Sequence Stratigraphic Framework and Sedimentary Filling Characteristics of Chaganhua Southern Sub-sag of South Songliao Basin in the Faulted Period

Using the combination of drilling sedimentary cycle and seismic reflection structure, the core, logging, and logging data have been used to clarify the purpose of the sequence stratigraphic framework and sedimentary filling of Chaganhua southern subsag.There are three third-order sequences and six sequence interfaces in the stratum of Shahezi-Yingcheng formation.Three types of sedimentary facies, six sedimentary subfacies and ten types of sedimentary microfacies are developed in the sequence framework.The sequence development and evolution of the sedimentary system are relatively complete.It has been affected by the weakening activity of basin-controlling faults. SQ1 is mainly inshore subaqueous fans, and the fan delta deposition has gradually developed in SQ2. While the fan delta spreads broadly, with the lacustrine range expanding in SQ3. Based on the above study, the Shuang-10 well has been deployed and implemented, with a good oil and gas display.In Chaganhua southern sub-sag, the new hydrocarbon-bearing strata of the Shahezi formation also has been discovered, which is instructive for the exploration of the new strata of the Shahezi formation in the southern part of Changling depression.