Featured Research

from universities, journals, and other organizations

Characteristics of Earthquakes that Have Caused Exceptional Ground Accelerations and Velocities

Date:
February 8, 2010
Source:
Seismological Society of America
Summary:
A new study identifies earthquakes through July 2007 that have produced 100 of the strongest peak accelerations and 100 of the strongest peak velocities ever recorded.

A new study identifies earthquakes through July 2007 that have produced 100 of the strongest peak accelerations (PGA) and 100 of the strongest peak velocities (PGV) ever recorded. The threshold for the first list is acceleration of the ground exceeding 7.31 m/s2 (74% of gravity), while the threshold for the second is velocity exceeding 0.65 m/s. Crustal earthquakes dominate the lists. Exceptionally strong ground motions exceeding these levels have been observed on sites with the softest soils and sites with the hardest rock.

Related Articles


Acceleration measures how fast speed (velocity) increases.

"The size of these ground motions matter to the engineers as they design structures to resist earthquakes," said John Anderson of the Nevada Seismological Laboratory and Department of Geological and Engineering Sciences at the University of Nevada. "But ground motions that have not yet been recorded also matter. There may be a limit that earthquake motions will never exceeded. Although we expect to eventually record earthquake shaking stronger than what I report in this paper, those higher motions appear to be quite rare, and a motivation for this study was to help to constrain upper limits.

Small earthquakes can generate exceptional peak accelerations (over 5 m/s2). This compilation includes earthquakes with magnitudes as small as 4.1. The smallest earthquake causing one of the 100 largest PGA on the list had a magnitude 4.8, and the smallest earthquake causing one of the 100 largest PGV was a magnitude 5.7.

Of the 255 time histories identified in this study, 40 records have PGV exceeding 1.0 m/s. The largest PGV is 3.18 m/s, recorded on the hanging wall of the thrust fault during the Chi-Chi, Taiwan earthquake on September 20, 1999 (Magnitude 7.6). Also, 35 records have PGA greater than gravity (9.8 m/s2, or 1 g). The largest acceleration in this data set is about 23.8 m/s2 (about 2.4 times gravity), recorded on the hanging wall of the thrust fault during the Nahanni earthquake in northern Canada on December 23, 1985 (Magnitude 6.9). It has already been exceeded by a 2008 record from Japan with PGA that was greater than 4.1 g,, but that later record was not available when this data was compiled.

While motions that large appear to be quite rare, with recent expansions of instruments, more records as large as those in the current top 100 are being obtained every year.


Story Source:

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


Journal Reference:

  1. Anderson et al. Source and Site Characteristics of Earthquakes That Have Caused Exceptional Ground Accelerations and Velocities. Bulletin of the Seismological Society of America, 2010; 100 (1): 1 DOI: 10.1785/0120080375

Cite This Page:

Seismological Society of America. "Characteristics of Earthquakes that Have Caused Exceptional Ground Accelerations and Velocities." ScienceDaily. ScienceDaily, 8 February 2010. <www.sciencedaily.com/releases/2010/02/100205102550.htm>.
Seismological Society of America. (2010, February 8). Characteristics of Earthquakes that Have Caused Exceptional Ground Accelerations and Velocities. ScienceDaily. Retrieved March 31, 2015 from www.sciencedaily.com/releases/2010/02/100205102550.htm
Seismological Society of America. "Characteristics of Earthquakes that Have Caused Exceptional Ground Accelerations and Velocities." ScienceDaily. www.sciencedaily.com/releases/2010/02/100205102550.htm (accessed March 31, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Tuesday, March 31, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

You Won't Be Driving Tesla's Mystery Product

You Won't Be Driving Tesla's Mystery Product

Newsy (Mar. 30, 2015) — Tesla CEO Elon Musk announced a new product line will debut April 30, but it&apos;s not a car. Video provided by Newsy
Powered by NewsLook.com
Solar Impulse Departs Myanmar for China

Solar Impulse Departs Myanmar for China

AFP (Mar. 30, 2015) — Solar Impulse 2 takes off from Myanmar&apos;s second biggest city of Mandalay and heads for China&apos;s Chongqing, the fifth flight of a landmark journey to circumnavigate the globe powered solely by the sun. Duration: 00:42 Video provided by AFP
Powered by NewsLook.com
Colombian Project Transforms Old Tires Into Green Housing

Colombian Project Transforms Old Tires Into Green Housing

AFP (Mar. 30, 2015) — To put a roof over their heads and help the environment, residents near Bogota are building houses out of recycled bottles and old tires. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
The Future Of Japanese Whaling: Heritage Vs. Conservation

The Future Of Japanese Whaling: Heritage Vs. Conservation

Newsy (Mar. 30, 2015) — In 2014, the International Court of Justice ruled Japan could no longer engage in whaling in the Antarctic, but Japan has plans to return this year. Video provided by Newsy
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