Giant waves in Canada

Seismometer in St. John's shows how intense Thursday's winds were

The waves crashing into the rugged shoreline of Newfoundland and Labrador this week led to waves of a different kind.

The squiggly black lines produced by a Natural Resources Canada seismometer show the seismic activity of a vicious windstorm that whipped across the province on Wednesday and Thursday.

The wind and waves were so strong, the island was shaking.

"What we saw over the past 48 hours was quite a dramatic change in [activity]," said John Cassidy, an earthquake seismologist with Natural Resources Canada.

"It was very noticeable and in our seismic data, our plots, it just jumped off the page. You could just see that shaking."

The federal government has seismometers - tools that measure earth movements - all across the country.

Cassidy said each year, a handful of storms will produce winds and waves strong enough to record seismic activity on the east and west coast.

With winds gusting between 100 and 140 km/h, the conditions were just right to get the Rock rocking.

"It's that combination of the wind, that incredible wind, and the waves that were hitting the island," Cassidy said.

"Both of those, the waves and the wind, gets trees shaking, rocks shaking ... And all of that can be recorded by our seismometers on the island."

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