4 ms·
> Statistically Cascadia is long overdue a 9 More precisely, it's 8, the average is 500 years, and the last one was in 1700.
by rootusrootus 3y ago
> Statistically Cascadia is long overdue a 9
More precisely, it's 8, the average is 500 years, and the last one was in 1700.
- DrBazza 3y agoCunningham's law eh? :)
- rootusrootus 3y agoHa! I had forgotten it had a name, but I guess that works. There is a fair bit of variability in the 500 year average, and 8 is still a seriously large earthquake, so preparations are definitely justified IMO.
- shkkmo 3y agoThat's not precisely accurate. The cascadian subductions zone uas produced magnitude 9 quakes in the past. The results I've seen (from a decade and a half ago) pegged the probability of a magnitude > 9 in the next 50 years at 1/10 and a magnitude > 8 at 1/3. The 500 years average is if you look at the last 7 events. 7 is a horribly low sample size and if you extend the timescale, that average drops by half and indicates we are past the 250 year average.