By Jonathan Erdman, www.weather.com
A massive, powerful earthquake shook Chile early Saturday morning. Here is some quick perspective on how strong and how frequent these giant earthquakes are.
CHILE’S IN THE “RING OF FIRE”
Unfortunately, destructive earthquakes are nothing new to western South America, and to Chile in particular.
Chile lies squarely on the eastern periphery of the “Ring of Fire”, namely, a zone surrounding the Pacific Ocean, where 90% of the world’s earthquakes occur.
Since 1900, there have been only four stronger earthquakes measured worldwide. Yes, Chile holds the world record for the strongest quake, a magnitude 9.5 monster in May 1960. This quake’s epicenter was not far from Saturday’s tremor. Roughly 1600 were killed and 2 million were homeless.
HOW DESTRUCTIVE CAN THIS BE?
According to The Weather Channel’s Dr. Steve Lyons, an earthquake’s magnitude is merely a scientific measure of the energy released during the quake. The magnitude is not directly tied to local damage.
Lyons says it’s the “shaking intensity” that controls damage potential. Sharp accelerations of the ground typically causes the most damage. This is precisely what occurred in Haiti in January. Building type also controls how much damage occurs. Modern buildings built to earthquake codes would fare better.
That said, as indicated in the graphic below, magnitude 8.0 and stronger quakes can cause total destruction near the epicenter!
Aftershocks can also be dangerous, in that they may cause weakened structures to fail, can make ongoing search and rescue operations hazardous, can trigger landslides, and lead to public panic.
WAS THIS QUAKE REALLY FELT IN NEW ORLEANS?
Well…not the quake itself.
However, the quake actually caused Lake Pontchartrain to “slosh”, roughly 13cms higher than predicted tide levels on the west end of the lake 11 minutes after the quake was recorded in Chile. Lake Pontchartrain is roughly 7500 kms away from the Chilean quake’s epicenter.
These standing waves are called “seiches” (pronounced “sayshs”). They can commonly occur far from an earthquake, in enclosed bodies of water as small as your backyard swimming pool.
In fact, swimming pools in Puerto Rico overflowed from the Great Alaska Earthquake of 1964!