The strait 's bathymetry is varied , with the Laurentian Channel creating a deep trench through its centre , and comparatively shallow coastal waters closer to Newfoundland and Cape Breton Island . These bathymetric conditions have been known by mariners to cause rogue waves . The steep slope of the Laurentian Channel was the site of a disastrous submarine landslide at the southeastern end of the strait , triggered by the 1929 Grand Banks earthquake and leading to a tsunami that devastated communities along Newfoundland 's south coast and parts of Cape Breton Island
1929 Grand Banks earthquake
1929 Grand Banks earthquake
Cabot Strait