Scientists have found that earthquakes can permanently crack the Earth and have caused the crust in northern Chile to crack permanently, according to Yahoo! News.
Structural geologist Richard Allmendinger, who works at Cornell University, discovered this while doing research on the Iquique Gap with graduate students.
"My graduate students and I originally went to northern Chile to study other features," Allmendinger said. "While we were there, our Chilean colleague, Professor Gabriel Gonzalez of the Universidad Catolica del Norte [North Catholic University], took us to a region where these cracks were particularly well-exposed."
"I still remember feeling blown away," Allmendinger told OurAmazingPlanet. "What were these features and how did they form?
"Scientists hate leaving things like this unexplained, so it kept bouncing around in my mind," he continued.
Previously, the Earth was thought to rebound after large earthquakes, with the crust springing back to its initial location after a period of months or decades.
In northern Chile, which is the driest place on Earth, there is a unique geological record of earthquakes going back a million years. The record of the large number of earthquakes available in the rocks allowed the researchers to determine their average behavior over a much longer period of time than previously studied, allowing them to pick out patterns.
"It is only in a place like the Atacama Desert that these cracks can be observed, in all other places, surface processes erase them within days or weeks of their formation, but in the Atacama, they are preserved for millions of years," Allmendinger said. "We have every reason to believe that our results would be applicable to other areas, but it is simply not preserved for study the way that it is in the Atacama Desert."
The researchers work "calls into question the details of models that geophysicists who study the earthquake cycle use," Allmendginer said. "Their models generally assume that all of the upper-plate deformation related to the earthquake cycle is elastic, recoverable, like an elastic band, and not permanent."
If the deformation is permanent, more complicated models will have to be used, according to Allmendinger.
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