Three earthquakes with magnitudes larger than M6.0 (M6.6, M6.8 and M6.5) hit off Vancouver, Canada, near the Cascadia Subduction Zone… And that in only 40 minutes! Although very shallow there is no tsunami risk.
The series of strong quakes started at 5.39am UTC (10.39pm local time) with a M6.6 quake 218km SW of Port Hardy, Canada and reported by at least 40 people on the USGS homepage.
This first shallow shaking was followed, 30 minutes later, by a stronger M6.8 tremor almost at the same spot, 197km SW of Port Hardy, Canada. Shakings were reported by at least 75 people on the USGS homepage.
Finally, the third strong tremor, a M6.5, hit at 6:22am UTC (11.36pm PDT), 223km SW of Port Hardy, Canada.
The 3 quakes are likely due to horizontal strike-slip faulting on the Sovanco transform fault that offsets the Juan de Fuca Ridge.
The quake was not in the Cascadia subduction zone and did not trigger any tsunami warnings.
Tsunami Info Stmt: M6.8 130mi SW Port Alice, British Columbia 2317PDT Oct 21: Tsunami NOT expected; CA,OR,WA,BC,and AK
— NWS Tsunami Alerts (@NWS_NTWC) October 22, 2018
These three strong quakes are just a warning of the next big one along the Cascadia Subduction Zone. Get prepared and be ready!