Glaciers And Environment Of Helan Mountain

Helan Mountain as research region, located in the eastern edge of Qinghai-Tibet Plateau, is the boundary between Monsoon climate and the non-monsoon climate and desert and desert grassland. study the paleoglaciation of Helan Mountain has a great significance of take the glacier growth and tectonic movement's relations.In this paper, by means of multiple indexes such as sedimentology, and environmental susceptibility That reflect the environmental change and the adsolute age.By the methods that sampling in the field, sediment analyzing, dating, contrasting in the lab ,and analyzing the sediment characteristics of glacial geomorphology, ascertain the glacial evolution process and so on. Through each stage of the snowline on glacial calculation, Restore glacial actions area temperature and rainfall condition. According of cirques of lu jia tai and zhaobei gully discussed the glacial features helan mountainous area.Helan Mountain preserves the late Quaternary glacial remains, which distribute on the summit area above 2800m a.s.l., and the typical glacial morphology exists in lujiatai region. The glacial series is perfectly indicated by absolute ages. MIS3b,OSL age about 43.2±4.0ka B.P. the last glacial maximum stage, Coverage of loess OSL age 9.3±1.4 ka B.P; late glacial period, OSL age about 12.0±1.1ka B.P. new glacial period OSL age 1.7-3.4 ka B.P; the continental type glacial during the late Quaternary are prove by the Geomorphic characteristics of degeneration cirques in bianquzhi and daguangou .The present ELA in Helan Mountain was 4724±100m, ELA of 2891 m during the MIS3b.ELA of 2983 m during the LGM.ELA of 3060 m during the late glacial period .ELA of 3190 m during the new glacial period. Through the determination of the helan mountain glacial history, test the relation with edge of Qinghai-Tibet Plateau glacial series and Republican movement...