University of Calgary

Furthering seismic science with a bang

UToday HomeJuly 16, 2012

Gary Margrave, centre,  a professor of geophysics in the Faculty of Science and the director of CREWES, explains the series of seismic experiments to about 40 observers, most of whom work in the oil and gas industry.Gary Margrave, centre, a professor of geophysics in the Faculty of Science and the director of CREWES, explains the series of seismic experiments to about 40 observers, most of whom work in the oil and gas industry.Dozens of observers from the oil and gas industry were on hand last week when the university’s Consortium for Research in Elastic Wave Exploration Seismology (CREWES) conducted a series of seismic experiments — including dynamite test charges — at the Rothney Astrophysical Observatory (RAO) near Priddis.

In strict compliance with safety controls, CREWES detonated a series of dynamite charges well underground as part of a detailed comprehensive charge size test, says Gary Margrave, a professor of geophysics in the Faculty of Science and the director of CREWES. He says the largest charge, two kilograms, was detonated 50 feet below the ground with absolutely no risk of damage to any property or wildlife.

He compares the experiment to finding the right sized flash for a camera to light up a dark room.

“Clearly you want the more powerful one, but the more powerful, the more they cost and the more you risk damaging infrastructure that might be around,” he says. “It’s very important to characterize the radiation pattern of dynamite.”

Other experiments conducted included testing a broad variety of seismic receivers, or geophones, as well testing to see whether the non-linear interaction between two vibrator trucks would offer an advantage.

About 40 people from the oil and gas industry travelled out to watch the experiments, including Henry Bland, who is with Halliburton, one of CREWES’ 26 industry sponsors.

“To see it firsthand is much better than to read about it in a report a month from now,” says Bland. “You really get a much better understanding of what actually happened and what the challenges were and what was practical and what was impractical.” The CREWES consortium in the Faculty of Science has been conducting experiments for more than 23 years.

“Modern seismic techniques have a certain level of technology and the CREWES consortium is trying to advance that,” says Margrave.

He says it will take a couple of years to fully analyze the data collected at this week’s experiments and it will add to about 25 graduate students’ work and ultimately benefit industry.

“CREWES tries new techniques and methods and untested algorithms, plus they invent new ones,” says Bland. “That’s really the value for anyone supporting a research group at the University of Calgary is hoping they will discover the next new thing.”