Hydrocarbon vertical migration and its controlling factors of Linnan slope belt in Huimin depression.

The vertical distribution of oil and gas in the Linnan slope belt is characterized by (1)4 sets of major oil-bearing strata exist in Qudi horst, (2)oil-bearing horizon is only formed in the Upper S 4 of the southwestern gentle slope, (3)no oil/gas show occurs in Baiqiao-Renfeng burried-hill belt and (4)oil and gas are mainly concentrated in S 2 and S 3 of the down throw side of Xiakou faulted belt. Based on vertical hydrocarbon distribution properties, a systematic study of the geologic factors decided oil's migration along faults was studied. These factors are regional cap rock, the intensities of fault activity, strike-slip properties, the abundant degree of oil source and abnormal formation pressure. Qudi oil field's long vertical distribution properties is the reason for abundant oil source and intense fault activity. The possibility of hydrocarbon vertical migration is very little in slope belts, so the target of exploration should centers on below formations.