Thousands were rattled awake early Monday morning when a 4.1 magnitude earthquake struck between Victoria and Vancouver, according to Earthquakes Canada.

Sidney is 42 kilometres west of the epicentre. Victoria is 43 km from the epicentre with Vancouver being 73 km away.

Earthquakes Canada says the earthquake, which took place at 5:02 a.m., was “lightly felt” around Victoria and Vancouver.

Earthquakes Canada initially reported the magnitude as 4.8, then updated it to 4.1 around 6 a.m.

John Cassidy, seismologist with Earthquakes Canada, says this earthquake woke many thousands of people on the Island and the Vancouver region.

“Myself included,” he said. “It was very, very clear it was an earthquake this morning, lots of rumbling, lots of shaking for about 10 seconds.”

Cassidy says 10 seconds of shaking is a longer period than we’ve seen for “quite some time” in Victoria.

“We’ve had a few felt earthquakes in recent weeks, but to have five or 10 seconds of very distinct shanking, we probably have to go back nearly 20 years to the Nisqually earthquake, which was a much larger, farther away earthquake. It was a 6.8 near Seattle.”

The Nisqually earthquake took place at 10:54 a.m. on Feb. 28, 2001, and shaking occurred for about 30-40 seconds, according to the Washington Military Department.

Cassidy says there could be some aftershocks from this earthquake, and typically from an earthquake of this magnitude aftershocks would be in the magnitude three range.

The United States Geological Survey is reporting the magnitude of the earthquake at 4.5. Differences in magnitudes from different agencies is common, according to the USGS.

“Magnitude estimates for a given earthquake can vary between reporting agencies due to differences in methodology, data availability, and inherent uncertainties in seismic data,” USGS says in an information page on its website.

“Even for well-recorded events, differences in magnitude of 0.2 or 0.3 units are common and representative of the inherent uncertainty of the magnitude estimation process.”

The U.S. National Tsunami Warning Center says there is no tsunami risk from the earthquake. The agency says it has not received reports of damage.