Another earthquake was measured west of Vancouver Island on October 31st, just shy of a magnitude 5.0 on the Richter scale. Is it another earthquake related to the more powerful episodes back in October?
How many earthquakes do you think have occurred in British Columbia over the past month? 10? 20? 50? We’ve entered quite a tectonically active period.
When reviewing the data, over 80 earthquakes have been measured by sensitive seismometers, but only a couple have been felt. That’s the reality of the plate tectonics around British Columbia, with major plate boundaries being offshore.
The earthquake on the evening of October 31st is a distant cousin of the recent uptick in earthquake activity along a specific fault line, not associated with the Cascadia subduction zone. This was likely an aftershock on the series of greater than magnitude 6.0 earthquakes located on the Sovanco fault. This specific transform fault boundary moves by plates sliding in opposite directions. In this case, the motion is related to the movement of the Explorer and Pacific plates.
DO WE WORRY?
No. But, The ‘big one’ may happen 5 minutes from now, 5 years, or it could be well over 100 years away. From a preparedness standpoint, expecting the earthquake sooner, rather than later will ensure we’re ready to act when the inevitable big shake occurs. A mega-thrust earthquake is one that features a disastrous magnitude 9.0 or greater energy release, but another likely scenario is a weaker, more shallow earthquake under Vancouver Island, or even the Lower Mainland.
For more please refer to the following link (which includes excellent video breakdowns of the tectonic plates movement):