Midterm #1-Chapter 4 Flashcards
Canada experiences how many EQ’s per year?
3000
why is it hard to estimate the return period of EQ’s in Canada?
because our historical records don’t go far back in time, which makes estimating the return period challenging (our records only go back 200 years)
earliest EQ recorded in Canada:
1663 Charlevoix, QB
seismicity
frequency and spatial distribution of EQs
the most seismically active region in Canada is the…
West
top two cities with highest seismic risk in Canada
Vancouver, then Montreal
accelerographs
instruments that record the acceleration of the ground during an EQ
example of long term mitigation effort against seismic risk
National Building Code of Canada
seismic zonation
process of mapping foundation materials and their damage potential for future EQ’s
Where was the Haida Gwaii EQ located?
Queen Charlotte Islands, BC
Which 3 plates are currently subducting under Vancouver Island and NW US (under the North American Plate)? (at a rate of 4cm/ year)
Juan de Fuca, Gorda plate, and explorer plate
which fault is currently locked?
the Cascadia mega-thrust fault
what will happen when the Cascadia mega-thrust eventually ruptures?
an EQ of a magnitude 9 or greater will be triggered, and a possible tsunami
what is the return period of mega-thrust EQs?
600 years
intraplate EQ’s
EQ’s occurring within a tectonic plate, far away from plate boundaries
