DISTRIBUTION PATTERN AND CONTROLLING FACTORS OF HYDROCARBON IN THE 1st MEMBER OF SHUANGYANG FORMATION IN THE MOLIQING RIFT, YITONG BASIN

The Moliqing Rift, located at the southernmost corner of the Yitong Basin, is a second-order tectonic unit of the basin. Upon the logging and oil production data and previous studies, the oil and gas distribution pattern in the 1st Member of the Shuangyang Formation are summarized. There oil and gas mainly occur in the Lower Sand Group Ⅱ of the 1st Member, and are distributed along the faults on the east and west sides of the Kanshan Sag in a plane view. From the northwest boundary to the southeast border of the hydrocarbon-generation depression, there are three primary types of reservoirs,i.e. fault-sealed, lithology-sealed and complex reservoirs. The distribution of oil and gas depends mainly upon the distribution patterns of unconformities, faults and lithofacies, and the dominating factors vary in different tectonic units.