Radiometric chronology of Neh-Nar Glacier, Kashmir

• Main Authors: Nijampurkar, V. N., Bhandari, N., Vohra, C. P., Krishnan, V.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: International Glacial Society 1982
• Subjects: QE Geology; Journal of Glaciology
• Online Access: http://repository.ias.ac.in/88924/; http://www.igsoc.org/journal.old/28/98/igs_journal_vol28_issue098_pg91-105.pdf

Surface and core samples of Neh-nar Glacier in the Kashmir Valley have been analysed for the radionuclides 32 Si, 2lO pb, 40 K, and 137 Cs. The lateral and vertical profiles (at an altitude of about 4 140 m) reveal: ( I ) 32 Si activity decreasing slowly from the accumulation zone to 4 050 m altitude and then abruptly towards the snout. (2) Five zones of alternating high and low 2lO Pb activity in the surface samples. (3) An horizon at between 2 and 3 m depth containing 210 Pb activity above natural levels. This horizon is also associated with 1l7 Cs and a maximum in total β activity. The ice sam.les have been dated on the basis of a simplified two-component model, the "fresh" contribution determined by 21O Pb and the old component by 32 Si. The following conclusions can be drawn from these observations: (I) The model age of the snout ice is c. 850 years. (2) The average rate of ice movement in the lower glacier is about 2 m/year, which compares well with the annual movement rate of 2.65 m/year observed since 1974.