Navigation Links
Alpine Fault study shows new evidence for regular magnitude 8 earthquakes
Date:7/25/2012

RENO, Nev. A new study published in the prestigious journal Science, co-authored by University of Nevada, Reno's Glenn Biasi and colleagues at GNS Science in New Zealand, finds that very large earthquakes have been occurring relatively regularly on the Alpine Fault along the southwest coastline of New Zealand for at least 8,000 years.

The Alpine Fault is the most hazardous fault on the South Island of New Zealand, and about 80 miles northwest of the South Island's main city of Christchurch.

The team developed evidence for 22 earthquakes at the Hokuri Creek site, which, with two additional from nearby, led to the longest continuous earthquake record in the world for a major plate boundary fault. The team established that the Alpine Fault causes, on average, earthquakes of around a magnitude 8 every 330 years. Previous data put the intervals at about 485 years.

Relative motion of Australian and Pacific plates across the Alpine Fault averages almost an inch per year. This motion builds up, and then is released suddenly in large earthquakes. The 530-mile-long fault is among the longest, straightest and fastest moving plate boundary faults in the world. More than 23 feet of potential slip has accumulated in the 295 years since the most recent event in A.D. 1717.

Biasi, working with the GNS Science team led by Kelvin Berryman, used paleoseismology to extend the known seismic record from 1000 years ago to 8,000 years ago. They estimated earthquake dates by combining radiocarbon dating leaves, small twigs and marsh plants with geologic and other field techniques.

"Our study sheds new light on the frequency and size of earthquakes on the Alpine Fault. Earthquakes have been relatively periodic, suggesting that this may be a more general property of simple plate boundary faults worldwide," Biasi, of the Nevada Seismological Laboratory said. "By comparison, large earthquakes on California's San Andreas Fault have been less regular in size and timing."

"Knowing the average rate of earthquakes is useful, but is only part of the seismic hazard equation," he said. "If they are random in time, then the hazard does not depend on how long it has been since the most recent event. Alpine Fault earthquakes are more regular in their timing, allowing us to use the time since the last earthquake to adjust the hazard estimate. We estimate the 50-year probability of a large Alpine fault earthquake to be about 27 percent."

A magnitude 7.1 earthquake centered near Christchurch, the largest city in the South Island of New Zealand, caused extensive damage to buildings on Sept. 2, 2010, and no deaths. On Feb. 22, 2011, a triggered aftershock measuring magnitude 6.3, with one of the strongest ground motions ever recorded worldwide in an urban area, struck the city killing 185 people.


'/>"/>

Contact: Mike Wolterbeek
mwolterbeek@unr.edu
University of Nevada, Reno
Source:Eurekalert  

Related biology news :

1. Friendly to a fault, yet tense: Personality traits traced in brain
2. Johns Hopkins researchers uncover genes at fault for cystic fibrosis-related intestinal obstruction
3. Understanding faults and volcanics, plus life inside a rock
4. Study by UC Santa Barbara researchers suggests that bacteria communicate by touch
5. Law that regulates shark fishery is too liberal: UBC study
6. New study will help protect vulnerable birds from impacts of climate change
7. Study jointly led by UCSB researcher supports theory of extraterrestrial impact
8. BYU study: Using a gun in bear encounters doesnt make you safer
9. 15-year study: When it comes to creating wetlands, Mother Nature is in charge
10. Pycnogenol (French maritime pine bark extract) shown to improve menopause symptoms in new study
11. Crystal structure of archael chromatin clarified in new study
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Alpine Fault study shows new evidence for regular magnitude 8 earthquakes
(Date:4/5/2017)... Allen Institute for Cell Science today announces the launch ... dynamic digital window into the human cell. The website ... deep learning to create predictive models of cell organization, ... suite of powerful tools. The Allen Cell Explorer will ... resources created and shared by the Allen Institute for ...
(Date:4/4/2017)... 4, 2017   EyeLock LLC , a leader ... United States Patent and Trademark Office (USPTO) has issued ... linking of an iris image with a face image ... the company,s 45 th issued patent. ... timely given the multi-modal biometric capabilities that have recently ...
(Date:3/30/2017)... 2017 The research team of The Hong ... fingerprint identification by adopting ground breaking 3D fingerprint minutiae recovery and ... speed and accuracy for use in identification, crime investigation, immigration control, ... ... A research team led ...
Breaking Biology News(10 mins):
(Date:10/12/2017)... , ... October 12, 2017 ... ... announces publication of a United States multicenter, prospective clinical study that demonstrates ... point-of-care diagnostic test capable of identifying clinically significant acute bacterial and viral ...
(Date:10/11/2017)... ... 2017 , ... At its national board meeting in North ... the co-founder, CEO and chief research scientist of Minnesota-based Advanced Space Technology and ... ARCS Alumni Hall of Fame . ASTER Labs is a technology development ...
(Date:10/11/2017)... Md. (PRWEB) , ... October 11, 2017 , ... ... digital pathology, announced today it will be hosting a Webinar titled, “Pathology is ... Advanced Pathology Associates , on digital pathology adoption best practices and how Proscia ...
(Date:10/11/2017)... ... October 11, 2017 , ... A new study published in ... and fresh in vitro fertilization (IVF) transfer cycles. The multi-center matched ... , After comparing the results from the fresh and frozen transfer cohorts, the ...
Breaking Biology Technology: