Earthquakes Canada is reporting a substantial tremor in the Labrador Sea.

The quake, which registered 4.7 on the Richter scale, struck around 1:00 p.m. Labrador time yesterday. The quake was about 18 km under the surface, approximately midway between the north coast of Labrador and Greenland, and was not felt on land.

It’s one of a number of quakes reported off the coast of Labrador in the last year or so.

Dr. Allison Malcom, a seismologist and associate professor of geophysics at Memorial University, says while earthquakes in the region are not common, they can still get some good estimates on where they occur.

She says there are not as many instruments on the east coast of Canada because earthquakes there are not as frequent as on the west coast, but a quake the size of a magnitude four can result in great estimates on its size and depth from the worldwide seismological network.

The reasons behind earthquakes like those off Labrador are less well understood because they are so infrequent.

In the meantime, a magnitude two earthquake registered near Stephenville in the last month, but Malcolm says it likely wasn’t noticed.