Featured Research

from universities, journals, and other organizations

Early Warning Systems Underestimate Magnitude Of Large Earthquakes

Date:
January 29, 2009
Source:
Seismological Society of America
Summary:
Scientists seek to create reliable early warning systems that accurately estimate the magnitude of an earthquake within the first seconds of rupture. Scientists looked at the idea that an earthquake's final size can be determined during its initiation, rather than something that only becomes apparent at the end of the rupture.

Scientists seek to create reliable early warning systems that accurately estimate the magnitude of an earthquake within the first seconds of rupture.

Related Articles


In a new paper published by the Bulletin of the Seismological Society of America, authors S. Murphy of University College Dublin, Ireland and S. Nielsen of the Instituto Nazionale di Geofisica e Vulcanologia, Roma, Italy look at the idea that an earthquake's final size can be determined during its initiation, rather than something that only becomes apparent at the end of the rupture. They found that, while this may be true over a small range of earthquake sizes, it is unlikely to hold for the larger magnitudes, limiting its applicability for early warning systems.

Alternatively, the authors found that rapid magnitude estimation could be better explained in terms of what seismic stations capture of an earthquake in a few seconds. This section is generally quite large and is dependent on the relative position of the station to the fault. Therefore using a number of seismic stations around an earthquake fault, as is the case in early warning systems, the size of the earthquake can be quickly estimated.

This explanation shows a scaling between ground motion and final earthquake size similar to that observed from seismograms. The authors found that this relationship breaks down for very large earthquakes, i.e. earthquakes with a magnitude greater than 6.5. In these cases, the seismic stations no longer capture the edges of the fault in a few seconds due to the large area of the fault. When this happens, the authors suggest that early warning systems which use the peak ground displacement technique for estimating earthquake size, shall underestimate the size of the earthquake.


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. "Early Warning Systems Underestimate Magnitude Of Large Earthquakes." ScienceDaily. ScienceDaily, 29 January 2009. <www.sciencedaily.com/releases/2009/01/090128160818.htm>.
Seismological Society of America. (2009, January 29). Early Warning Systems Underestimate Magnitude Of Large Earthquakes. ScienceDaily. Retrieved November 22, 2014 from www.sciencedaily.com/releases/2009/01/090128160818.htm
Seismological Society of America. "Early Warning Systems Underestimate Magnitude Of Large Earthquakes." ScienceDaily. www.sciencedaily.com/releases/2009/01/090128160818.htm (accessed November 22, 2014).

Share This


More From ScienceDaily



More Earth & Climate News

Saturday, November 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

Toyota's Hydrogen Fuel-Cell Green Car Soon Available in the US

AFP (Nov. 21, 2014) Toyota presented its hydrogen fuel-cell compact car called "Mirai" to US consumers at the Los Angeles auto show. The car should go on sale in 2015 for around $60.000. It combines stored hydrogen with oxygen to generate its own power. Duration: 01:18 Video provided by AFP
Powered by NewsLook.com
Google Announces Improvements To Balloon-Borne Wi-Fi Project

Google Announces Improvements To Balloon-Borne Wi-Fi Project

Newsy (Nov. 21, 2014) In a blog post, Google said its balloons have traveled 3 million kilometers since the start of Project Loon. Video provided by Newsy
Powered by NewsLook.com
5 Hot Months, 1 Warm Year And All The Arguments To Follow

5 Hot Months, 1 Warm Year And All The Arguments To Follow

Newsy (Nov. 21, 2014) The NOAA released statistics Thursday showing October was the fifth month this year with record temps and 2014 will likely be the hottest on record. Video provided by Newsy
Powered by NewsLook.com
Nations Pledge $9.3 Bn for Green Climate Fund

Nations Pledge $9.3 Bn for Green Climate Fund

AFP (Nov. 20, 2014) Nations meeting in Berlin pledge $9.3 billion (7.4 bn euros) for a climate fund to help poor countries cut emissions and prepare for global warming, just shy of a $10bn target. Duration: 00:46 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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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