurred after generating massive retention in the reservoir. Shale basin in the whole depth of 3500 m or more, layer thickness is about 40m-50 m, is very conducive to storage shale gas. Through log analysis, rock electrical characteristics Santanghu Basin obvious, Permian gas logging abnormal show better Carboniferous gas logging abnormal show active gas measurement component characteristic longitudinal overall performance: Jurassic was "high methane " characteristics; Triassic, Permian was " methane " feature; Carboniferous was " low methane " feature. According to the comprehensive analysis to determine Santanghu Basin shale gas stored in favorable target area is depressed Marange Permian Lucaogou group horse 7 blocks. The results of exploration offer the evidence for developing Santanghu Basin shale gas.