Accurately reconstructing the history of paleo-ice sheets is critical for understanding climate and ice sheet dynamics which is important if we are to better understand the future trajectory of the Greenland and Antarctic Ice Sheets in a warming world. Ice sheets have long life cycles and the best way of understanding their response to climate change is to investigate the geological record of paleo-ice sheets which provides a record of former ice sheet behaviour through full glacial cycles. The former British-Irish Ice Sheet (BIIS) is known to have been sensitive to climatic signals from the North Atlantic making it a good proxy for examining these long-term climate/ice sheet relationships. During the Last Glacial Maximum in Ireland (~27 ka), the BIIS covered all of Ireland, extended to the continental shelf edge and then retreated to a coastal position as an ice dome by ~21ka in the North. After ~18 ka it is thought to have retreated into the Donegal Mountains and down-wasted to lower altitudes during its final stages. However, to date the full retreat pattern has not been mapped and new dates are required to fully age constrain the final deglaciation in this region. This PhD project addresses these issues through geomorphological mapping and dating using Schmidt Hammer Exposure Dating (SHED), a technique which has been shown to accurately constrain the timing of BIIS deglaciation in granite lithologies (Fig 1). This will be achieved by: 1) The identification and mapping of deglacial geomorphological features using high-resolution aerial imagery. 2) Dating of these features to reconstruct the deglacial chronology of the Donegal Ice Dome. 3) Using both datasets to develop an age-constrained conceptual model of the final deglacial chronology of the Donegal Ice Dome constraining down-wasting and retreat. This poster presents results from 30 sites that have been dated using SHED across the Derryveigh Mountains in northwest Donegal (Fig. 2) providing deglacial ages ranging from 19.58 ka to 11.85 ka. This research will further our understanding on the pattern and timing of deglaciation of this significant ice source and provides a framework investigating the drivers glacial change in this region.
|Publication status||Published - 24 Jul 2019|
|Event||20th Congress of the International Union for Quaternary Research - The Convention Centre, Dublin, Ireland|
Duration: 24 Jul 2019 → 31 Jul 2019
|Conference||20th Congress of the International Union for Quaternary Research|
|Period||24/07/19 → 31/07/19|
- Ice Sheet