Science Current Events | Science News | Brightsurf.com
 
Email a Friend Send to a friend
Printer Friendly Print Scientists offer new model for forecasting the likelihood of an earthquake
Slashdot It! Slashdot Scientists offer new model for forecasting the likelihood of an earthquake
Submit to Reddit Submit Scientists offer new model for forecasting the likelihood of an earthquake to Reddit
Reading: Scientists offer new model for forecasting the likelihood of an earthquakeTwitter This Reading: Scientists offer new model for forecasting the likelihood of an earthquakeTwitter Scientists offer new model for forecasting the likelihood of an earthquake
Add to Facebook Add Scientists offer new model for forecasting the likelihood of an earthquake to Facebook

Scientists offer new model for forecasting the likelihood of an earthquake

December 11, 2006

In assessing the probability of an earthquake, scientists rely on two important pieces of data that are often inconsistent. The past geological record sometimes tells one story, while current measurements from the Global Positioning System (GPS) tell another. But a new forecasting model designed by Stanford University geophysicists may help close the gap.

"This is the most realistic model to date," said Kaj Johnson, assistant professor of geological sciences at Indiana University, who worked on the modeling project several years ago when he was a Stanford graduate student. "This is something people had been asking for years now. It's the next step."




Johnson and Stanford geophysics Professor Paul Segall will present their new probability model at 11:35 a.m. PT on Dec. 14, at the annual meeting of the American Geophysical Union in San Francisco during a talk titled "Distribution of Slip on San Francisco Bay Area Faults" in Room 307, Moscone Center South.

Measuring faults

An important component of earthquake-probability assessment is determining how fast a fault moves. One technique involves the use of GPS, which allows seismologists to measure the movement of various points on the surface of the Earth, then use these data to extrapolate underground fault movement. Another way to determine fault slip rates is to dig a trench across the fault and find the signatures of past earthquakes, a method called paleoseismology.

"People say, let's compare rates of fault movement from GPS to rates of fault movement from geologic studies," Segall said. "But it's as if you're measuring different parts of the same thing with different tools. The discrepancy can be quite big."

To bridge the gap, Segall and Johnson created a new model that weaves together everything known about how a fault moves. The idea for the model came when Segall was asked to speak at a conference on the "rate debate," which is how geophysicists refer to the GPS-paleoseismology discrepancy. That's when he realized that the standard model doesn't take into account that fault-slippage rates vary over time.

This time dependence is important, because GPS doesn't measure fault slippage directly. Rather, it measures how quickly points on the surface of the Earth are moving. Then scientists try to fit these data into mathematical models to estimate the rate of slip. "Because of the time-dependent rate, your estimate depends on where you are in the earthquake cycle," Segall said. "So if you use a model that doesn't take that into account, you will get a slip rate that's different."

The scientists hope that their new updated model can give a more accurate picture of slip rates and reconcile the two pieces of fault data.

California and Asia

With the new model, the team confirmed that the slip rates from GPS and from the geological record for the San Francisco Bay Area are relatively consistent. "Along the San Andreas system, the numbers tend to come out in reasonable agreement," Segall said.

The next step for the scientists is to use their time-dependent model to scrutinize faults in other tectonically active regions, such as China, where there is a large disparity between contemporary GPS data and the paleoseismological record. "We want to take the same philosophy and procedure and apply it to different places in the world where the discrepancy can be quite big," Segall noted. "We're developing a strategy for how to move forward. We're still very much in the progress phase."

Johnson is working on applying the new model to faults in Taiwan and Tibet, where the earthquake hazard is great. "This can help inform people who make the forecasts," Johnson said. "These new time-dependent models are going to become the norm, I think."

Stanford University





Science News and Science Current Events Tag Cloud
This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size.
Anxiety Disorders   DNA repair   Quantum Mechanics   Weight Loss   Myopia   Hiv-infected   Children   Antidepressant   Colonoscopy   Chemotherapy   White Blood Cells   Dengue   Stereotypes   Selenium   Fruit Fly   Amblyopia   Gene Mutation   Stomach Cancer   Sickle Cell   Drinking Water   Microbes   Prostate Cancer   Amino Acid   Morphine   Snowmelt  
Related Earthquake Current Events and Earthquake News Articles Earthquake Current Events and Earthquake News RSS Earthquake Current Events and Earthquake News RSS
New publication shows index insurance has potential to help manage climate risks and reduce poverty
Climate has always presented a challenge to farmers, herders, fishermen and others whose livelihoods are closely linked to their environment, particularly those in poor areas of the world.

Natural deep earth pump fuels earthquakes and ore
For the first time scientists have discovered the presence of a natural deep earth pump that is a crucial element in the formation of ore deposits and earthquakes.

NJIT expert advises on the do and don't of building in hurricane-prone areas
Better building practices for structures in hurricane-prone regions will be the focus of a paper next month in Caribbean Construction Magazine by NJIT architecture professor Rima Taher, PhD.

Predicted ground motions for great earthquake in Pacific Northwest: Seattle, Victoria and Vancouver
A new study evaluates expected ground motion in Seattle, Victoria and Vancouver from earthquakes of magnitude 7.5 - 9.0, providing engineers and policymakers with a new tool to build or retrofit structures to withstand seismic waves from large "subduction" earthquakes off the continent's west coast.

