North Qilian Corridor Area Carboniferous Stratigraphic Classification And The Relationship Of Oil And Gas Research

The study area is located in the northern qilian mountain, from the west to the east mainly include:the JiuQuan basin, the MinLe basin and the WuWei basin, which collectively known as the Corridor District. In WuWei basin, each group is complete and the deposition is thickness, in the JiuQuan basin and MinLe basin missed part of the group, the deposition is thinner.This article is based on the former research, and through the detailed observation and measurement of the24corridor Carboniferous outcrop, collected a large number of lithology, tectonic and palaeobios material. By Using the methods of lithostratigraphy division,age stratigraphic division and biological stratigraphic division, we divided the stratum of Corridor District detailedly, and by combining the Variation Characteristics and the relationship of the subject reservoir and the different sign of stratigraphic division, divided the carboniferous system into:Qianheishan Group、Chouniugou Group、Jingyuan Group、Yanghugou Group and Taiyuan Groop from the bottom to top. Finding that the carboniferous system in Corridor District is gradually become the thick from west to east. And then we established the change rule of stratum in horizontal of carboniferous system in Corridor area.Based on a large number of thin section data and geochemical data, using a variety of analytical methods, we have done a thorough research about the Hydrocarbon source rock, Reservoir stratum, Source-reservoir-cap Assemblage. Through the research about organic matter type, organic matter abundance, and thermal evolution of the Hydrocarbon source rock, we finally got a conclusion: Carboniferous Hydrocarbon source rock has low abundance, the kerogen type is Type III, and organic matter evolution stage of high maturity over-matures stage. A comprehensive analysis shown that the Corridor District Carboniferous hydrocabon source rocks are poor; the research about physical characteristics and the pore types of reservoir rock which show that the reservoirs thologic characters are dense, pores type is intergranular dissolution pores, the porosity and the permeability are small, low porosity and permeability reservoir. After the research about reservoir cap assemblages and their relations, we trust that the Carboniferous has several sets of good combination of reservoir, with a certain amount of oil generation potential.