黄河源区第四纪地层及古地理环境演化探讨

Approach on the Quaternary Strata and thePalaeogeographical Environmental Evolutionin Source Region of the Yellow River

The Quaternary sediment in source region of the Yellow River has been studied systematically. And combined with analysed data of spore-pollen, 14C dating, micropalaeontological fossils, X-ray diffraction determination in the Quaternary strata, and data of permafrost, the geographic environment of this region during Quaternary has been reconstructed. The climate in Q1 was warm and wet, there grew forests and steppes; The climate tendency in Q2 changed from warm and wet to arid and cold, appearing the Chahaxili glacial epoch; the Climate in Q3 turned continuously to cold. Glacial epoch and interglacial epoch appeared alternately. The early epoch was named the Halatan glaciation; the middle was a interglacial epoch, and the late the Burhanbuda Shan glacial epoch. Environment of sparse woods steppe and steppe have been evolved alternately in Q3. Environment in Q4 is steppe with arid and cold periglacial climate.