白龙江流域全新世泥石流与环境演变的初步研究

A preliminary study on debris flow and environmental evolution in Holocene at the Bailongjiang River Valley

根据黄土—古土壤沉积序列研究和野外考察资料并结合放射性14 C测年 ,初步确定嘉陵江上游白龙江流域全新世泥石流共分三期 ,时代分别为 70 0 0 -60 0 0aBP、4 0 0 0aBP和 2 0 0 0aBP .研究表明 ,泥石流频繁爆发于古气候由寒冷向温暖转换的波动时期 .

Six typical Holocene debris flow sections were studied in detail at the Bailongjiang River system, which is located in the eastern margin of Qinghai-Xizang Plateau. Based on the stratigraphy of loess-paleosol sequences,\+\{14\}C datings and debris flow deposition, the evolution of debris flow in Holocene can be divided into three stages, which are around 7 000 aBP to 6 000 aBP, 4 000 aBP and 2 000 aBP respectively. The debris flow erupted frequently at the shift of relative cold climate to warm climate.