Sedimentary Analysis of the Cretaceous Yingcheng FormationDenglouku Formation in Shuangcheng Area, Northern Songliao Basin

Shallow oil and gas resources in the northeastern region have been preliminarily explored. However, with sustained economic growth driving increasing energy demands, deep oil and gas exploration has gradually become a new focal point. The Denglouku oil reservoir in the Shuangcheng South area of the Songliao Basin is a recently discovered significant deep formation, yet systematic fundamental geological research in this region remains lacking. This study focuses on the third member of the Cretaceous Yingcheng Formation and the two members of the Denglouku Formation in the Shuangcheng area of the northern Songliao Basin. Through single-well facies identification, cross-well profile analysis, and other comprehensive research methods, a five-level sequence stratigraphic framework was established. Three major sedimentary systems were identified: shallow-water delta, braided river, and fan delta, with further subdivisions into subfacies and microfacies. The study clarifies sandstone distribution patterns and the sedimentary facies-reservoir response relationship, providing a geological basis for oil and gas exploration and development. Favorable hydrocarbon accumulation factors are summarized, and exploration recommendations are proposed.