Groundwater prospects in the Oak Ridges Moraine area, southern Ontario: application of regional geological models

Abstract

A geological model is presented for the glacial deposits of the Oak Ridges Moraine area of southern Ontario. The model contains four units as well as incised channels dissecting the strata. Channels eroded through the Newmarket Till, a regional aquitard, provide hydraulic connection between the aquifers of the overlying Oak Ridges Moraine and those of the underlying lower drift. Buried channels filled with silt, sand, and gravel, and preferentially oriented north-northeast-southsouthwest, are indicated by drill core and seismic reflection profiles. The model, with two successful case studies, has significant implications for groundwater resource development in the Greater Toronto Area. Groundwater flow to the lower drift may occur through channels so that groundwater resources in the lower drift may be more productive than previously suggested. Gravel sequences within channels may be targets for high yield wells. Further investigations are required to examine buried channel locations, distribution, and sediment fill.

Stratigraphic Architecture and Sediment Facies of the Western Oak Ridges Moraine, Humber River Watershed, Southern Ontario*

“…The absence of well defined channels south of the ORM, and further south within Lake Ontario is additional support for the occurrence of a subglacial lake in the lake Ontario basin (cf. Sharpe et al, 1996;Kenny, 1998).…”

Subsurface heterogeneity in the geological and hydraulic properties of the hummocky Paris Moraine, Guelph, Ontario

“…As positive relief features in the landscape, these moraines are often considered important zones for recharge, and some host complex and stratified aquifers that are an important source for nearby urban centres (Sharpe et al 1996Howard et al 1997;Bajc and Shirota 2007;Bajc et al 2014). While several interlobate stratified moraine complexes in southern Ontario have been the focus of comprehensive geological and hydrogeological studies (Barnett et al 1998;Sharpe et al 2004;Bajc et al 2014), end and recessional moraines have generally not received the same attention from the international scientific community (Andersson 1998;Gartner Lee Ltd. 2004;Blackport Hydrogeology Inc. et al 2009;Russell et al 2009Russell et al , 2013.…”

Wisconsinan Inter-Lobal Stratigraphy in Three Quarries Near Woodstock, Ontario

“…The Oak Ridges moraine, formed between the Simcoe and Ontario lobes in the northern Greater Toronto Area, became a major mapping, drilling, and geophysics project to define the geometry and spatial relationships of aquifers and aquitards (Sharpe et al, 1996;Barnett et al, 1998) (Fig. 1).…”