Email a Friend
Printer Friendly
Slashdot It!
Submit to Reddit
Add to Facebook

Researchers show how far South American cities moved in quake

March 09, 2010

COLUMBUS, Ohio - The massive magnitude 8.8 earthquake that struck the west coast of Chile last month moved the entire city of Concepcion at least 10 feet to the west, and shifted other parts of South America as far apart as the Falkland Islands and Fortaleza, Brazil.

These preliminary measurements, produced from data gathered by researchers from four universities and several agencies, including geophysicists on the ground in Chile, paint a much clearer picture of the power behind this temblor, believed to be the fifth-most-powerful since instruments have been available to measure seismic shifts.

Buenos Aires, the capital of Argentina and across the continent from the quake's epicenter, moved about 1 inch to the west. And Chile's capital, Santiago, moved about 11 inches to the west-southwest. The cities of Valparaiso and Mendoza, Argentina, northeast of Concepcion, also moved significantly.

The quake's epicenter was in a region of South America that's part of the so-called "ring of fire," an area of major seismic stresses which encircles the Pacific Ocean. All along this line, the tectonic plates on which the continents move press against each other at fault zones.

The February Chilean quake occurred where the Nazca tectonic plate was squeezed under, or "subducted," below the adjacent South American plate. Quakes routinely relieve pent-up geologic pressures in these convergence zones.

The research team deduced the cities' movement by comparing precise GPS (global positioning satellite) locations known prior to the major quake to those almost 10 days later. The US Geological Survey reported that there have been dozens of aftershocks, many exceeding magnitude 6.0 or greater, since the initial event February 27.

Mike Bevis, professor of earth sciences at Ohio State University, has led a project since 1993 that has been measuring crustal motion and deformation in the Central and Southern Andes. The effort, called the Central and Southern Andes GPS Project, or CAP, hopes to perhaps triple its current network of 25 GPS stations spread across the region.

"By reoccupying the existing GPS stations, CAP can determine the displacements, or 'jumps', that occurred during the earthquake," Bevis said. "By building new stations, the project can monitor the postseismic deformations that are expected to occur for many years, giving us new insights into the physics of the earthquake process."

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, said that the event, tragic as it was, offers a unique opportunity to better understand the seismic processes that control earthquakes.

"The Maule earthquake will arguably become one of the, if not the most important great earthquake yet studied. We now have modern, precise instruments to evaluate this event, and because the site abuts a continent, we will be able to obtain dense spatial sampling of the changes it caused.

"As such the event represents an unprecedented opportunity for the earth science community if certain observations are made with quickly and comprehensively," Brooks said.

Working with Bevis and Brooks on the project are Bob Smalley, the University of Memphis, who is leading field operations in Argentina; Dana Caccamise at Ohio State, who is lead engineer, and Eric Kendrick, also from Ohio State, who is with Bevis now in Chile making measurements in the field.

Along with Ohio State University and the University of Hawaii, scientists from the University of Memphis and the California Institute of Technology are participating in the project. Additionally the Instituto Geografica Militar, the Universidad de Concepcion and the Centro de Estudios Cientificos, all in Chile, also were partners.

In Argentina. the Instituto Geografica Militar, the Universidad Nacional de Cuyo in Mendoza and the Unversidad 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 researchers have constructed a map showing the relative movement of locations after the Maule, Chile earthquake. Images showing that map are available at http://researchnews.osu.edu/archive/chilequakemap.htm

The Ohio State University

Related Earthquake Current Events and Earthquake News Articles

Earthquake Current Events and Earthquake News RSS

New findings indicate sediment composition affected the strength of Sumatran earthquake
Sumatra experiences frequent seismic activity because it is located near the boundary of two of Earth's tectonic plates. Earthquakes occur at 'subduction zones,' such as the one west of Indonesia, when one tectonic plate is forced under another--or subducts.

Shocking results from diamond anvil cell experiments
At first, nanoshocks may seem like something to describe the millions of aftershocks of a large earthquake.

Tiny clays curb big earthquakes
California's San Andreas fault is notorious for repeatedly generating major earthquakes and for being on the brink of producing the next "big one" in a heavily populated area. But the famously violent fault also has quieter sections, where rocks easily slide against each other without giving rise to damaging quakes.

