Lake Temiskaming

Lake Temiskaming is a crack in the continent that never finished opening. It runs 110 kilometres and is in places only a few hundred metres wide.

The lake sits in the Timiskaming Graben, a rift valley that began pulling apart when the Iapetus Ocean opened and then stopped. The crust dropped between two fault lines and stayed down. That is why the shape reads so differently from a glacial lake: long, straight and narrow, following a fault rather than the path of ice.

It is also genuinely deep. The surface sits about 178 metres above sea level and the bottom reaches 216 metres down, which puts the floor of the lake below sea level. The Algonquin name says the same thing. Temikami comes from tim, deep, and kami, open water.

The rift has not gone quiet. This is one of the more seismically active corners of eastern Canada, and a substantial earthquake struck here in 1935.