2015 GSA Annual Meeting in Baltimore, Maryland, USA (1-4 November 2015)

Paper No. 56-11
Presentation Time: 4:15 PM

QUANTIFYING ERODED SEDIMENT VOLUME DURING DRUMLIN FORMATION IN SIMCOE COUNTY


MALONEY, Katie M., School of Geography and Earth Sciences, McMaster Univerity, 1280 Main Street West, Hamilton, ON L8S4K1, Canada, INGRAM, Rebekah C., School of Geography and Earth Sciences, McMaster University, 1280 Main Street West, Hamilton, ON L8S4K1, Canada, MACLACHLAN, John C., School of Geography and Earth Sciences, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada and LEE, Rebecca E., School of Geography and Earth Sciences, McMaster University, 1280 Main St. West, Hamilton, ON L8S 4L8, Canada, malonekm@mcmaster.ca

Drumlins, despite being well studied, are still incredibly enigmatic in terms of their formation processes. As a result of the extreme complexity and variability that has been observed in drumlin forms and internal composition, several theories have been presented to explain their origin. The current understanding focuses on drumlin creation by depositional and erosional processes associated with large subglacial meltwater floods, large-scale deformation of subglacial sediments and instability at the ice-bed contact. These theories necessitate the removal and transport of sediment, either in a single depositional event (subglacial meltwater flood theory) or episodically (deforming-bed theory and instability theory). To support an erosional theory for the formation of drumlins, large volumes of sediment would have undergone transport and deposition. The volume of sediment that would have eroded from part of the Peterborough Drumlin Field in Simcoe County was calculated using two methods in a Geographic Information System. The limitations of both methods and the geological composition of potential sediment sinks were analysed. The range of eroded sediment volume was calculated to be 3.5–8.3 km3, which could fill between 30.2% and 71.6% of the Lake Simcoe basin. The high volume of sediment that was estimated in this study will have future implications in the drumlin debate and for the feasibility of an erosional process of formation.

The results of this research have been published:

Englert, R., Ingram, R., Madronich, L., Maloney, K., Moor, K., Rooney, K., and Mulligan, R. 2015. Quantifying Eroded Sediment Volume during Drumlin Formation in Simcoe County. Cartographica, 50(3) pg.172-178