The researchers studied the sedimentary characteristics of the Lower Cretaceous in the eastern part of the pear depression in Songliao Basin. They used logging, drilling, core, earthquake, and analysis data to understand the sedimentary facies evolution. The main sedimentary facies identified were fan delta, braided river delta, meandering river, and lake facies. The study found that the depositional system in the area is complex, with diverse types of sediments, which poses challenges for oil and gas exploration and resource evaluation.