Study on formation mode of splitting gas of Minfeng depression

The genesis and the pool forming model of splitting gas in Shengli oilfield are complicated and various.For the ex- ploration of splitting gas pool in the future,an integrated a- nalysis on the genesis and master control elements of split- ring gas pool formation in Minfeng depression is performed, acquired the splitting gas pool forming mode of deep strata. Studies show that the generating amount of gas is subject to the temperature.If the temperature is higher than 160℃, the splitting gas begins to generate in a large amount.Source rocks in 4th segment of Shahejie group are in the range of this temperature,so the segment is a favorable series of stra- ta for the generation of splitting gas.The favorable source- reservoir-caprock assemblage and structural history are necessary for the generation of splitting gas,and the exist- ence of abnormal pressure is of great advantage to the forma- tion of gas field of large and medium scale.The model of hy- drocarbon pool in Minfeng depression is characterized by late generation and late formation,self-generation and self-ac- cumulation,and roof sealing and lateral plugging.