But earthquakes are impossible to predict, and because scientists aren't even sure why major quakes occur away from plate boundaries, it is even more difficult to estimate a probability for New Madrid. Were another magnitude 8 earthquake to strike the region today, the toll would be much, much higher.īy analyzing deposits of sand that squirted out of the ground during past major quakes, Schweig and others estimate an average time between earthquakes of 500 years. The quake was felt over an area of two million square miles - nearly two-thirds of the country.ĭuring the quakes, the ground rose and fell, trees were bent, deep cracks opened up in the ground, large landslides swept down hills, huge waves washed boats out of the Mississippi River and river banks, islands and sand bars gave way.ĭamage was widespread, but only a few people died thanks to the sparse population in what was then the Louisiana Territory but today is near the junction of Missouri, Illinois, Kentucky, Tennessee and Arkansas. In 18, a swarm of at least three massive earthquakes struck near New Madrid, the largest of which exceeded a magnitude 8 and caused violent, damaging shaking in an area 10 times larger than did the 1906 earthquake. It created a tsunami that crossed the entire Pacific Ocean and caused damage along parts of the Japanese coast. The last monster quake that ruptured the entire length of the Cascadia fault occurred in 1700 and was around a magnitude 9.
Unfortunately, the fault may be due for another big one any day now. Cascadia is the same type of fault that caused the 2004 Sumatra quake and tsunami.įortunately, these mega quakes only come around once every few hundred years. On top of the danger from shaking, within minutes, a tsunami would likely inundate the low-lying coastal areas.
San andreas mega quake times magazine full#
The shaking could last a full four minutes, which would damage or bring down structures that could have survived a shorter duration. There could be thousands of deaths and unprecedented damage for a quake in this country. "There are lots of other earthquakes that may happen first, but they won't be as big," said marine geologist Chris Goldfinger of Oregon State University in Corvallis.Īn earthquake of this size would completely devastate the region, which includes Portland, Seattle and Vancouver.
0 kommentar(er)
