Seismic Course in Suez Canal University-SEG-SCU

SEG SCU is honored to introduce one of the strongest seismic courses lectured by two of the brightest names in this field :

Dr/ Hatem Farouk Ewida - the Land Manager for BP Egypt
Dr/ Ali Bakr - the Regional Exploration Manager IPR Group

hurry up!
limited Seats!

for more info:
go to our booth
call : 01117759616

Keep visiting thegeoscienceforum.blogspot.com

Scientists detect seismic signals produced by tornado activity

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

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.

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.

"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 the Earth and gain a better understanding of seismic forces. 

More details on the experiment are available at newsinfo.iu.edu/news/page/normal/18612.html. 

Keep visiting thegeoscienceforum.blogspot.com

Oxygen detected in atmosphere of Saturn’s Moon Dione

LOS ALAMOS, New Mexico, March 2, 2012—Los Alamos National Laboratory scientists and an international research team have announced discovery of molecular oxygen ions (O2+) in the upper-most atmosphere of Dione, one of the 62 known moons orbiting the ringed planet. The research appeared recently in Geophysical Research Letters and was made possible via instruments aboard NASA’s Cassini spacecraft, which was launched in 1997.

Dione—discovered in 1684 by astronomer Giovanni Cassini (after whom the spacecraft was named)—orbits Saturn at roughly the same distance as our own moon orbits Earth. The tiny moon is a mere 700 miles wide and appears to be a thick, pockmarked layer of water ice surrounding a smaller rock core. As it orbits Saturn every 2.7 days, Dione is bombarded by charged particles (ions) emanating from Saturn’s very strong magnetosphere. These ions slam into the surface of Dione, displacing molecular oxygen ions into Dione’s thin atmosphere through a process called sputtering.

Molecular oxygen ions are then stripped from Dione’s exosphere by Saturn’s strong magnetosphere.

A sensor aboard the Cassini spacecraft called the Cassini Plasma Spectrometer (CAPS) detected the oxygen ions in Dione’s wake during a flyby of the moon in 2010. Los Alamos researchers Robert Tokar and Michelle Thomsen noted the presence of the oxygen ions.

“The concentration of oxygen in Dione’s atmosphere is roughly similar to what you would find in Earth’s atmosphere at an altitude of about 300 miles,” Tokar said. “It’s not enough to sustain life, but—together with similar observations of other moons around Saturn and Jupiter—these are definitive examples of a process by which a lot of oxygen can be produced in icy celestial bodies that are bombarded by charged particles or photons from the Sun or whatever light source happens to be nearby.”

Perhaps even more exciting is the possibility that on a moon with subsurface water, such as Jupiter’s moon Europa, molecular oxygen could combine with carbon in subsurface lakes to form the building blocks of life. Future missions to Europa could help unravel questions about that moon’s habitability.

Two sensors aboard Cassini built by Los Alamos National Laboratory are expected to come into play beginning later this month, and again in April and May, when the Cassini spacecraft flies by the moon Enceladus. The moon is one of the brightest objects in our solar system, reflecting back nearly all of the sunlight that strikes it, thanks to a shimmering surface of snowy ice crystals. The moon also unleashes plumes of material from its south polar region. Los Alamos’ ion-beam spectrometer and ion-mass spectrometer may help answer key questions about the composition of these plumes.

The research can be found at: http://www.agu.org/journals/gl/gl1203/2011GL050452/

About Los Alamos National Laboratory

Los Alamos National Laboratory, a multidisciplinary research institution engaged in strategic science on behalf of national security, is operated by Los Alamos National Security, LLC, a team composed of Bechtel National, the University of California, The Babcock & Wilcox Company, and URS for the Department of Energy's National Nuclear Security Administration.

Los Alamos enhances national security by ensuring the safety and reliability of the U.S. nuclear stockpile, developing technologies to reduce threats from weapons of mass destruction, and solving problems related to energy, environment, infrastructure, health, and global security concerns.

About the Cassini-Huygens mission

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency, and the Italian Space Agency. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini plasma spectrometer team and the ion and neutral mass spectrometer team are based at Southwest Research Institute, San Antonio.

Keep visiting thegeoscienceforum.blogspot.com