Seismic technology is arguably one of the most enabling technologies in the oil and gas industry. But it has its shortcomings.

It is expensive to acquire, particularly on land. The data take a long time to process and interpret. And the results are often ambiguous.

Finally, seismic information is great at illuminating underground structures, but it falls short of illuminating underground oil and gas.

NXT CEO and inventor George Liszicasz has developed a technology called the stress field detector (SFD) that he said can be used prior to a seismic survey to identify potential trapped fluid reservoirs below the surface. SFD is a patent-pending airborne technology that uses airborne gravitational measurements to identify these reservoirs. The tool is flown in a jet at 3,000 m (10,000 ft) traveling 470 km/hr (285 mph). The surveys cost a fraction of what a seismic survey would cost, can be done 90% faster than a seismic survey, and cause no environmental disturbance.

Unlike traditional gravity measurements, which measure gravity magnitude, and gravity gradiometers, which measure the difference in density magnitude from one location to another, Liszicasz maintains that SFD responds to changes in the orientation of Earth’s gravity field caused by subsurface stress.

“SFD has to be in motion,” he said. “It couples directly with the perturbations or the anomalies in the subsurface. It does not respond to the total magnitude of the field; it only responds to changes in the gravity field.”

The key to the technology is fluid’s inability to transmit shear. “You can cut rocks, and you can tear rocks, and you can apply forces from different angles,” he said. “But you can’t take a pair of scissors and cut your coffee.”

The technology was developed when Liszicasz was working on a pyroelectric material that could be used in pacemakers to harness the patient’s body heat to power the device. “I solved that problem, but in the meantime I made this discovery, and I forgot all about the other one,” he said.

He removed most of the seats in his van to house the system and drove around the US and Canada trying out his method in different geological environments – reef systems in Michigan, Austin chalk formations in Texas, salt domes in Louisiana, overthrust faults in the foothills, and overpressured reservoirs in Wyoming. Ultimately, he created a library of the tool’s responses to these varying geologic settings.

The next step was to swap the van for the jet. NXT did its first test flight in 1997 and after a lengthy R&D process began offering SFD as a commercial service in 2006.

Its first jobs were in Canada, both in conventional plays and in the Horn River basin shale play. Since then NXT has gone international and is currently working in Mexico and Pakistan, among other places.

Case studies abound. One survey led to the discovery of a 180-MMbbl field in Colombia, Liszicasz said. “The client was shooting a 3-D survey over the entire block. For [US] $500,000 we could tell them where to focus their activities in stage 1 of the exploration cycle.

“Technologies like airborne magnetics and gravity can map basin architecture; 2-D reconnaissance seismic can identify traps. We find trapped fluids. That’s what E&P companies are looking for.”

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