Study on Glacial Erosion Surface of the Southeast of Qinghai-Xizang Plateau Using Cosmogenic Isotopes Dating

  • 1. Geographical Department, Jiangsu Institute of Education, Nanjing, Jiangsu 210013;
    2. Geographical Science College of Nanjing Normal University, Nanjing, Jiangsu 210097

Received date: 2003-01-13

  Revised date: 2003-04-12

  Online published: 2004-01-20


With the development of the technique of cosmogenic isotopes dating, the formation age of glacial surface can be calculated now. Its principle is that the cosmogenic isotope concentration in the surface rock is a function of age, erosion rate and uplift rate of plateau. Samples of X8 and X9 are taken from the up-surface of glacial boulder in Kuzhao-Shangdui. Sample of X6 is taken from the up-surface of roche moutonnee in valley of the north of Mountain Tuer. The concentration of the cosmogenic isotope 10Be can be got from measure and calculation. According to field exploration, the rock surface where samples X8 and X9 are taken from is erosed about 9 cm in the exposure age t. It means that the erosion rate is about 9/t (cm·a). Then, the t (133.4 ka) can be calculated. Because having the same geographical environment, the rocke moutonnee has about the same erosion rate with the rock. The t (18.5 ka) can be calculated. The study shows that the glacier boulder was formed in 133.4 ka B.P. and the roche moutonnee was formed in 18.5 ka B.P. It can be concluded that Daocheng ice cap was about current in 133.4 ka B.P. (stage 6 of oxygen isotope of deep sea) and the glaciation in the valley occurred about in 18.5 ka B.P.(stage 2 of oxygen isotope of deep sea). The same result coming from two samples X8 and X9 taking from same glacier boulder, and the result from X6 being in concordance with field exploring show that the cosmogenic isotopes dating technique is a effective method in dating surface of landforms.

Cite this article

XU Xiao-Bin, WANG Jian, ZHU Ji, JIANG Hong-Tao, YANG Yi-Qing . Study on Glacial Erosion Surface of the Southeast of Qinghai-Xizang Plateau Using Cosmogenic Isotopes Dating[J]. SCIENTIA GEOGRAPHICA SINICA, 2004 , 24(1) : 101 -104 . DOI: 10.13249/j.cnki.sgs.2004.01.101


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