Radiometric age of the snout ice of Nehnar glacier

• Main Authors: Bhandari, N., Bhatt, D. I., Nijampurkar, V. N., Singh, R. K., Srivatsava, D., Vohra, C. P.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Indian Academy of Sciences 1981
• Subjects: QE Geology; ice core
• Online Access: http://repository.ias.ac.in/88923/; http://repository.ias.ac.in/88923/1/88923.pdf; http://www.ias.ac.in/j_archive/epsci/90/3/227-235/viewpage.html

The surface ice taken from the snout of the Nehnar glacier (Kashmir) in western Himalaya has been dated using radioisotopes 32 Si and 210 Pb to be 500 years. Based on the age distribution of ice and the expected activity of 32 Si in the fallout, the average rate of glacier movement over a period of the last few centuries is estimated to be about 6 m/yr. The data obtained on 32 Si and 210 Pb activities in the surface ice samples in the ablation zone support our previous observation about the existence of five zones of alternately high and low activity of 210 Pb, which probably is a consequence of complex dynamics of Nehnar glacier. The vertical profile of 210 Pb activity in an ice core correlates directly with the total beta activity. This radioactive horizon at an altitude of 4140 m appears to be located at a depth of 10-12m, which is lower compared to the 2-3 m observed earlier at an altitude of 4150 m.