Science Current Events | Science News | Brightsurf.com
 
Email a Friend Send to a friend
Printer Friendly Print California's central coast earthquake hazards: New information about recently identified faults

California's central coast earthquake hazards: New information about recently identified faults

April 09, 2009

Seismologists are re-evaluating the earthquake potential of the Central Coast, a very complex tectonic region located west of the San Andreas Fault, between Monterey Bay and the Western Transverse Ranges. This area of increasing population growth ranks as one of the top 40 U.S. metropolitan areas with significant earthquake risk.

Speakers from the US Geological Survey, PG&E and academia will compare fresh data to illuminate the complexity of faulting in the central California coastal region.




Three talks will use separate datasets to focus on the California Central Ranges, Hosgri Fault Zone and nearby faults:

* Fault structure of the California Central Coast: Jeanne Hardebeck, US Geological Survey, will present and interpret new earthquake relocations and focal mechanisms for earthquakes occurring along the central California coast, including the offshore region near San Luis Obispo. A prominent newly-observed feature is a 25 km long linear trend of seismicity running just offshore and parallel to the coast-line in the region of Point Buchon. This seismicity trend is accompanied by a linear magnetic anomaly, and both the seismicity and the magnetic anomaly are truncated where they obliquely meet the Hosgri Fault. Focal mechanisms indicate that this feature is a vertical strike-slip fault.

* Geophysical characterization of the Hosgri Fault zone: High-resolution marine magnetic and seismic-reflection data collected offshore Point Buchon show that the Hosgri Fault represents a complex zone of steeply dipping faults that varies significantly in character along strike. The boundary of a northwest-trending linear magnetic anomaly off Point Buchon corresponds to a linear trend of small earthquakes, suggesting an active fault. Continued interpretation and geophysical modeling of magnetic, seismic reflection, and seismicity data will help determine whether or not the magnetic boundaries are fault boundaries, and if so, how these structures relate to the Hosgri Fault Zone.

* Constraints on 3-dimensional structure from gravity and magnetic data: V. E. Langenheim, US Geological Survey, will present analysis based on a new physical dataset that is sensitive to magnetic properties of rock, mapping fault boundaries. Her research suggests complex, non-linear features with intersecting faults. Fault and basin geometry will be important for estimating shaking potential of scenario earthquakes.

Seismological Society of America



Related Fault Zone Current Events and Fault Zone News Articles Fault Zone Current Events and Fault Zone News RSS Fault Zone Current Events and Fault Zone News RSS
Satellite data look behind the scenes of deadly earthquake
Using satellite radar data and GPS measurements, Chinese researchers have explained the exceptional geological events leading to the 2008 Wenchuan Earthquake that killed nearly 90 000 people in China's Sichuan Province.

First complete image created of Himalayan fault, subduction zone
An international team of researchers has created the most complete seismic image of the Earth's crust and upper mantle beneath the rugged Himalaya Mountains, in the process discovering some unusual geologic features that may explain how the region has evolved.

Scientists return from first ever riser drilling operations in seismogenic zone
he Deep-sea Drilling Vessel CHIKYU successfully completed riser drilling operations on Aug. 31, for IODP Expedition 319, Stage 2 of the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE).

Listening to rocks helps researchers better understand earthquakes
When Apollo punished King Midas by giving him donkey ears, only the king and his barber knew. Unable to keep a secret, the barber dug a hole, whispered into it, "King Midas has donkey ears," and filled the hole. But plants sprouted from the hole, and with each passing breeze, shared the king's secret.

Tremors on southern San Andreas Fault may mean increased earthquake risk
Increases in mysterious underground tremors observed in several active earthquake fault zones around the world could signal a build-up of stress at locked segments of the faults and presumably an increased likelihood of a major quake, according to a new University of California, Berkeley, study.

Understanding risk to Seattle's high-rise buildings from a giant Cascadian earthquake
The Cascadia subduction zone is likely to produce the strongest shaking experienced in the lower 48 states. Although seismic activity in the Pacific Northwest has been relatively low in the past two centuries, there is a growing consensus that this fault zone ruptures in giant earthquakes (magnitude exceeding 9); the last rupture is inferred to have occurred in 1700.

Potential for another large earthquake off the coast of Sumatra, say scientists
Three great earthquakes and destructive tsunamis over the past four years is not enough to spare the region of another large earthquake, warns an international group of earthquake researchers in their paper published in the 4 December issue of the journal Nature.

May 2008 earthquake in China could be followed by another significant rupture
Researchers analyzing the May 2008 Wenchuan earthquake in China's Sichuan province have found that geological stress has significantly increased on three major fault systems in the region.

Stress Buildup Precedes Large Sumatra Quakes
The island of Sumatra, Indonesia, has shaken many times with powerful earthquakes since the one that wrought the infamous 2004 Indian Ocean tsunami. Now, scientists from the California Institute of Technology and the Indonesian Institute of Sciences are harnessing information from these and earlier quakes to determine where the next ones will likely occur, and how big they will be.

Researchers at UCLA engineering discover theoretical model to predict jamming
Researchers at the UCLA Henry Samueli School of Engineering and Applied Science have come up with a theoretical model to predict when granular materials become jammed.
More Fault Zone Current Events and Fault Zone News Articles
Point Reyes and the San Andreas Fault Zone

Point Reyes and the San Andreas Fault Zone
by Frank Binney (Author)

The wild coastline and spectacular scenery of one of America s greatest natural treasures have been uniquely captured in this emotive collection of fine art photographs by internationally acclaimed aerial photographer Robert Campbell. For almost 40 years Campbell has made repeated flights over the Point Reyes peninsula and the adjacent San Andreas Fault Zone, interpreting the countryside in unique compositions as the weather and seasons change.
Some of his striking photographs reveal recognizable landmarks in views beyond our land bound experience a stunning panorama of the Point Reyes Lighthouse, for example, taken from a seabird s perspective. Other images, no less powerful, frame small details and patterns on the ground that speak to us with their abstract beauty. Campbell s...

