Story from Michigan Tech's Tech Topics Newsletter Jan 7, 2005



Finding oil is a dicey proposition, as roller-coaster gas prices attest. But Department Chair Wayne Pennington and Research Professor Roger Turpening of the Department of Geological and Mining Engineering and Sciences hope to make it a little easier, with the help of a $750,000 grant from the U.S. Department of Energy.

The problem with finding oil, or course, is the stubborn opacity of dirt. Geophysicists do their best to overcome this through the use of seismic imaging techniques. They work like ultrasound, sending out sound waves from the surface of the earth down toward potential oil reservoirs; the waves that bounce back are interpreted at the receiving end to reveal (or not) any signs of oil. However, most undiscovered oil is very deep, so by the time these echoes come back to the surface, the data they yield can sometimes seem almost as baffling as chicken scratch.

Pennington shows an image of a reservoir near Traverse City. "It's about 4,500 feet deep," he says. "It's hard to image something carefully that's that far away."

In fact, oil companies poked several deep holes in the ground before finally hitting this 70-acre reservoir, which was once a coral reef. It has since yielded about 1 million barrels of oil worth $20 million to $30 million.

Funded by the DOE, the researchers are using those dry holes to get a lot closer to the reef with their seismic imaging equipment. They hope that this new proximity will yield much better pictures of what's down there.

Using a technique known as crosswell seismic imaging, they will lower equipment deep into two wells, one on either side of the ancient reef. One side will send out seismic waves, and the other will receive them.

This way, the scientists expect to get a much clearer view of the reef's composition. "We'll use the amplitudes of the reflected seismic waves to tell us about the characteristics of the rock and the fluids that saturate the rock," Pennington said. "Some places have gas, some have water, and some have oil, and the amplitudes of the reflected waves will vary depending on the fluid."

They don't expect to end America's oil shortage in the near future. Underground, the earth is such a complicated place that seismic imaging is always tricky. "It's a big mess down there," Turpening admits.

Pennington agrees. "There's a lot of stuff going on, and on the first try, we'll probably do something wrong."

However, once they learn from those inevitable mistakes, they will bring their improved technology to a commercial drilling site and use it to help narrow down where the oil is and where it isn't.

"This will help find better ways to characterize the interior of these reefs," Turpening said. "We'll get a lot clearer image."


Back To News page

Department of Geological & Mining Engineering & Sciences
Michigan Technological University
1400 Townsend Drive - Houghton, MI 49931-1295
(906) 487-2531