Featured Research

from universities, journals, and other organizations

Magnitude of maximum earthquake scales with maturity of fault

Date:
April 30, 2014
Source:
Seismological Society of America
Summary:
The oldest sections of transform faults, such as the North Anatolian Fault Zone and the San Andreas Fault, produce the largest earthquakes, putting important limits on the potential seismic hazard for less mature parts of fault zones, according to a new study. The finding suggests that maximum earthquake magnitude scales with the maturity of the fault.

The oldest sections of transform faults, such as the North Anatolian Fault Zone (NAFZ) and the San Andreas Fault, produce the largest earthquakes, putting important limits on the potential seismic hazard for less mature parts of fault zones, according to a new study to be presented today at the Seismological Society of America (SSA) 2014 Annual Meeting in Anchorage, Alaska. The finding suggests that maximum earthquake magnitude scales with the maturity of the fault.

Identifying the likely maximum magnitude for the NAFZ is critical for seismic hazard assessments, particularly given its proximity to Istanbul.

"It has been argued for decades that fault systems evolving over geological time may unify smaller fault segments, forming mature rupture zones with a potential for larger earthquake," said Marco Bohnhoff, professor of geophysics at the German Research Center for Geosciences in Potsdam, Germany, who sought to clarify the seismic hazard potential from the NAFZ. "With the outcome of this study it would in principal be possible to improve the seismic hazard estimates for any transform fault near a population center, once its maturity can be quantified," said Bohnhoff.

Bohnhoff and colleagues investigated the maximum magnitude of historic earthquakes along the NAFZ, which poses significant seismic hazard to northwest Turkey and, specifically, Istanbul.

Relying on the region's extensive literary sources that date back more than 2000 years, Bohnhoff and colleagues used catalogues of historical earthquakes in the region, analyzing the earthquake magnitude in relation to the fault-zone age and cumulative offset across the fault, including recent findings on fault-zone segmentation along the NAFZ.

"What we know of the fault zone is that it originated approximately 12 million years ago in the east and migrated to the west," said Bohnhoff. "In the eastern portion of the fault zone, individual fault segments are longer and the offsets are larger."

The largest earthquakes of approximately M 8.0 are exclusively observed along the older eastern section of the fault zone, says Bohnhoff. The younger western sections, in contrast, have historically produced earthquakes of magnitude no larger than 7.4.

"While a 7.4 earthquake is significant, this study puts a limit on the current seismic hazard to northwest Turkey and its largest regional population and economical center Istanbul," said Bohnhoff.

Bohnhoff compared the study of the NAFZ to the San Andreas and the Dead Sea Transform Fault systems. While the earlier is well studied instrumentally with few historic records, the latter has an extensive record of historical earthquakes but few available modern fault-zone investigations. Both of these major transform fault systems support the findings for the NAFZ that were derived based on a unique combination of long historical earthquake records and in-depth fault-zone studies.

Bohnhoff will present his study, "Fault-Zone Maturity Defines Maximum Earthquake Magnitude," today at the SSA Annual Meeting. SSA is an international scientific society devoted to the advancement of seismology and the understanding of earthquakes for the benefit of society. Its 2014 Annual Meeting will be held Anchorage, Alaska on April 30 -- May 2, 2014.


Story Source:

The above story is based on materials provided by Seismological Society of America. Note: Materials may be edited for content and length.


Cite This Page:

Seismological Society of America. "Magnitude of maximum earthquake scales with maturity of fault." ScienceDaily. ScienceDaily, 30 April 2014. <www.sciencedaily.com/releases/2014/04/140430083139.htm>.
Seismological Society of America. (2014, April 30). Magnitude of maximum earthquake scales with maturity of fault. ScienceDaily. Retrieved July 26, 2014 from www.sciencedaily.com/releases/2014/04/140430083139.htm
Seismological Society of America. "Magnitude of maximum earthquake scales with maturity of fault." ScienceDaily. www.sciencedaily.com/releases/2014/04/140430083139.htm (accessed July 26, 2014).

Share This




More Earth & Climate News

Saturday, July 26, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Virginia Governor Tours Tornado Aftermath

Virginia Governor Tours Tornado Aftermath

AP (July 25, 2014) Virginia Gov. Terry McAuliffe toured the Cherrystone Family Camping and RV Resort on the Chesapeake Bay today, a day after it was hit by a tornado. The storm claimed two lives and injured dozens of others. (July 25) Video provided by AP
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins