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We present a glacial geomorphological map at a scale of 1:200,000 of the Maidika region in the southeastern part of the central Tibetan Plateau covering 13,600 km2. Based on the 90 m resolution SRTM elevation model, the 30 m resolution ASTER GDEM elevation model, and the Landsat ETM+ satellite imagery of 30/15 m resolution, we have mapped glacial valleys, marginal moraines, glacial lineations, and hummocky terrain. Glacial landforms occur frequently and indicate extensive past glaciation with alpine style valley glaciers as well as more extensive ice fields. Of particular interest is the presence of glacial lineation swarms, which is unusual for the Tibetan Plateau glacial landform record. Based on the distribution of glacial landforms, we present a generalized maximum glacial extent reconstruction covering 6045 km2or 44% of the map. [ABSTRACT FROM PUBLISHER]

In this article, we present a map of the glacial geomorphology of the Altai and Western Sayan Mountains, covering an area of almost 600,000 km2. Although numerous studies provide evidence for restricted Pleistocene glaciations in this area, others have hypothesized the past existence of an extensive ice sheet. To provide a framework for accurate glacial reconstructions of the Altai and Western Sayan Mountains, we present a map at a scale of 1:1,000,000 based on a mapping from 30 m resolution ASTER DEM and 15 m/30 m resolution Landsat ETM+ satellite imagery. Four landform classes have been mapped: marginal moraines, glacial lineations, hummocky terrain, and glacial valleys. Our mapping reveals an abundance of glacial erosional and depositional landforms. The distribution of these glacial landforms indicates that the Altai and Western Sayan Mountains have experienced predominantly alpine-style glaciations, with some small ice caps centred on the higher mountain peaks. Large marginal moraine complexes mark glacial advances in intermontane basins. By tracing the outer limits of present-day glaciers, glacial valleys, and moraines, we estimate that the past glacier coverage have totalled to 65,000 km2(10.9% of the mapped area), whereas present-day glacier coverage totals only 1300 km2(0.2% of the mapped area). This demonstrates the usefulness of remote sensing techniques for mapping the glacial geomorphology in remote mountain areas and for quantifying the past glacier dimensions. The glacial geomorphological map presented here will be used for further detailed reconstructions of the paleoglaciology and paleoclimate of the region. [ABSTRACT FROM PUBLISHER]

The glacial geomorphology of the central Tibetan Plateau was mapped over 285,000 km². Here we present a map covering 135,000 km² at a scale of 1:660,000. The glacial geomorphology was mapped using 15 and 30 m resolution Landsat 7 ETM+ satellite imagery, a 90 m resolution SRTM digital elevation model, and satellite and aerial images displayed in Google Earth. Four landform categories were discernible and mapped; glacial valleys, marginal moraines, glacial lineations, and hummocky terrain. The mapped landforms indicate multiple glacial advances of valley and piedmont glaciers. The mapped landform record lends no support to individual ice centres having coalesced to form a plateau-wide ice sheet. [ABSTRACT FROM AUTHOR]