I was surprised, to say the least, to read about a strong earthquake tonight close to the Cayman Islands (20 miles southeast of Georgetown, the capital). Actually, there are a number of surprises for me here and I might as well run them down.
Though I knew there are plates upon which all of the Earth’s surface floats, I didn’t realize there was a boundary between two plates in the Caribbean. They grind against each other slowly, but constantly. The relative motion is only 6/10″ per year.
Of course one year is nothing to the Earth. Over 20 years that’s around a foot of motion. Over decades and centuries… well, you get the idea.
At some point something’s gotta give… and it did tonight. The quake was magnitude 6.7¹. That’s enough to be very scary and even more destructive. I have not yet heard any damage reports from the Caymans. Magnitude alone is not enough to predict destruction.
My second surprise was seeing actual ‘shock reports‘ from the Cayman Islands. This is actually an interesting idea from the United States Geological Service. They ask people to check in and rate the quake! It’s like Dick Clark on American Bandstand circa 1965.
As I type this there are 189 reports from the Caymans and one from Haiti. Each locale is averaged to show how the quake was felt.
I think the USGS does an amazing job keeping up with earthquakes. Their website is fast and thorough. I’m a math and science guy, so it appeals to me more than most. Still, if you’re curious, it’s worth looking at.
And, to get my own little plug in, there’s a link to the most recent large earthquake in the column on the right: Latest Large Earthquakes Worldwide.
¹ – Remember Richter? The Richter scale is no longer in use by geologists.
(12-14) 20:35 EST GEORGETOWN, Cayman Islands (AP) —
A strong earthquake struck the Cayman Islands on Tuesday — the strongest since 1900 — rattling windows and sending residents fleeing into the streets. No serious damage or injuries were reported.
The epicenter of the magnitude 6.7 earthquake was 20 miles south-southeast of Georgetown, said Kathleen Gohn, a spokeswoman for the U.S. Geological Survey based in Golden, Colo.
The initial quake lasted about 10 seconds and small shock waves were felt for more than 30 minutes, residents said.
“I got out of my house as fast as I could. I thought a plane was coming at us,” said Maxine Drake from Halifax, Nova Scotia, who lives part time in Grand Cayman.
It was the strongest tremor to hit the Cayman Islands since 1900, Gohn said. It also was one of several to strike the region in the last month.
Gohn said the tremors were unrelated but activity in the Caribbean has been high.
A tremor with a magnitude of 5.7 jolted the British Virgin Islands, the U.S. Virgin Islands and Puerto Rico on Saturday. No injuries were reported and there was little damage.
Another earthquake with a magnitude of 5.4, however, caused at least 90 aftershocks on Dec. 3 in Trinidad, leaving at least one woman dead and damaging several buildings and houses.
Last month, a magnitude 6.3 earthquake on the Caribbean island of Dominica caused an estimated $20 million in damages.
The Cayman Islands has been plagued with disaster this year, recently estimating hurricane damage caused by Hurricane Ivan at more than $3 billion.
The storm tore through the wealthy British territory in September, destroying 70 percent of buildings and damaging many hotels. Many residents were forced to move to Grand Cayman’s sister islands — Little Cayman and Cayman Brac — which received little damage.