Research Of Hydrocarbon Generation And Expulsion Characteristics And Source Evaluation Of Periphery Sags Of Hailaer Basin

There are 14 sags in periphery Hailaer Basin, the area is near 20,000 km2, in which Hulunhu sag , Huhehu sag and Bayanhushu sag have larger area and deeper depth, develop hydrocarbon source rock in Damoguaihe group, Nantun group and Tongbomiao group, have good hydrocarbon generation condition, and can be seen various oil and gas display. With continuous development of exploration, periphery sags will become main area of next step exploration, therefore, it is necessary to research basic geochemical characteristics of hydrocarbon source rock and distribution range of hydrocarbon kichten and hydrocarbon generation and expulsion capacity in detail , for offering scientific foundation to next exploration decision.The thesis conducts detailed evaluation of hydrocarbon source rock in periphery sags of Hailaer Basin. Firstly, based on Pr/Ph, periphery sags are divided into three types of sedimentary water environment: brackish-saline sedimentary environment represented by Bayanhushu sag, paludal facies-lake sedimentary environment represented by Huhehu sag, and fresh sedimentary environment represented by Dongming sag respectively. Then based on good correlation of TOC and S1+S2, put up hydrocarbon source rock evaluation criterion by different sedimentary environment separately , the lower limit of TOC of brackish-saline lake facies , fresh lake facies and paludal lake facies is 0.4%,0.8% and 1.4%. Lastly compute TOC by use of well log curves, combined TOC plane maps, organic material type maps and Ro evaluation maps of each layer, determine hydrocarbon kitchen of each layer and sag. In the same time, conduct geochemical evaluation of coal layer of Huhehu sag and Yimin sag, the result is the distribution range of coal layer in Huhehu sag is large, the thickness is relatively huge, the abundance is relatively high, the mature area is relatively large and gas generation potential is relatively great.The thesis conducts research of hydrocarbon generation and expulsion characteristics in periphery sags of Hailaer Basin. Firstly determined the corresponding depth of oil generation threshold, hydrocarbon expulsion threshold and oil generation peak based on geochemical indices such as Ro,Tmax,OEP,"A"/TOC and (S1+S2)/TOC, then studied hydrocarbon generation and expulsion characteristics and hydrocarbon expulsion efficiency of organic material of different sedimentary environment and different types in Hailaer Basin in use of HI and S1/TOC.