Evolution and Control of Oil Distribution of the Transition Zone in the Central Anticline Transformation Belt,Dongying Sag

According to the analyses of fault attitudes and arrays,a complex transformation belt is recognized in the central anticline,Dongying Sag.Research shows that there is significant difference between the eastern and western part of the central anticline because of the existence of the transformation belt.In different geological periods,the transformation belt consists of different transfer faults.From the late Es4 to Es 2 period,Shengtuo transfer fault accommodated different tectonic deformations in the central anticline.From the Es1 to Nm period,Ying 66-1 fault was the major transfer fault.Major transfer faults in the transformation belt has obvious normal dip-slip components.Experiments show that shale smear formed by transfer faults is far better than that in normal faults.Fault dip is negatively correlated with the height of oil column,while normal stress of faults positively correlated with oil column height.Normal stress is in the range of 7 to 20 MPa.The distribution of oil and gas around the transfer fault mainly occurred in the footwall.Because of strong activities of transfer faults,hydrocarbon in fransition zone is richer than other parts of the central anticline structure.