The Dalazi Formation in the Songjiang Basin of Jilin Province shows different sedimentary characteristics and evolution during the Early Cretaceous period. The researchers identified four main sedimentary facies: fluvial fan, fan delta, lake, and lake subaqueous fan, with nine subfacies. The sedimentation and evolution of the formation were influenced by local tectonic activities, paleotopography, paleoclimate, and base-level changes. Initially, the basin had fluvial fan and fan delta deposits, but later shifted to lake facies with some lake subaqueous fans. The deposit center moved from Xiaoshahe-Xinfeng to Yangmutun-Shenglitun as the basin expanded southwards.