May 10, 2011 09:46 GMT  ·  By

South America's Andes mountains are subjected to a very high risk of experiencing a massive earthquake, experts say. The magnitude of the tremor would make it about 10 times stronger than any other similar event that took place in the same area ever before.

The tremor risk should be shared with the millions of people living on and near the Andes mountain range, and who would be subjected directly to the effects of such a seismic event, where it to occur.

In a new study, experts took a closer look at an area located along the eastern flank of the Andes Mountains, where about 2 million people live. Called the Subandean maring, this location was originally thought capable of producing only a magnitude 7.5 earthquake.

But the investigation revealed that the margin could spawn tremors as intense as magnitude 8.9, which would be disastrous for the surrounding areas. Only an insignificant percentage of the buildings that would be affected by the tremor can withstand such a powerful event.

“If the entire fault below the Subandes were to rupture, you can get a lot of damage. It could be like a combination of the 2010 earthquake in Chile, which was very powerful, with the 2010 earthquake in Haiti, which hit a place with inadequate building standards,” says Benjamin Brooks.

The investigator, who holds an appointment as a researcher and a geodesist at the University of Hawaii in Honolulu, was part of a team that used Global Positioning System (GPS) data to conduct the investigation, Our Amazing Planet reports.

He and his team looked at how the Earth's surface moved around the Subandean margin over a period of time, and determined that the eastern segment of the margin may be locked in place. This was determined from satellite measurements of how much it moves annually.

The east-to-west segment of the plate moves 2 to 10 millimeters less per year than the rest of the margin, suggesting that it is blocked in place. This means that tension is now accumulating under the Nazca tectonic plate.

This plate grinds slowly against the South American plate, and the interactions between the two can produce earthquakes with magnitudes between 8.7 and 8.9, experts say.

“The city of Santa Cruz in Bolivia is at the central portion of this area, a major economic center. The oil industry is located there, as is a lot of farming. The shaking from a major earthquake in this area could also affect northern Argentina,” Brooks explains.

More details about the new investigation and the interactions developing between the two major plates are available in a paper published in the May 8 online issue of the top journal Nature Geoscience.