AGES OF THE YELLOW RIVER DELTA IN SHELF REGIONS OF THE YELLOW SEA AND THE BOHAI SEA

There are two different opinions for the formation history of the Yellow River,one postulates that the Yellow River might have come into existence before Tertiary,the other supposes that it joined up into a long river only in the late stage of Upper Pleistocene.The presence of the whole course of the Yellow River is believed to be closely related to the uplifting of the Tibetan Plateau.It is not likely that it would come into being before the high elevation river head was formed.Today's Yellow River is not known to occur during the recession of sea in glacial periods.In the last glacial stage,the climate was very harsh in the area north of the modern estuary of the Changjiang River,that some areas were permafrost and the others barren deserts.At that time,the aeolation was the major exogenic force on the exposed shelf.Begining from 12ka BP,the global climate became warm,resulting in gradual disappear ance of continental glaciers retreat of mountain glaciers,and rise of sea level.Consequently,the Yellow River was replenished with water to become the modern river system.With continued rising of sea level,the Yellow River delta moved continuously towards the west and ushered in the history of human beings.