Some residents in the Montreal region were jolted awake early this morning by a small earthquake.

Earthquakes Canada says the 3.3 magnitude quake struck at 3:22 a.m. The epicentre was located about nine kilometres northeast of downtown Montreal.

"It did occur right under the island of Montreal, toward the east end of the island," Nick Ackerley, a seismologist with Natural Resources Canada told CBC's Daybreak. "It was widely felt."

Many people took to social media, saying it felt like a small, brief explosion.

Watch as McGill University geologist, Yajing Liu, explains Montreal earthquakes:

A magnitude 3.3 earthquake was registered in the Montreal area on March 6. A geologist answers burning questions on the natural phenomenon. 2:00

It's not uncommon for small earthquakes to be loud, especially when they're that close, Ackerley explained.

"There's two things that are happening. One is that the seismic waves travel from the rupture underground toward you," he said.

When those waves hit the surface, they turn into sound, he said. That would explain why so many people reported hearing a loud noise. Shaking is usually the symptom of a larger earthquake that's more likely to cause damage.

"We have a lot of magnitude-three earthquakes in Canada, every year, all the time," he said.

"The thing that's a little bit unusual is for it to happen right under an urban area, so that lots of people feel it."

If you felt the earthquake, you can report the intensity in your area to Earthquakes Canada here.