Written by John Vidale, a professor at the University of Washington, directs the Pacific Northwest Seismic Network and is the Washington state seismologist.
From The Washington Post:
Five myths about the Pacific Rim
A tragic month along the tectonic subduction zones that surround the Pacific Rim has also been a spellbinding one for seismologists. A magnitude 6.2 quake on April 14 was followed a day later by a magnitude 7.0, together killing at least 49 in the Kyushu region of Japan. Less than 24 hours later, a magnitude 7.8 in Ecuador killed at least 650. Major deep earthquakes in Burma and Afghanistan in April were also deadly, and a series of quakes this month struck Vanuatu, too. So many earthquakes of at least magnitude 6.5 in a week is quite uncommon, even in the volatile tectonic zone known as the Ring of Fire, which encircles the Pacific Ocean. But the dangers of this region remain widely misunderstood, and myths — the notion that animals can predict earthquakes, for instance, or that the government knows they’re coming but hides the information — stubbornly persist.
1. Giant faults such as the San Andreas dominate the danger.
World-destroying films such as “San Andreas” and “Earthquake” feature magnitude 8s and 9s. NBC even produced a miniseries called “10.5: Apocalypse,” about a quake that splits North America into two islands. “The Really Big One,” the New Yorker story for which Kathryn Schulz won a Pulitzer Prize this year, explained the potential dangers of living near the large Cascadia fault in the Pacific Northwest. And the plate collision zones under South America and Alaska’s Aleutian Islands are famous for the monster quakes they spawned in the 1960s: magnitude 9.5 in Chile and magnitude 9.2 in Alaska.
But the bigger threats come from smaller quakes. Some are along the major faults, but even more are from the small faults right underfoot. Only one earthquake larger than magnitude 8.0 is on the list of the 16 deadliest earthquakes; about one-third had magnitudes of less than 7.5. Each year, on average, there are one or two quakes bigger than magnitude 8; 15 bigger than 7; about 150 bigger than 6; and so on.
Christchurch, New Zealand, had to be essentially rebuilt after a direct hit from a mere 6.3 in 2011. Japan was shocked when a magnitude 6.9 decimated Kobe in 1995. And the costliest U.S. earthquake was the magnitude 6.7 Northridge quake that shook Southern California in 1994.
Four more items at the page - excellent clearly-written article.
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