Fault Zone Tunnel

Fault Zone Tunnel
Also With: Discovery Channel (Producer)



Build it Bigger Season 1 - Boot Camp & Fault Zone Tunnel

Build it Bigger Season 1 - Boot Camp & Fault Zone Tunnel

Travel the world to break down the most astounding, complex engineering feats to date with architect Danny Forster. From the skyscrapers of Dubai to the amusement parks of Minnesota, explore the design and structure of these mega-constructions while learning first-hand knowledge and background facts about each site. Working with designers, engineers, builders, and those who work on these structures, discover the most dangerous, ingeniously executed aspects of each job. Boot Camp. Danny Forster's been on job sites all over the world, but to really learn how to operate construction equipment, he gets a crash course in everything from heavy equipment operation to getting lunch for the foreman. Fault Zone Tunnel. Go inside one of the most difficult and dangerous tunneling projects in the...

Mechanics, Structure and Evolution of Fault Zones (Pageoph Topical Volumes)

Mechanics, Structure and Evolution of Fault Zones (Pageoph Topical Volumes)
by Yehuda Ben-Zion (Editor), Charles Sammis (Editor)

Considerable progress has been made recently in quantifying geometrical and physical
properties of fault surfaces and adjacent fractured and granulated damage zones in
active faulting environments. There has also been significant progress in developing
rheologies and computational frameworks that can model the dynamics of fault zone
processes. This volume provides state-of-the-art theoretical and observational results
on the mechanics, structure and evolution of fault zones. Subjects discussed include
damage rheologies, development of instabilities, fracture and friction, dynamic rupture
experiments, and analyses of earthquake and fault zone data.



Flow Processes in Faults And Shear Zones (Geological Society Special Publication) (No. 224)

Flow Processes in Faults And Shear Zones (Geological Society Special Publication) (No. 224)
by G. I. Alsop (Author)

Faults and their deeper level equivalents, shear zones, are localized regions of intense deformation within the Earth. They are recognized at all scales from micro to plate boundary, and are important examples of the nature of heterogeneous deformation in natural rocks. Faults and shear zones are significant as they profoundly influence the location, architecture and evolution of a broad range of geological phenomena. The topography and bathymetry of the Earth's surface is marked by mountain belts and sedimentary basins which are controlled by faults and shear zones. In addition faults and shear zones control fluid migration and transport including hydrothermal and hydrocarbon systems. Once faults and shear zones are established, they are often long-lived features prone to multiple...

Fault-Zone Properties and Earthquake Rupture Dynamics, Volume 94 (International Geophysics)

Fault-Zone Properties and Earthquake Rupture Dynamics, Volume 94 (International Geophysics)
by Eiichi Fukuyama (Editor)

The dynamics of the earthquake rupture process are closely related to fault zone properties which the authors have intensively investigated by various observations in the field as well as by laboratory experiments. These include geological investigation of the active and fossil faults, physical and chemical features obtained by the laboratory experiments, as well as the seismological estimation from seismic waveforms. Earthquake dynamic rupture can now be modeled using numerical simulations on the basis of field and laboratory observations, which should be very useful for understanding earthquake rupture dynamics.

Features:
* First overview of new and improved techniques in the study of earthquake faulting
* Broad coverage
* Full...

  Annotated Map of the San Andreas Fault Zone, Leona Valley Area, Southern California
by J. C. Kahle (Author)



  Tectonic creep in the Hayward fault zone, California
by United States Geological Survey. (Author)



Hayward Fault Zone

Hayward Fault Zone
by Frederic P. Miller (Editor), Agnes F. Vandome (Editor), John McBrewster (Editor)

Hayward Fault Zone. Fault (geology), Seafloor spreading, Subduction, Plate tectonics, Earthquake, Bay mud, Soil liquefaction, Landslide, Bay Area Rapid Transit, Seismic retrofit

New Madrid Fault Finders Guide: A Set of Self-Guided Field Tours in the "World's Greatest Outdoor Earthquake Laboratory" : The New Madrid Fault Zone

New Madrid Fault Finders Guide: A Set of Self-Guided Field Tours in the "World's Greatest Outdoor Earthquake Laboratory" : The New Madrid Fault Zone
by Ray Knox (Author), David Stewart (Author), Kate Schaefer (Illustrator)

The greatest sequence of earthquakes in the history of the lower 48 states took place in 1811-12 along the Mississippi River between Missouri, Arkansas, Tennessee and Kentucky. These unprecedented and unsurpassed cataclysms left more than 5,000 square miles of permanently disturbed earth manifesting thousands of faults, fissures, landslides, sand boils, and other morphoseismic landforms. This book is a set of self-guided tours of the New Madrid Seismic Zone, complete with maps, detailed road logs, photographs, and a guide to the best restaurantes and local cuisine. See for yourself. take a day. Spend a weekend. Take an earthquake vacation. Visit the most active fault zone in Mid-America. Drive down "Earthquake Alley." Fall into an earthquake crevasse. Walk on a sand boil....

© 2009 BrightSurf.com