NOTED ON TYPES OF DELTAIC DEPOSITION OF LAKE BASIN IN SONGLIAO BASIN

Based on history of growing and declining of lake basin, deltas of Early Cretaceous lake basin in Song-Iiao basin are classified into three catagories : 1) Retreated deltas formed during lake transgression. 2) Prograded deltas formed during lake regression. 3) Fan deltas formed between lake transgression and regression. Describing different depositional processes, the diverse patterns of vertical facies sequences are shown as effective criteria for distinguishing the three types of deltas.