The Innuitian Ice Sheet: configuration, dynamics and chronology

摘要: Abstract Portrayal of North American ice cover during the Last Glacial Maximum is dominated by Laurentide Ice Sheet, leaving little detail for adjacent Innuitian Sheet (IIS). Four decades geological fieldwork across Queen Elizabeth Islands now warrant specific treatment IIS, including its chronology, configuration, dynamics and retreat. This reconstruction relevant to sedimentary history Arctic Ocean high latitude climate forcing. The IIS was composed both an alpine lowland sector. advance sector occurred as recently 19 14 C ka BP. Geological evidence configures outflow from divides that produced several palaeo-ice streams, one extending northwestward Canadian Archipelago polar continental shelf. Retreat commenced along southwest margin ∼11.6 However, most sheet remained on shelf Younger Dryas. By ∼10 C ka BP, marine-based experienced widespread calving through western central archipelago in response Holocene warming ongoing eustatic sea level rise. penetrated eastern 8.5 gutting IIS. Regional isobases record glacioisostatic signature sheet, are congruent with primary evidence. delayed buildup out-of-phase growth occasioned climatic glacio-eustatic forcing region. Recent modelling experiments reinforce hypothesis culminated a split jet stream temporarily favoured augmented precipitation