Thermal Evolution History And The Geochemical Characteristics Of Hydrocarbon Source Rocks In Modamuji Depression, Hailaer Basin

The paper aimed at some practical matters of Modamuji Depression, Hailaer Basin, such as low degree of exploration and development and lack of further research about hydrocarbon source rocks geochemical characteristics and thermal evolution history. Based on the predecessors'studies, division and correlation of strata with the support of geophysical well logging, seismic, core datas. And then discussion the process of sedimentary and tectonic evolution of Modamuji Depression, which can be divided into three phases, for example:the period of Kit and Kin deposition is fault stage, the period of Kid deposition is depression stage and K1y and K1q deposition period is shrinking stage.Defined the sedimentary conditions and the main position of hydrocarbon source rocks, Modamuji Depression.Trace elements analysis shows the continental fresh water sedimentary environment of sedimentary conditions which can determined the standard of organic matter abundance evaluation of hydrocarbon source rocks, Modamuji Depression. Analysis of hydrocarbon source rocks geochemistry characteristics by Rock-Eval, TOC, Kerogen microscopic examination, RO, Chromatogram of saturated hydrocarbon and confirm that the hydrocarbon source rocks from Kid is overall high which reaches up to the criteria of medium-good hydrocarbon source rocks, organic matter is dominated by ?2-?, but the thermal evolution is generally low which belongs to poor hydrocarbon source rocks and hydrocarbon-generating potential is relatively low with immature to low mature stage. Kin2 hydrocarbon source rocks belongs to medium stage which has a relatively high abundance of organic matter and organic matter is dominated by ?2-? and reached mature hydrocarbon generation stage and potential of hydrocarbon generation is relatively high. Which is the best hydrocarbon source rocks of Modamuji Depression. Kin1 is the poor hydrocarbon source rocks which is relative lowest abundance of organic matter and organic matter is ?2-? and belongs to mature hydrocarbon generation stage and poor generation hydrocarbon potential.Recovery of two denuded strata thickness and establish model of burial history by trend of formation thickness and vitrinite reflectance method with the support of seismic and RO. Simulation of hydrocarbon source rocks thermal evolution history regard Ro as paleotemperature under the constraintion of present geothermal field. It shows that Kin hydrocarbon source rocks reached maximum palaeogeothermal in the late cretaceous, mainly hydrocarbon generation period is 104.0-75.0 Ma. Basin at the cooling stage after paleogene and the hydrocarbon generation process to stop. Comparative analysis the thermal evolution history of Modamuji depression with others sags and summarize that study area hydrocarbon hydrocarbon source rocks' thermal evolution degree of Modamuji depression is lower than southern Buir and Wuerxun sag.