With disasters striking Haiti, Chile and most recently Turkey, it seems like there is no end in sight for the earthquake-weary.
New evidence released from Ohio State University (OSU) shows that the 8.8-magnitude mega-quake that struck off the coast of Chile last month was so powerful that multiple South American cities were picked up and physically moved from their original locations.
The effects of the temblor that struck Concepcion, Chile, were felt as far away as Brazil and the Falkland Islands in what is believed to be the fifth largest quake ever recorded.
Here's the break down of the shake-up:
- Conception, Chile, shifted 10 feet to the west.
- Santiago, Chile’s capital, was displaced about 11 inches to the west-southwest.
- Buenos Aires, the capital of Argentina, moved about 1 inch to the west.
The cities of Valparaiso and Mendoza, Argentina, northeast of Concepcion, also showed significant movement.
Image shows a map of the preliminary recorded movement readings of city displacement caused by the 8.8-magnitude quake, based on the team's GPS measurements. Map produced by James Foster and Ben Brooks.
So how do you measure how an entire city moves?
Researchers from four universities and several agencies -- including geophysicists on the ground in Chile -- gathered readings at 25 GPS locator stations set up prior to the major quake and then compared them to readings taken 10 days later to come up with their preliminary numbers.
The measuring project is called Project CAP: Central and Southern Andes GPS Project.
Ben Brooks, an associate researcher with the School of Ocean and Earth Science and Technology at the University of Hawaii and co-principal investigator on the project, worked with a team of researchers from OSU, University of Memphis and several others to analyze the data.
"The GPS stations are located on stable monuments at various places in Chile, Argentina, and surrounding countries," Brooks told Discovery News in an email. "Each place is different but the OSU/UHawaii/Memphis group always tries to place its monuments in rock or very deeply anchored tripods to insure we are measuring crustal movement and not just local displacements."
"The fact that there is so much consistency in the preliminary GPS solution that we have presented (meaning there is not wild variation between neighboring points) means that our results are valid for large regions," Brooks explained. "So a region as large as a city moved three meters (9.8 feet) to the west, but neighboring regions did so by almost as much."
The California Institute of Technology is also participating in the project, as well as the Instituto Geografica Militar, the Universidad de Concepcion and the Centro de Estudios Cientificos, all in Chile, according to OSU's press release.
In Argentina, the Instituto Geografica Militar, the Universidad Nacional de Cuyo in Mendoza and the Universidad Nacional de Buenos Aires are collaborating in the work. UNAVCO, a consortium of more than 50 institutions and agencies involved in research in the geosciences, is providing equipment for the project, the OSU press release said.
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