New areas prone to moderate earthquakes identified in Iberian Peninsula
Some areas of the Iberian Peninsula, where earthquakes of moderate magnitude have never yet been recorded, such as certain parts of the Cordillera Cantábrica mountain range, the far west of the Cordilleras Béticas mountains and the north of Valencia, could have the potential to generate such quakes, according to a study produced by Spanish, Russian and Italian scientists and published this month in the journal Rendiconti Lincei.

Like fireflies, earthquakes may fire in synchrony
In nature, random signals often fall mysteriously in step. Fireflies flashing sporadically in early evening soon flash together, and the same harmonic behavior can be seen in chirping crickets, firing neurons, swinging clock pendulums and now, it turns out, rupturing earthquake faults.

Aerogeophysical Survey Provides Promising Prospects of Economic Development in Afghanistan
Analyzing nearly 20 terabytes of data collected from 220 mission flight-hours covering more than half of Afghanistan, Naval Research Laboratory and the U.S. Geological Survey investigators reveal several potential major oil and gas sedimentary basins, mineral-rich regions, and hydrologic resources for agriculture and economic development as recently reported by Department of Defense.

110-foot concrete bridge withstands 8.0 earthquake simulation
After a succession of eight separate earthquake simulations, a 110-foot long, 200-ton concrete bridge model at the University of Nevada, Reno withstood a powerful jolting, three times the acceleration of the disastrous 1994 magnitude 6.9 Northridge, Calif. earthquake, and survived in good condition.

NJIT professor tells architects building practices to withstand hurricanes
Rima Taher, an expert in the design of low-rise buildings for extreme winds and hurricane, hopes her phone won't ring much this hurricane season. It's already been busy with requests for information about best building design and construction practices to reduce wind pressures on building surfaces.

Weird orbits of neighbors can make 'habitable' planets not so habitable
Astronomers hunting for planets orbiting nearby stars similar to the sun are looking for signs of rocky, Earth-like planets in a "habitable" zone, where conditions such as temperature and liquid water remain stable enough to support life.

Odds are about 1-in-3 that a mega-earthquake will hit the Northwest in the next 50 years
The major earthquakes that devastated Chile earlier this year and which triggered the catastrophic Indonesian tsunami of 2004 are more than just a distinct possibility to strike the Pacific Northwest coast of the United States, scientists say.

