OBSERVATIONS ON THE QUATERNARY GEOLOGY OF THE LADAKH RANGE, NORTHWEST INDIAN HIMALAYA |
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| Authors: | WAMitchell |
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| Institution: | W. A. Mitchell 1,P. Coxon 2 |
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| Abstract: | Ladakh is a critical area in a determination of the nature of Himalayan glaciation as it lies north of the arid area of Zanskar, where the glacial extent was limited through much of the Late Pleistocene, and south of the Karakoram Range which remains the most heavily glaciated area outside the polar areas and was a centre of extensive glaciation during the Pleistocene.This variation in glacial style and extent across the Himalaya may reflect the interplay between monsoon driven south\|westerly air masses from the Indian Ocean and the westerly air masses from the Mediterranean/Black Sea areas. This paper reports on the first detailed geomorphological observations from within the Ladakh Range and demonstrates the former existence of large glaciers with a number of distinct limits to allow a first approximation of the glacial sequence. Samples for OSL age estimates are currently being processed to constrain a chronostratigraphy. No evidence has been observed for glaciation within the main Indus valley, but large (>80m high) moraine ridges indicate the former existence of glaciers entering from the southern tributary valleys of the Ladakh Range, descending to altitudes of c. 3500m.The Nimu glacier diverted the Indus southwards to erode a new valley with the abandonment of its former valley that can be traced westwards. In the tributary valley north of Leh, impressive termino\|lateral moraine ridges appear to lie on top of older weathered smaller moraine ridges, suggesting a more complex glacial sequence than previously reported. |
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| Keywords: | Ladakh glaciation catastrophic floods OSL age estimates |
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