Featured Research

from universities, journals, and other organizations

Scientists detect seismic signals from tornado

Date:
March 8, 2012
Source:
Indiana University
Summary:
A geophysical experiment detected unusual seismic signals associated with tornadoes that recently struck regions across the Midwest -- information that may have value for meteorologists studying the atmospheric activity that precedes tornado disasters.

A graphic shows the location of seismographs in eastern Missouri and southern Illinois and the path of the tornado that struck Harrisburg, Ill., on Feb. 29.
Credit: Image courtesy of Indiana University

An Indiana University geophysical experiment detected unusual seismic signals associated with tornadoes that recently struck regions across the Midwest -- information that may have value for meteorologists studying the atmospheric activity that precedes tornado disasters.

Related Articles


The experiment by IU researchers involves deployment of more than 100 state-of-the-art digital seismographs in a broad swath of the U.S. midcontinent. One of the twisters that struck southeastern Missouri and southern Illinois on Feb. 29 passed through the seismic detection array.

"In examining the seismograms, we recorded unusual seismic signals on three of our stations in southern Illinois," said Michael Hamburger, professor in the department of geological sciences at IU Bloomington and one of the researchers conducting the experiment.

"The seismograms show a strong, low-frequency pulse beginning around 4:45 a.m. on Feb. 29. Our preliminary interpretation, based on other seismic records of tornadoes, suggests that we were recording not the tornado itself, but a large atmospheric pressure transient related to the large thunderstorms that spawned the tornadoes."

The seismographs that detected the pulse are near Harrisburg, Ill., a town of 9,000 where a pre-dawn twister caused extensive damage, killed six people and injured about 100 more.

IU researchers initially feared that some of the instruments might be damaged by the storm, setting back a National Science Foundation-funded project that included the investment of hundreds of thousands of dollars and months of effort. But when principal investigator Gary Pavlis, an IU professor of geological sciences, checked the digital recordings of the Illinois stations on Feb. 29, he found they were still alive and streaming data. As he checked further, he discovered the strange "tornado seismograms" that were recorded on seismographs near Harrisburg.

Hamburger said a seismic pressure gradient associated with the tornado produced a slow, minute tilting of the seismograph that lasted for several minutes. He said this sort of pressure-related signal may help scientists better understand atmospheric activity that takes place right before tornadoes touch down. The IU researchers are working with colleagues at the University of California San Diego to try to compare recordings with other tornado-related signals and to dig deeper into the analysis.

While seismographs have been known to detect seismic activity related to tornadoes, it is highly unusual to have state-of-the-art digital instruments recording information in such close proximity to a tornado, the researchers say.

The IU seismic experiment, dubbed "OIINK" for its geographic coverage in parts of the Ozarks, Illinois, Indiana and Kentucky, includes the positioning of 120 seismometers to study earthquakes and geological structure in a key area of North America. Installation of the instruments began last summer. They are recording thousands of earthquakes from the study area and around the world, as well as nearby mining and quarry explosions.

The $1.3 million, four-year undertaking is part of the NSF's EarthScope program, which seeks to cover the entire U.S. with a grid of detection devices for the purpose of better understanding seismic activity and predicting earthquakes. Researchers liken EarthScope to "an upside-down telescope" that allows them to look into Earth and gain a better understanding of seismic forces.


Story Source:

The above story is based on materials provided by Indiana University. Note: Materials may be edited for content and length.


Cite This Page:

Indiana University. "Scientists detect seismic signals from tornado." ScienceDaily. ScienceDaily, 8 March 2012. <www.sciencedaily.com/releases/2012/03/120308101327.htm>.
Indiana University. (2012, March 8). Scientists detect seismic signals from tornado. ScienceDaily. Retrieved April 18, 2015 from www.sciencedaily.com/releases/2012/03/120308101327.htm
Indiana University. "Scientists detect seismic signals from tornado." ScienceDaily. www.sciencedaily.com/releases/2012/03/120308101327.htm (accessed April 18, 2015).

Share This


More From ScienceDaily



More Earth & Climate News

Saturday, April 18, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Planet Defence Conference Tackles Asteroid Threat

Planet Defence Conference Tackles Asteroid Threat

AFP (Apr. 17, 2015) Scientists gathered at a European Space Agency (ESA) facility outside Rome this week for the Planetary Defence Conference 2015 to discuss how to tackle the potential threat from asteroids hitting Earth. Duration: 00:54 Video provided by AFP
Powered by NewsLook.com
Gulf Scarred, Resilient 5 Years After BP Spill

Gulf Scarred, Resilient 5 Years After BP Spill

AP (Apr. 17, 2015) Five years after the Deepwater Horizon spill in the Gulf of Mexico, splotches of oil still dot the seafloor and wads of tarry petroleum-smelling material hide in pockets in the marshes of Barataria Bay. (April 17) Video provided by AP
Powered by NewsLook.com
Boeing's Autonomous Underwater Vehicles (AUV) Echo Ranger

Boeing's Autonomous Underwater Vehicles (AUV) Echo Ranger

Scuba Diving (Apr. 16, 2015) Seventy years after its service in World War II, NOAA, working with private industry partners, has confirmed the location and condition of the USS Independence. Resting upright in 2,600 feet of water off California’s Farallon Islands, the aircraft carrier’s hull and flight deck are clearly visible in sonar images, with what appears to be a plane in the carrier’s hangar bay. Video provided by Scuba Diving
Powered by NewsLook.com
California Drought Renews Thirst for Desalination Plants

California Drought Renews Thirst for Desalination Plants

Reuters - US Online Video (Apr. 16, 2015) As California&apos;s water crisis deepens, a one billion dollar desalination plant is set to go on-line near San Diego. Nathan Frandino reports. Video provided by Reuters
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