The Ottawa-Bonnechere Graben is a geological structure that coincides with a 55 km (34 mi) wide topographic depression extending from near Montréal through Ottawa. It is part of the Saint Lawrence rift system that also includes the seismically active Saguenay graben. This rift valley was formed when the Earth's crust moved downward about a kilometre between two major fault zones known as the Mattawa and Petawawa faults.

Lake Nipissing is a lake in the Canadian province of Ontario. It has a surface area of 873.3 km2 (337.2 sq mi), a mean elevation of 196 m (643 ft) above sea level, and is located between the Ottawa River and Georgian Bay. Lake Nipissing is the third-largest lake entirely in Ontario. It is relatively shallow for a large lake, with an average depth of only 4.5 m (15 ft). The shallowness of the lake makes for many sandbars along the lake's irregular shoreline. The lake reaches a maximum depth of 64 m (210 ft) near the mouth of the French River, off the shore of Blueberry Island. The lake has many islands most of which are protected under the Protection of Significant Wetlands scheme, controlled by the Ministry of Natural Resources and Forestry.