More Earthquake Current Events and Earthquake News Articles

	Earthquakes (reillustrated) (Let's-Read-and-Find-Out Science 2) by Franklyn M. Branley (Author), Megan Lloyd (Illustrator) Read and find out about one of nature's most mysterious forces—the earthquake. Some earthquakes are so small that you don't even feel them, while others can make even big buildings shake! Learn why earthquakes happen, where they are most likely to occur, and what to do if one happens near you.
	Earthquake Starring: Charlton Heston, Ava Gardner, George Kennedy, Lorne Greene, Geneviève Bujold Charlton Heston leads an all-star cast in an epic film about ordinary citizens who must come together in the face of an unstoppable natural disaster! When the most catastrophic earthquake of all time rips through Southern California, it levels Los Angeles and sends shockwaves through the lives of all who live there. Now strangers must become heroes as the city struggles to get to its feet before the next terrifying aftershock hits! Also starring Ava Gardner, George Kennedy, Lorne Greene, Victoria Principal, Genevieve Bujold and Richard Roundtree, Earthquake combines outstanding performances with Academy Award-winning sound and groundbreaking special effects.
	Earthquakes by Seymour Simon (Author) Exceptional nonfiction for children from two of the most trusted names in science education: Seymour Simon and the Smithsonian Institution.
	Earthquake [VHS] Starring: Charlton Heston, Ava Gardner, George Kennedy, Lorne Greene, Geneviève Bujold Directed By: Mark Robson Also With: Philip H. Lathrop (Cinematographer), Mark Robson (Producer), Dorothy Spencer (Editor), Bernard Donnenfeld (Producer), Jennings Lang (Producer), George Fox (Writer), Mario Puzo (Writer) The disaster-movie trend of the early and mid-1970s was starting to wear out its welcome when Earthquake was released in 1974. It’s another one of those enjoyably mindless all-star marathons, and the title tells you all you need to know about the plot. Charlton Heston offers his trademark brand of macho courage as the citizens of Los Angeles brace for the Big One--an earthquake that rattles the city to its crumbling foundation. It's got all the sophistication of a Love Boat episode, but the movie's momentum scores high marks (at least on the Richter scale), and the Oscar-winning sound design and special visual effects are still impressive, especially when you consider that advanced computer-graphics effects were still two decades in the future. Genevieve Bujold adds a touch of class to...
	Earthshaking Science: What We Know (and Don't Know) about Earthquakes by Susan Hough (Author) This is the first book to really make sense of the dizzying array of information that has emerged in recent decades about earthquakes. Susan Hough, a research seismologist in one of North America's most active earthquake zones and an expert at communicating this complex science to the public, separates fact from fiction. She fills in many of the blanks that remained after plate tectonics theory, in the 1960s, first gave us a rough idea of just what earthquakes are about. How do earthquakes start? How do they stop? Do earthquakes occur at regular intervals on faults? If not, why not? Are earthquakes predictable? How hard will the ground shake following an earthquake of a given magnitude? How does one quantify future seismic hazard? As Hough recounts in brisk, jargon-free prose,...
	The San Francisco calamity by earthquake and fire by Charles Morris (Author) The San Francisco calamity by earthquake and fire is presented here in a high quality paperback edition. This popular classic work by Charles Morris is in the English language. If you enjoy the works of Charles Morris then we highly recommend this publication for your book collection.
	Deluxe 2-Person by SurvivalKitsOnline Perfect Survival Kit for Emergency Disaster Preparedness for Earthquake, Hurricane, Fire, Evacuations, Auto, Home and Family by SurvivalKitsOnline All items are packed securely in our Deluxe Hikers Backpack which contains extra space available for your personal items Food & Water: 24 - Pouches of Datrex Water - twice the amount of water as leading suppliers & each pouch has a 5 year shelf-life 24 - 200 Calorie Food Bars - 5 year shelf-life Light & Communication: Am/Fm Radio with Headphones & Batteries Rechargeable Squeeze Flashlight - contains lithium batteries which last up to 30 hours & also is able to generate power through squeezing 5-in-1 Survival Whistle - compass, signal mirror, flint starter, waterproof container,lanyard & shrill whistle 2 Green Emergency Light sticks Box of 50 Waterproof Matches Shelter & Warmth: Emergency Survival Sleeping Bag - Recommended over common "space blankets" 2 - 16 Hour Body Warmer 1 - 2...
	Earthquake Presents: From the Outhouse to the Whitehouse Starring: Dominique, Don "DC" Curry, Sheryl Underwood, Joe Clair Directed By: Michael Drumm A Black man in the White House? Amazing! And so is this must-have stand-up comedy show featuring a six-pack of comedians who hilariously reflect on President Barack Obamas historic election and what it means for America. Taking us from the outhouse to the White House are host Earthquake (Everybody Hates Chris), Sheryl Underwood (BETs Comic View), Joe Clair (longtime host of BETs Rap City), Don DC Curry (Next Friday), Dominique and Dez White. Earthquake also takes us backstage to get to know our comedians better and serves as our personal guide around the nations capital, his hometown.
	Peace of Mind in Earthquake Country: How to Save Your Home, Business, and Life by Peter Yanev (Author), Andrew C.T. Thompson (Author) In this updated and expanded third edition, seismic engineer Peter Yanev and risk management consultant Andrew Thompson explain how to prepare one's property to withstand a powerful quake, and how to protect one's family during and after the chaos. Residents of earthquake country learn why and how earthquakes occur, which construction methods are best suited for fault zones, and how to shore up existing buildings to survive the next big one. This comprehensive resource deconstructs complicated insurance policies, maps existing and suspected faults, and demystifies terms like "liquifaction" and "cripple walls."
	One Night Stand: Earthquake Starring: Dan Avey, Dom Irrera, Bill Maher, Judy Tenuta, Ellen DeGeneres Directed By: Peter Calabrese, Robin Shlien Also With: Richard Ocean (Cinematographer), Vic Lowrey (Editor) He?s big. He?s bad. And in the world of standup, Earthquake is a major force to be reckoned with.You?ve seen him on ?Premium Blend? and ?Mad TV.? Now see Earthquake set off comic tremors in front of an appreciative New York audience for a special One Night Stand performance. Commenting on real-life experiences and commonsense observations, Earthquake will draw you into his world?and shake you up with the explosiveness of his humor.