Palaeoglaciology of the Newfoundland Ice Sheet Complex, Canada, reconstructed using the glacial geomorphological record and cosmogenic isotope surface exposure dating. While the relationship between climate fluctuations and ice sheet dynamics remains unclear there is a need for new insights into the role of ice sheets within the global climate system. One method of understanding climate change is to reconstruct palaeo-ice sheets. This allows us to examine ice sheet behaviour over the long timescales of ice sheet evolution and can provide important insights into how ice sheets may respond to future climate change. The Newfoundland Ice Sheet (NIS) is of particular significance in this regard. It was located on the fringes of the Atlantic Ocean and the Laurentide Ice Sheet (LIS). Therefore the NIS was likely influenced by a number of external and internal drivers, including configuration changes in the LIS, ice stream activity, fluctuations in sea level and oceanic circulation and climate signals from the wider Amphi-North Atlantic. Newfoundland is therefore a key location for investigating ice sheet response to a number of forcing mechanisms. An established ice sheet reconstruction technique is the mapping and analysis of glacial landforms. This record can be used to establish relationships between ice sheet behaviour and a range of forcing mechanisms. Here we present new mapping based on our interpretation of SPOT satellite imagery, Digital Elevation Models and bathymetric imagery of Newfoundland. Our new database of ~150,000 individually mapped subglacial bedforms of glacial lineations and ribbed moraines significantly increases the known landform record in this region. We report our attempt at unravelling this record using a glacial inversion approach and flowset analysis, which separates ice flow patterns into snapshots of ice sheet events. To facilitate greater radiometric control of the deglacial behaviour of the NIS, we report new cosmogenic exposure ages from several sites around southeast Newfoundland. These ages will be combined with existing cosmogenic records to help temporally constrain our ice sheet reconstruction.
|Conference|| XIX International Union for Quaternary Research Congress|
|Period||26/07/15 → 2/08/15|
- Newfoundland Ice Sheet
- Subglacial bedforms