The north quarry wall was the site of a number of important geological discoveries which provided information on the glacial history of southern Ontario. This area, referred to as the Toronto Brickyard, was designated as an earth science Area of Natural and Scientific Interest (ANSI) by the Ontario Ministry of Natural Resources in 2009 for exhibiting "Ordovician Georgian Bay Formation, Illinoian Glacial York Till, Sangamonian Interglacial Don Formation and Wisconsian Glacial Scarborough delta, Pottery Road sediments and Sunnybrook Till all overlain by North Bay Interstadial, Lake Iroquois sands."