Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New UCSB earthquake study improves model, shows hazard to structures located near the fault

12.03.2003


Thanks to recent advances in parallel computing, an interdisciplinary team of scientists at the University of California, Santa Barbara has discovered a peculiar and important aspect of how seismic waves are generated during an earthquake. The results are published in the March 7 edition of Science Magazine.



The team, whose work is supported by the Keck Foundation, was composed of physics graduate student Eric M. Dunham, professor of physics Jean M. Carlson, and postdoctoral researcher Pascal Favreau, who was based at UCSB’s Institute for Crustal Studies. They modeled earthquakes using computer simulations of rapidly expanding three-dimensional ruptures along faults. They found that sections of the fault with increased material strength (called barriers) focus the earthquake’s energy to an unexpected degree. This result comes as a surprise, since hard-to-break barriers were previously considered obstacles to the growing rupture.

The energy concentration has several important implications. When barriers break, they release intense bursts of seismic waves that pose significant hazards to structures located near the fault. This explains puzzling records of the 1984 Morgan Hill earthquake that struck the area south of San Jose, California. During this quake there was an intense pulse of ground shaking traced to a high strength region of the fault, rather than the rupture front which is typically the source of the strongest seismic waves. Furthermore, the researchers are the first to show how this energy concentration drives the rupture ahead of where it would have been had the fault been easier to break.


They showed that the rupture can even propagate faster than shear wave speed, typically considered the speed limit of growing earthquakes. This "supershear" propagation, once regarded as a mathematical curiosity, has become an area of growing interest after experimental observations gave support to controversial reports of supershear bursts occurring during several major earthquakes.


First author Eric Dunham was awarded Outstanding Student Paper from the American Geophysical Union for this article. Jean Carlson and Pascal Favreau are listed as co-authors.

Gail Gallessich | EurekAlert!
Further information:
http://www.ucsb.edu/

More articles from Earth Sciences:

nachricht NASA sees quick development of Hurricane Dora
27.06.2017 | NASA/Goddard Space Flight Center

nachricht Collapse of the European ice sheet caused chaos
27.06.2017 | CAGE - Center for Arctic Gas Hydrate, Climate and Environment

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>