A DISCUSSION ON STRATIGRAPHICAL CLASSIFICATION AND LOWER BOUNDARY OF QUATERNARY IN THE THREE-RIVER PLAIN
三江平原第四系划分及下限问题

The Three-River . ( Sanjiang ) Plain is a low-lying swampying alluvial plain formed by three rivers: the Heilongjiang, the Songhuajiang and the Wusulijiang. The lower limit of the Quaternary system in this region can be marked by the closing of the warm-humid climate of the warm-temperate and temperate zones in the Neogene period, and the beginning of the glacial stage climate in the Quaternary.