Simulation of source rock for hydrocarbon generation and expulsion in finite space and its significance

Simulation of source rock for hydrocarbon generation and expulsion in finite space has been carried out with samples from the Es²₃ sub-section of the Dongpu sag using the hydrocarbon generation and expulsion simulation experimental instrument of type DK-Ⅱ with porosity,temperature and pressure under geological conditions.It has been concluded that the process of hydrocarbon generation and expulsion of source rock can be divided into 4 stages as follows.1)Ro≤0.72%,oil generates slowly and does not expel;2)0.72% R_o 0.80%,oil generates rapidly,but still remains in source rock;3)0.80% R_o 1.00%,oil generation from kerogen has finished or suppressed,and oil transfers from big molecular to small molecular.Oil migrates to and assemblages in the upper and lower adjacent sandstone as well as source rock surface and fracture,which may guide unconventional hydrocarbon exploration in source rock dominant belt in the Dongpu Sag or the other similar basins or sags;4)R_o 1.0%,oil cracks to gas;however,oil does not crack to CH₄ completely and mainly remains in oil even though R_o 2.0% or 2.4%.The studies suggest that petroleum exploration can be carried out in deeper formation.