Cascadia fault line identified as potential hot spot for ‘mega quake’

North America’s west coast, along the Cascadia fault line, is one of the Top 5 areas in the world most vulnerable to mega-earthquakes, according to Aon Benfield.
The mega-earthquakes are moment magnitude(Mw) 8+, according to Aon Benfield’s report, When The Earth Moves: Mega-Earthquakes To Come?
The five most vulnerable regions, according to the research, are:
1. Caribbean (Lesser Antilles) – The 2cm a year rate of plate convergence is enough to produce a mega-earthquake of Mw 9 once every 3000 years.
A major loss in the Caribbean would quickly use up available reinsurance capacity, according to Aon Benfield.
2. Chile – As the only segment of the Chile-Peru Subduction Zone not to have ruptured within the last 100 years, the north Chile segment is now considered to be a region at high risk from an earthquake similar in size to the 2010 event. Reinsurance programs are renewing with increases of 75% or more, following the February quake.
3. Indonesia (Sumatra) – Padang is now regarded as being at high risk, with a magnitude of 8.5 or more. A mega-earthquake would undoubtedly increase the price of reinsurance following a sizeable insured loss.
4. Japan – The South Japan Subduction Zone has a complex pattern of three segments. The largest earthquakes rupturing along the whole subduction zone may have magnitudes up to 8.6.
A mega-earthquake in this region would most likely be a market-moving event.
5. North America (Cascadia) – The last mega-earthquake on this subduction zone occurred 300 years ago.
While the short to medium term probability of a mega-earthquake may be low, insurers should not disregard the associated risks to the cities along the coast, Aon Benfield warned.