Frail elderly disaster
Planning for emergencies must take into account the growing numbers of frail elderly people who will by virtue of shifting demographics be involved in any natural or manmade disaster.

Princeton geoscientist offers new evidence that meteorite did not wipe out dinosaurs
A Princeton University geoscientist who has stirred controversy with her studies challenging a popular theory that an asteroid wiped out the dinosaurs has compiled powerful new evidence asserting her position.

Scripps Studies Offer New Picture of Lake Tahoe's Earthquake Potential
For more than a decade, scientists at Scripps Institution of Oceanography at UC San Diego have been unraveling the history of fault ruptures below the cobalt blue waters of Lake Tahoe one earthquake at a time.

New blow for dinosaur-killing asteroid theory
The enduringly popular theory that the Chicxulub crater holds the clue to the demise of the dinosaurs, along with some 65 percent of all species 65 million years ago, is challenged in a paper to be published in the Journal of the Geological Society on April 27, 2009.

BSSA special issue on rotational seismology
A special May issue of the Bulletin of the Seismological Society of America (BSSA) focuses on the emerging field of rotational seismology and its applications to engineering.

Self-healing concrete for safer, more durable infrastructure
A concrete material developed at the University of Michigan can heal itself when it cracks. No human intervention is necessary--just water and carbon dioxide.
More Earthquake Current Events and Earthquake News Articles
Earthquake

Earthquake
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)

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

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.



Platinum Comedy Series - Earthquake - About Got Damm Time

Platinum Comedy Series - Earthquake - About Got Damm Time
Starring: Earthquake
Directed By: Leslie Small
Also With: Earthquake (Producer), Walter Glover Jr. (Cinematographer), Leslie Small (Producer), Hector H. Kron (Editor), Janis Woody (Producer), Jeff Clanagan (Producer)

Platinum Comedy Series is the #1 stand up comedy DVD series in the country with over 1 million units sold! It is a series of live in concert comedy performances by fresh, talented performers.

Earthquake Alarm

Earthquake Alarm
by Jds Products

The Quake Alarm is designed to provide instant warning of seismic activity by detecting the "P" wave (compression wave) of an earthquake, which travels faster than the more destructive "S" wave (shear wave). The Quake Alarm saves valuable seconds by removing the guesswork in earthquake detection. It is capable of detecting large earthquakes that occur hundreds of miles away and can detect moderate to minor earthquakes for many miles around your local area. One very important advantage of the Quake Alarm is that it can wake you up and alert you the moment the quake starts so that you can immediately take cover or tend to other family members. The Quake Alarm can eliminate confusion, save valuable seconds and provide peace of mind.

Earthquake: Original Motion Picture Soundtrack

Earthquake: Original Motion Picture Soundtrack
John Williams (Composer)



Survival Kit Deluxe Emergency Disaster Preparedness 72 Hour Backpack Kits for Home, Work or Auto: 2 Person

Survival Kit Deluxe Emergency Disaster Preparedness 72 Hour Backpack Kits for Home, Work or Auto: 2 Person
by SurvivalKitsOnline

All items are packed securely by Survival Kits Online in a Deluxe Hikers Backpack which contains extra space available for your personal items. The kit includes the following: Food and Water: 12 - Boxes of Aqua Blox Water Boxes - twice the amount of water as leading suppliers and each box has a 5 year shelf-life 24 - 200 Calorie Food Bars - 5 year shelf-life 20 - Water Purification Tablets - each tablet purifies 1 liter of waterLight and Communication: Am/Fm Radio with Headphones and Batteries Rechargeable Squeeze Flashlight - contains lithium batteries which last up to 30 hours and also is able to generate power through squeezing 5-in-1 Survival Whistle - compass, signal mirror, flint starter, waterproof container,lanyard and shrill whistle 2 - Green Emergency Lightsticks Made in the...

Earthquakes (reillustrated) (Let's-Read-and-Find-Out Science 2)

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.



One Night Stand: Earthquake

One Night Stand: Earthquake
Directed By: Steven J. Santos, John Fortenberry, David Grossman (III), Robin Shlien, Sue Wolf

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.

Earthquake SuperNova MKV 15

Earthquake SuperNova MKV 15
by Earthquake Sound

* Color Options * Black and Cherry Vaneer One Magma-15 active driver Double Stacked 1.5" Max Gauss Magnets, 7" Epoxy coated Super SpiderSuper Wide Edge thermally pressed 1" surround, 3" XMax * One SLAPS-15 passive radiator * One BA212 - 590 watts digital amp 99% efficient, Optical Distortion Limiting circuit * Multi-position remote sensor & control * 24 dB per Octave Crossover variable from 50-150 Hz * Dimension 19" x 19" x 19" * Weight 98 lbs Thunder Audio Video LightAV.com 877-390-1599

Earthquakes: 2006 Centennial Update

Earthquakes: 2006 Centennial Update
by Bruce Bolt (Author)

The ultimate introduction to seismology, written by distinguished scholar and Professor Bruce Bolt, of the University of California, Berkeley, this newly updated edition will provide the best foundation in the field for your introductory students.

© 2009 BrightSurf.com