Abstract
The former Newfoundland Ice Sheet was situated on the fringes of the northwest Atlantic Ocean and the Laurentide Ice Sheet (LIS) during the last glaciation. This location suggests Newfoundland is a key location for examining ice sheet response to a number of internal and external forcing mechanisms, including configuration changes in the LIS, ice stream activity, changes in oceanic and atmospheric circulation and fluctuating sea levels. An established approach used to reconstruct former ice sheets is to use a remote sensing approach to map the
glacial geomorphology. Analysis of this record can be used to decipher the dynamics, extent, retreat patterns and configuration changes of the ice sheet throughout its evolution. Here we present new mapping based on our interpretation of SPOT satellite imagery and digital elevation models across Newfoundland as well as swath bathymetry from several locations offshore. Our new database consisting of ~150,000 individually mapped subglacial bedforms
which includes glacial lineations and ribbed moraines significantly increases the known landform record in this region. We illustrate how this data is being used to reconstruct this ice sheet using flowset analysis to separate discrete ice flow patterns into snapshots of ice sheet behaviour through time. Although this technique provides a relative chronology of ice sheet events, if we are to accurately explore former ice sheet variability and investigate links between
ice-sheet fluctuations established by this mapping programme greater radiometric control of ice-sheet events is required. To facilitate this we report forty new cosmogenic exposure ages (10Be and 36Cl) from several sites around southeast Newfoundland. We aim to combine these new exposure ages, allowing direct dating of ice retreat, with any existing and available cosmogenic records to help temporally constrain the ice sheet reconstruction using this newly mapped landform record.
glacial geomorphology. Analysis of this record can be used to decipher the dynamics, extent, retreat patterns and configuration changes of the ice sheet throughout its evolution. Here we present new mapping based on our interpretation of SPOT satellite imagery and digital elevation models across Newfoundland as well as swath bathymetry from several locations offshore. Our new database consisting of ~150,000 individually mapped subglacial bedforms
which includes glacial lineations and ribbed moraines significantly increases the known landform record in this region. We illustrate how this data is being used to reconstruct this ice sheet using flowset analysis to separate discrete ice flow patterns into snapshots of ice sheet behaviour through time. Although this technique provides a relative chronology of ice sheet events, if we are to accurately explore former ice sheet variability and investigate links between
ice-sheet fluctuations established by this mapping programme greater radiometric control of ice-sheet events is required. To facilitate this we report forty new cosmogenic exposure ages (10Be and 36Cl) from several sites around southeast Newfoundland. We aim to combine these new exposure ages, allowing direct dating of ice retreat, with any existing and available cosmogenic records to help temporally constrain the ice sheet reconstruction using this newly mapped landform record.
| Original language | English |
|---|---|
| Pages | 65 |
| Number of pages | 1 |
| Publication status | Published (in print/issue) - 19 Aug 2015 |
| Event | Canadian Quaternary Association biennial meeting - Memorial University Newfoundland, St John's, Canada Duration: 16 Aug 2015 → 19 Aug 2015 https://canqua2015.wordpress.com/ |
Conference
| Conference | Canadian Quaternary Association biennial meeting |
|---|---|
| Abbreviated title | CANQUA |
| Country/Territory | Canada |
| City | St John's |
| Period | 16/08/15 → 19/08/15 |
| Internet address |
Keywords
- Newfoundland Ice Sheet
- remore sensing
- Subglacial bedforms
- glacial landforms
