Glacial geomorphology of the Maidika region, Tibetan Plateau

ABSTRACTWe 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 km2 or 44% of the map.

摘要：本研究针对青藏高原中部东南部的迈迪卡（Maidika）地区，编制了比例尺为1:200000的冰川地貌图，研究区覆盖面积达13600平方千米。本研究依托90米分辨率的SRTM（Shuttle Radar Topography Mission，航天飞机雷达地形测绘任务）高程模型、30米分辨率的ASTER GDEM（Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model，高级星载热发射与反射辐射计全球数字高程模型），以及分辨率为30/15米的Landsat ETM+（陆地卫星增强型专题制图仪）卫星影像，完成了冰川谷、边缘冰碛、冰川流线与丘状地形的解译与制图工作。该区域冰川地貌广泛发育，指示过去曾存在以阿尔卑斯式山谷冰川为主、且分布范围更广的冰原。尤为值得关注的是，区域内发育有冰川流线群，这一现象在青藏高原的冰川地貌记录中较为罕见。基于冰川地貌的分布特征，本研究重建了该区域的最大冰川覆盖范围，其面积达6045平方千米，占制图区域总面积的44%。