Glacial geomorphology of the northwest Laurentide Ice Sheet on the northern Interior Plains and western Canadian Shield, Canada

The majority of the Northwest Territories of mainland Canada was covered by the Laurentide Ice Sheet during the Last Glacial Maximum. The increasing coverage of high resolution remotely sensed data provides new opportunities to map the glacial geomorphology and study the glacial history of this remote location. Here we present a comprehensive map of glacial landforms within the northern Interior Plains and adjacent areas of the Canadian Shield, comprising around 6% of the Laurentide Ice Sheet bed. Twelve landform types were mapped from the high resolution ArcticDEM: ice flow parallel lineations, subglacial ribs, crevasse-squeeze ridges, major and minor moraine crests, hummocky terrain complexes and ridges, shear margin moraines, major, minor and lateral and submarginal meltwater channels, esker ridges and complexes, glaciofluvial complexes, perched deltas, raised shorelines and aeolian dunes. Together, these landforms provide a record of the highly dynamic behaviour of the northwest sector of the Laurentide Ice Sheet.

末次盛冰期（Last Glacial Maximum）期间，加拿大本土的西北地区绝大部分区域被劳伦泰德冰盖（Laurentide Ice Sheet）所覆盖。高分辨率遥感数据的覆盖范围持续扩大，为这一偏远区域的冰川地貌制图与冰川演化历史研究提供了全新契机。本研究绘制了加拿大内陆平原北部及加拿大地盾（Canadian Shield）毗邻区域内的冰川地貌综合图件，该区域约占劳伦泰德冰盖基床总面积的6%。本研究基于高分辨率北极DEM（ArcticDEM）共识别并绘制了12类冰川地貌：冰流平行线理、冰下肋状地貌、冰裂挤压脊、主次冰碛脊、丘状地貌复合体与脊状地貌、剪切边缘冰碛、大型、小型、侧缘及亚缘融水水道、蛇形丘脊及其复合体、冰缘冲积复合体、悬置三角洲、抬升岸线与风成沙丘。上述各类冰川地貌共同记录了劳伦泰德冰盖西北区块高度动态的演化特征。