The last glaciation of Marvin Peninsula, northern Ellesmere Island, High Arctic, Canada

• Published in: Canadian Journal of Earth Sciences
• Main Author: Lemmen, Donald S.
• Format: Article in Journal/Newspaper
• Language: French
• Published: Canadian Science Publishing 1989
• Subjects: General Earth and Planetary Sciences; Arctic; Ellesmere Island; Canada; Marvin Peninsula; glacier*
• Online Access: http://dx.doi.org/10.1139/e89-220; http://www.nrcresearchpress.com/doi/pdf/10.1139/e89-220

The limit of the last glaciation on Marvin Peninsula, northernmost Ellesmere Island, is recorded by extensive ice-marginal landforms and early Holocene glaciomarine sediments. While glaciers occupied most valleys on the peninsula, other areas remained ice free, as did most of the adjacent fiords. Beyond the ice limit, sparse erratics and degraded meltwater channels within weathered bedrock are evidence of older, more extensive glaciation(s). Shorelines and marine shells 50 m above the limit of the Holocene sea along the north coast relate to these older glacial events.Thirty-four new radiocarbon dates provide a chronology of ice buildup and retreat. Glaciers reached their limit after 23 ka, and locally as late as 11 ka. This was achieved by both expansion of existing glaciers and accumulation on plateau and lowland sites, which are presently ice free. Late Wisconsinan climate was characterized by cold and extreme aridity. Five dates ranging from 11 to 31 ka BP on subfossil bryophytes suggest that ice-free areas were biologically productive throughout the last glaciation. Ice retreat and postglacial emergence had begun by 9.5 ka and was associated with a marked climatic amelioration. The deglacial chronology confirms a pronounced disparity in the timing of ice retreat on the north and south sides of the Grant Land Mountains.