These screen captures clearly show how this part of the Ring of Fire, where several tectonic plates are constantly under stress, is very prone to earthquakes. Although there were no immediate reports of death or injury there was a M5.0 aftershock, adding to the more than 150 M5.0s and above that have occurred throughout the world in just the past 30 days or so.
Centered in the above Google Earth image is the location of a 7.1 magnitude earthquake that hit a remote part of eastern Indonesia on Saturday, April 6 2013.
They are all occurring in increasing numbers around the Ring of Fire where tectonic plates are acting like zippers coming undone.
Even more telling, using the USGS database we can search for earthquakes M6.0 and above in the past 12 months, and we find there have been 134 that meet the search criteria, as shown at right.
Thirteen of those were M7.0 or more, which is well above the historical 12-month average for quakes of such magnitude.
Most people will remain
unaware of these statistics,
and unprepared for even
bigger ones with associated
tsunamis, and the likelihood that a combination of earthquakes and tsunamis will wreak havoc with ocean-side nuclear plants, as happened in Japan in 2011.
Obviously the smaller countries such as New Zealand, Indonesia, Japan etc which are divided by or surrounded by fault lines and ocean trenches are the most vulnerable, while coastal cities are also very much in the danger zone.
People quickly forget when the last big earthquake occurred, if it was somewhere else in the world, and because scientists tell us that the major earthquakes are statistically hundreds if not thousands of years apart, it’s natural to believe there’s only a small chance that we’ll ever have such an experience.
However, if you imagine geologic time as a clock on which one hour represents a thousand years, one minute is a hundred, and one second is a day, you get a better idea of
how “soon” to expect The Biggie. We could also liken this latest 12-month data to the ticking down of an alarm clock to wake-up time, except it would be stupid to wait till then to open our eyes because this is an alarm clock that no-one can turn off.
More importantly, it’s not just the Biggies we should consider. If you drip water onto stone, it will eventually wear it away, and in that sense, even the small earthquakes, especially when they occur in swarms, are doing their bit to unsettle both the tectonic plates and fault lines, as well as volcanoes, of which there are thousands around the Ring of Fire.
In the western United States alone lies the Cascade Volcanic Arc. It includes nearly 20 major volcanoes, among a total of over 4,000 separate volcanic vents. And just offshore is the Cascadia subduction zone, which is overdue for releasing a M9.0+ quake and tsunami. So what does all that tell us about what has happened over the millennia, and what to expect and prepare for?
Michael Knight is an independent writer who began an international career in all media in 1960. He now owns The Portland Preparedness Center in Portland Oregon. twitter: @JournoMichael
This work by Michael Knight is licensed under a Creative Commons Attribution-NoDerivs 3.0 Unported License.[/box]