A powerful earthquake in the ocean just south of Port Hardy jolted northern Vancouver Island and is sending shock waves across the province as residents assess their readiness for "the big one."

The Geological Survey of Canada says the 6.6 quake hit just after 8 last night and was followed by two aftershocks with magnitudes of 4.2 and 5.

No significant damage occurred, and no tsunami was generated, but reports of swaying buildings and jumping furniture flooded in from the Island and across Metro Vancouver.

The city of Vancouver issued a release shortly after the quake, saying the shaker is a reminder to make or update an emergency kit and be prepared to survive for several days without water, food or shelter.