 |
|
Why do earthquakes stop?
February 06, 2008The underlying structure of a fault determines whether an earthquake rupture will jump from one fault to another, magnifying its size and potential devastation. Understanding why some earthquakes terminate along a fault, while others jump or step-over a gap to another fault, is essential to forecasting the seismic hazard of complex fault systems, such as the San Andreas Fault.
In a paper published in this issue of BSSA, author David Oglesby of University of California at Riverside suggests that the pattern of stress at the end of the primary fault can strongly affect an earthquake's ability to jump to a secondary fault. He suggests that a smooth, gradual decrease in stress along a rupture results in slower rupture deceleration, less strain, less generation of seismic waves, and lowers the likelihood that the earthquake will jump to another fault.
In contrast, a stress pattern that terminates suddenly leads to abrupt rupture termination, higher strain, more seismic radiation, and a higher likelihood of the rupture jumping to a secondary fault. The results of this numerical study illustrate the importance of the slip gradient and the acceleration of the rupture front in determining the probability of a rupture jumping from one fault segment to another.
Seismological Society of America
Seismological Society of America
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.
Bacterial Infection Beetle Lithium Preterm Birth Caloric Restriction Drug Addiction Chronic Kidney Disease Hormone Therapy Abdominal Fat Coffee Hearing Robots Pheromone Rett Syndrome Nuclear Medicine Caesarean Glioblastoma Biomarkers Hypertension Rabies Fat AIDS vaccine Saturn Sarcoma Reproduction
See More: Science News Tags
Earthquakes Current Events and Earthquakes News RSSObsidian 'trail' provides clues to how humans settled, interacted in Kuril Islands
Archaeologists have used stone tools to answer many questions about human ancestors in both the distant and near past and now they are analyzing the origin of obsidian flakes to better understand how people settled and interacted in the inhospitable Kuril Islands.
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.
New study closes in on geologic history of Earth's deep interior
By using a super-computer to virtually squeeze and heat iron-bearing minerals under conditions that would have existed when the Earth crystallized from an ocean of magma to its solid form 4.5 billion years ago, two UC Davis geochemists have produced the first picture of how different isotopes of iron were initially distributed in the solid Earth.
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.
A hidden drip, drip, drip beneath Earth's surface
There are very few places in the world where dynamic activity taking place beneath Earth's surface goes undetected.
Endangered right whales found where presumed extinct
Using a system of underwater hydrophones that can record sounds from hundreds of miles away, a team of scientists from Oregon State University and the National Oceanic and Atmospheric Administration has documented the presence of endangered North Atlantic right whales in an area they were thought to be extinct.
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.
Contrary to recent hypothesis, 'chevrons' are not evidence of megatsunamis
A persistent school of thought in recent years has held that so-called "chevrons," large U- or V-shaped formations found in some of the world's coastal areas, are evidence of megatsunamis caused by asteroids or comets slamming into the ocean.
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.
More Earthquakes Current Events and Earthquakes News Articles
 |
Nova: Earthquake the Science Behind the Shake Starring: Nova Directed By: n/a Included in this three disk set are: Earthquake, Killer Quake and |
 |
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. |
 |
Nature Tech - Earthquakes (History Channel) Starring: Artist Not Provided This explores the evolution of 21st century seismic technology to see what advancements are being made to assist seismologists & other researchers in the race to prevent the next earthshaking disaster. Studio: A&e Home Video Release Date: 04/24/2007 |
 |
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 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. |
 |
Little Earthquakes by Tori Amos Emotionally and musically intense, Little Earthquakes shows that the piano is as much a rock & roll instrument as the guitar. Tori Amos's debut (if one disregards Y Kant Tori Read, as one would be well advised to do) is at once listenable and challenging; she takes on every topic, from sex to gender to religion, in an uncompromising manner. Her music appears gentle at first, but this appearance is deceiving, as one quickly learns upon listening to the wrenching "Crucify" or the almost violent "Precious Things." By the time the album gets around to "Me and a Gun," sung hauntingly by Amos without accompaniment from her piano, the juxtaposition of Amos' sweet voice and the emotional complexity of her lyrics is both familiar and shocking. Sandman fans should listen for a reference to author... |
 |
SKO Survival Kit Deluxe Emergency Disaster Preparedness 72 Hour Backpack Kit Earthquake, Hurricane, Fire, Flood, Tornado, Evacuation or Storm. Home, Work or Auto: 4 Person by Survivalkitsonline Kit Includes: 1 x Backpack 4 x 2400 Cal. Food Bar U.S. Coast Guard Approved 5 Year Shelf-Life. 4 x Solar Blanket Made in the US 4 x 3 Pack of Water U.S. Coast Guard Approved 5 Year Shelf-Life. 4 x Dust Masks 4 x Ponchos 1 x Flashlight 2 x Code Red Batteries 1 x 2 Person Tent 1 x 50' Nylon Cord 1 x 12 Hour Light Stick Made in the US 1 x 54 Piece First Aid Kit 50 x Water Purification Tablets 50 x Waterproof Matches 1 x Utility Knife 1 x 5 in 1 Whistle 1 x AM/FM Radio with Batteries 1 x Campers Stove 1 x Pair Leather Palm Gloves |
 |
Earthquake Sound AK-5000 Complete Amplifier Installation Kit Triple Gold Plated 5000 Watts/ 4-Gauge by Earthquake Sound 80ft High- Power Cables for Amps, Speakers, and Head Unit * Over 20 Gold Plated terminals, connectors, screws and ties. * Red Power Wire: 17ft (5.18m); 4-Gauge * Black Ground Wire: 3ft (0.9m); 4-Gauge * Speaker Wire: 20ft (6.1m); 16-Gauge * Blue Remote Turn On Wire: 16ft (4.8m); 16-Gauge * Silver Twisted-Pair RCA Interconnect: 18ft (5.5m); Straight * Black Split Loom: 6ft (1.83m); OD 8mm * Gold Plated ANL Fuse Holder: ANL Fuse; 150A * 4x4 Gauge gold "O" ring terminal, 2 red/ 2 black * 2x4 Gauge gold "U" ring terminal, 1 red/ 1 black * 4x14-16 Gold "U" terminal for speaker terminals on amp, 2 red/ 2 black * 4x.25" Female disconnects for speakers, 2 red/ 2 black * 1x14-16 Gauge gold "U" terminal for remote turn-on wire, 1 black * 1x16-22 Gauge butt connector for remote turn-on... |
 |
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. |
 |
Nova: Earthquake Starring: Nova Directed By: Nova Will the earth send us a warning signal before the next "big one" strikes? Predicting earthquakes is risky business, but Earthquake shows how today's advanced technology helps geologists interpret nature's rumblings. |
| © 2009 BrightSurf.com |