Research On Relation Between Tectonic-thermal Evolution History And Hydrocarbon Generation History Of Carboniferous-Permian In The North Of Songliao Basin

The Songliao Basin received extensive marine deposition in Carboniferous-Permian, and its geothermal field were several changed,when it experienced multi-stage tectonic movements and transformation of superimposed basins. It will be of great significance for deep oil and gas exploration in Songliao Basin that the study for the prototype basin, the basin thermal history, and the thermal evolution of source rocks of Carboniferous-Permian.In this paper, based on the evolutionary history of the basin, we combined various geological data, draw the deposition phase diagram of the study area of Carboniferous-Permian, and resumed the prototype basin on the background of the regional geological structure. Based on the establishment of burial history, using the palaeothermometry, we resumed and reconstructed the thermal evolution history of the northern region of Songliao Basin, focusing on the research of the evolution history and hydrocarbon generation history of the source rock of Carboniferous-Permian, revealed the thermal evolution history and hydrocarbon generation history of source rock of different tectonic units to provide basis for the future exploration.Complex the outcrop, drilling, seismic and various analytical data, we acquaint that Songliao Basin was mainly in shallow marine facies in Carboniferous-Permian. In the late Permian, the seawater exit out of the study area from northwest to southeast, and the study area changed to lake sediments. Combining the analysis of tectonic environment of the rock, we acquaint that the prototype basin of the region was a stable continental margin basin in Carboniferous-middle Permian, and it changed into a depression basin in late Permian. The scope of the prototype basin is much lager than present.Using the palaeothermometry, we analysize some behalf wells of different tectonic units. The results showed that the relationship of vitrinite reflectance and depth of source rock of Carboniferous-Permian in Songliao Bain can be divided into two kinds:two stage and like line. Mingshui terraces, Chaoyanggou terraces, north of Heiyupao depression and the west slope are two stage type, the lagest ancient temperature of which has been achieved in late Permian. Wangfu depression in Bin county, Changchunling anticline, Sanzhao depression, Daqing Changyuan, Gulong depression are like line type, the largest ancient temperature of which has been achieved before K2-E3.We simulate the thermal history of Sishenl well, Du101 well, Shuangshen4 well and the artificial well of the eastern of basin, sing the Basin Mod software. Based on the burial history, we make the simulated Ro and measured Ro to the best fit condition by adjusting the parameters such as temperature gradient and the erosion thickness. The result showed that the structure parts of two stage type of Ro-H experienced hydrocarbon generation process only once, while the structure parts of like line type experienced twice.Synthesizing the sedimentary, stratum thickness, burial depth, organic abundance and other factors, we consider that the favorable areas for exploration are the uplift between the west of Daqing and the depth zone of Xujiaweizi depression and the uplift around the deep zone, the uplift between Xujiaweizi depression and the deep zone of Yingshan depression and the uplift around the deep zone, Heiyupao depression, Mingshui terraces and Suihua depression.