Late Quaternary glaciation in the Nun-Kun massif, northwestern India

Abstract

The late Quaternary glacial history of the Nun-Kun massif, located on the boundary between the Greater Himalaya and the Zanskar range in northwestern India, was reconstructed. On the basis of morphostratigraphy and Be-10 dating of glacial landforms (moraines and glacial trimlines), five glacial stages were recognized and defined, namely: (i) the Achambur glacial stage dated to Marine Oxygen Isotope Stage 3 to 4 (38.7-62.7ka); (ii) the Tongul glacial stage dated to the early part of the Lateglacial (16.7-17.4ka); (iii) the Amantick glacial stage dated to the later part of the Lateglacial (14.3ka, 11.7-12.4ka); (iv) the Lomp glacial stage dated to the Little Ice Age; and (v) the Tanak glacial stage, which has the youngest moraines, probably dating to the last few decades or so. Present and former equilibrium-line altitudes (ELAs) were calculated using the standard area accumulation ratio method. The average present-day ELA of approximate to 4790m above sea level in the Greater Himalaya is lower than those in the Ladakh and Zanskar ranges, namely 5380 and approximate to 5900m a.s.l., respectively. The ELA in the Zanskar range is higher than in the Ladakh range, possibly due to the higher peaks in the Ladakh range that are able to more effectively capture and store snow and ice. ELA depressions decrease towards the Ladakh range (i.e. inner Plateau). Peat beds interbedded with aeolian deposits that cap the terminal moraine of Tarangoz Glacier suggest millennial-time-scale climate change throughout the Holocene, with soil formation times at c. 1.5, c. 3.4 and c. 5.2ka, probably coinciding with Holocene abrupt climate change events. Given the style and timing of glaciation in the study area, it is likely that climate in the Nun-Kun region is linked to Northern Hemisphere climate oscillations with teleconnections via the mid-latitude westerlies.