North of the moraine drumlins form a large field centred on Peterborough that is comprised of streamlined landforms of km scale length and several hundred metres width. The dominant drumlin orientation is north-northeast. The drumlins are predominately spindle shaped in the north and centre of the area (1); where as, south of Rice Lake they are more oval (2). Drumlins form subglacially and by processes that are poorly understood. Mechanisms invoked to explain drumlin formation include, substratum deformation, meltwater sediment deposition within cavities, and meltwater erosion.

Further Reading

Menzies, J. 1989: Toward a general hypothesis on the formation of drumlins. in Menzies J. and Rose, J. (eds.), Drumlin Symposium. Balkema, Rotterdam, pp.9-24.

Boyce, J.I. and Eyles, N. 1991: Drumlins carved by deforming till streams below the Laurentide Ice Sheet; Geology, 19, 787-790.

Chapman, L.J. and Putnam, D.F. 1966: The Physiography of Southern Ontario, 2nd edition; University of Toronto Press, 386 p.

Shaw, J. 1996: A meltwater model for Laurentide subglacial landscapes: in McCann, S.B. and Ford, D.C. (eds.), Geomorphology Sans Frontieres; Wiley & Sons Ltd., chapter 7, pp. 181-236

Shaw, J. and Sharpe, D.R. 1987: Drumlin formation by subglacial meltwater erosion: Canadian Journal of Earth Science, 24, 2316-2322.