The glacial geomorphology of the Mackenzie Mountains region, Canada

During the Last Glacial Maximum, the Mackenzie Mountains region was glaciated by three distinct ice sources; the Laurentide Ice Sheet, the Cordilleran Ice Sheet, and independent montane glaciers. Rapid ice sheet thinning of the Laurentide-Cordilleran ice saddle in the south of this region contributed to rapid sea level rise events and influenced the style of deglaciation to the north. The current understanding of the glacial history of the broader region has been established through mapping from aerial imagery and early surveys between the early 1970s to the 2010s. The central portions of the Mackenzie Mountains have not yet been mapped. We present a new glacial geomorphological map for the Mackenzie Mountains region covering over 220,000 km2. This updated geomorphological map will form the basis of future work to reconstruct the former maximum ice extents, flow dynamics, and retreat pattern.

末次冰盛期（Last Glacial Maximum）期间，麦肯齐山脉（Mackenzie Mountains）区域受到三类不同冰源的冰川作用影响，分别为劳伦冰盖（Laurentide Ice Sheet）、科迪勒拉冰盖（Cordilleran Ice Sheet）以及独立山地冰川（montane glaciers）。该区域南部的劳伦-科迪勒拉冰鞍（Laurentide-Cordilleran ice saddle）发生的冰盖快速减薄，曾引发快速海平面上升事件，并对北部区域的冰消作用（deglaciation）模式产生了影响。目前学界对该更广区域冰川历史的认知，均基于1970年代初至2010年代期间的航空影像测绘与早期野外调查成果，而麦肯齐山脉的中部区域至今尚未完成测绘。本研究构建了覆盖面积超22万平方千米的麦肯齐山脉区域全新冰川地貌图（glacial geomorphological map），这份更新后的地貌图将为后续重建区域古最大冰盖范围、冰流动力学及冰退模式的研究奠定基础。