Factors responsible for driving the glaciation in the Sarchu Plain, eastern Zanskar Himalaya, during the late Quaternary

Abstract

Detailed geomorphological investigation supported by field stratigraphy and optical dating enabled us to identify three major events of glaciation in the eastern Zanskar Himalaya (Sarchu Plain). The oldest and most extensive glaciation is the Sarchu Glaciation Stage‐1 (SGS‐1) that pre‐dates the Last Glacial Maximum (LGM) and is assigned to the cold and wet Marine Isotope Stage‐4 (MIS‐4). The second glacial advance (SGS‐2) is optically dated to ∼20 ka and the youngest SGS‐3 is assigned to the 8.2 ka cooling event. Evidence of deglaciation is preserved as outwash terrace gravels and is assigned to the pluvial MIS‐3 and the early Holocene (∼9 ka). Increased strength of westerlies (winter precipitation) and associated temperature decline were responsible for driving the glaciation in the study area, a conclusion that accords well with modern meteorological data showing a reasonable correlation between the modern equilibrium line altitude, enhanced mid‐latitude westerlies (winter precipitation) and winter temperatures. The phases of deglaciation occurred during periods of warmer climatic excursions. Overall a broad correspondence between the Sarchu Plain glaciation phases and northern latitude ice sheet dynamics is suggested, implying that the glaciers in the trajectory of the mid‐latitude westerlies are likely to respond in phase with northern latitude glaciation.

Late Holocene Glacier Dynamics in the Miyar Basin, Lahaul Himalaya, India

“…In contrast to older studies, more recent studies on glacial chronology from the Lahaul region have suggested considerable glacial expansion at the time of the global LGM [76,90]. However, signatures of glacial episodes between MR-I and KH-II are completely missing in the Miyar basin, and the MR-I stage might be related to the Chandra stage proposed earlier in the region given the magnitude of glacier expansion [24,70].…”

“…An early Holocene glacier stage in Lahaul Himalaya is also supported by the Cosmogenic Radio Nuclide (CRN) surface exposure dates from nearby valleys, for example, Rape (9.0 ± 0.1 ka), Sissu (9.5 ± 0.5 ka), Batal (11.4 ± 0.3 ka, and 12.0 ± 0.1) [75]. Additionally, for the Sarchu Plains an early Holocene glacial advance has been put at 8.2 ka based on optical dating [76]. Therefore, our study supports the view that during the early Holocene the Lahaul experienced increased precipitation rather than increased temperatures.…”

The Holocene floods and their affinity to climatic variability in the western Himalaya, India

“…Further, the formation of the relict lake deposits in the trans-Himalaya of the Satluj valley is attributed to the landslides and not to the moraines(Dortch et al, 2009; Phartiyal et al, 2009; Anoop et al., 2012; Draganits et al, 2014). Additionally, GLOFs are known to occur under warm and wet climate(Richardson and Reynolds, 2000;Sharma et al, 2016c) and are often triggered by heavy rain storms(Warburton and Fenn, 1994;Ziegler et al, 2014). Considering the above, we tend to suggest that extreme precipitation and hence LLOFs were the major processes for generating Holocene floods in the Satluj River catchment.…”

Mid–late Holocene fluvial aggradational landforms and morphometric investigations in the southern front of the Shillong plateau, NE India

“…In the Himalayas, aggradational landforms are known to respond sensitively towards climatic and tectonic forcings and hence used extensively to unravel the role of climate (cyclic process) and tectonics (steady-state process) at centennial and multi-millennial time scales (Pratt-Sitaula et al 2004;Juyal et al 2010;Kothyari et al 2016;Sharma et al 2016). For example, it has been argued that valley-wide fluvial aggradation events can be ascribed to climatic forcing whereas incision into the bedrock would represent long-term surface uplift (tectonics) (Hancock and Anderson 2002;Vandenberghe 2003;Bridgland and Westaway 2008).…”

“…Reasonable studies pertaining to the nature and evolution of fluvial landforms from the western (Bookhagen et al 2005(Bookhagen et al , 2006Phartiyal et al 2005;Srivastava et al 2013;Sharma et al 2016) and central Himalayas (Juyal et al 2010;Chaudhary et al 2015;Kothyari et al 2016) exist. Compared to this, such a study from the northeastern Himalaya is scanty (Meetei et al 2007;Srivastava and Misra 2008;Luirei et al 2012) and absent from the Shillong plateau (SP), NE India.…”