Zhu Zhaoyu
In the past many scientists had, from distinct data, estimated the birthday of the YellowRiver at the Pliocene, the Early Pleistocene, the Middle Pleistocene, or the Late Pleistocene.In this article the author is the first to propose a new position: the Yellow River and itsmain tributaries were formed in 1670-1450 ka B. P., i.e. early-middle Pleistocene, and afterthat 6 terraces and 2 valley flays have developed. The ages (ka B. P.) are as follows: TG,1670--850, T5, 850-470, T4, 470-100, T3,100-10, T2, 10-0.7, T1, 0.7-0.3, high valleyflay 0.3-0.15, lower valley flay 0.15-0. The periods of hydrographic evolution may be di-vided into 4 main stages and 9 substages since the Pliocene.These new conclusions are obtairied on the basis of a host of field investigations along theYellow River and its tributaries, and according to the principle of "paleosol-dating method"suggested by the author.
