2009
  • Non-ICIMOD publication
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Relationships between the heights of moraines and lengths of former glaciers in Tibet and surrounding mountains

  • P. Fu
  • C. Yi
  • Summary
Reconstructions of the extent of Quaternary glaciations provide important knowledge of landform evolution on the Tibetan Plateau. The heights of moraines and the lengths of corresponding former glaciers in Tibet and its surrounding mountains were statistically analyzed using values for 141 observations collected from the literature and field measurements. The height of a moraine is defined as the difference between the elevation of the highest point of a lateral moraine and the elevation of the nearby valley bottom. The results show that the height of a lateral moraine is more closely related to the length of the former glacier than with the height of its end moraine. The lateral moraine was preserved better and more accurately represents the original shape of the moraine. The correlation between the height of a moraine and length of a glacier from lateral moraines in arid areas is better than that in maritime areas. This results from better preservation in arid areas. The high precipitation in the maritime areas results in stronger fluvial erosion and mass movement, and consequently is very effective in modifying and/or destroying moraines. The correlation between heights and lengths of lateral moraines is much better for Holocene than for older glaciations. Therefore, the correlation of the heights of Holocene lateral moraines to the lengths of glaciers is helpful for reconstructing the extent of Quaternary glaciation when end moraines are not preserved. This in turn is a first step towards assessing the relative importance of glaciers in landscape evolution across orogens.