According to abnormal pressure fluid compartments or expulsion fluid assemblages
a basin can be divided into many accumulating dynamic systems.There are 6 accumulating dynamic systems in Bohai Bay Basin by expulsion expulsion fluid assemblages and 3 accumulating dynamic systems in Yinggehai Basin by abnormal pressured compartrment.The classification of accumulating systems is various according to different criteria
that is:normal pressure
overpressure and low pressure by distribution of fluid pressure systems;external source
internal source and compound source systems by oil source;and open
closed and semi closed systems by sealing condition.Hydrocarbon migrates mainly within particular dynamic systems
and the basic migration model of cross systems is periodic migration along large faults and fluid diapirs.The structural zones associated with large faults and fluid diapirs are favorable to form complex oil and gas zones of multiple accumulating dynamic systems.