It started with a young man’s promise. Inspired by his bride-to-be’s dexterity with a dowsing rod, Franz Van de Kop boldly announced that someday he would build her an electronic version to snoop out aquifers.

Fast-forward several years, and Van de Kop has kept his promise to wife Bridget and has developed a tool that functions as a direct hydrocarbon indicator in the process. Called the EM Locator, the system consists of a battery-operated source that sends pulses into the ground with electrodes or a loop. The return signals are collected by a sensor, amplified, digitized, and transferred to a laptop for further processing. It can be controlled from a vehicle or on the ground.

The concept behind EM Locator is that the pulses cause liquid molecules in the subsurface to generate a charge. This in turn creates an electromagnetic (EM) wavelet that returns to the surface with enough voltage to be picked up by the sensor.

Van de Kop said that, in addition to impressing his wife, his inspiration to build the system came from a lifelong quest to design and improve equipment. But for many years the dream had to be put on the back burner while he worked 60-hour weeks in the oil and gas industry. “After I started working 40 hours a week for the government, I started investigating possibilities and building the system,” he said. “Every year we got another 1,000 ft (305 m) in depth. I knew it was working.”

He received a patent in 2001, and the couple has spent the past several years proving the concept. It initially was designed to find aquifers, but other uses became apparent over time. “When we exhibited at the SEG (Society of Exploration Geophysicists) and AAPG (American Association of Petroleum Geologists), they said, ‘We’re not interested in finding water; we want to find oil and gas,’” he said. “We had been testing close to an abandoned well, and we found a faint signature that we’d never seen before. We got the logs from the well, and at practically the same depth there was a layer of gas. We were delighted.”

Further testing on public land near Denbury’s acreage confirmed that the new signature was indeed natural gas, and after continued tests, the system now can identify oil, gas, brine water, freshwater, and even the presence of underground caves.

As with any unusual concept, convincing a black box-shy industry that this really works has not been easy. “The first couple of years, people looked at us as if we were from Mars,” Van de Kop said. “But now it’s been proven without any doubt.”

Remarkably, it was only recently that he learned how the tool worked. “My background is in electrical engineering, so I didn’t have the physics training to understand what was happening with the EM and the non-solids.” A gentleman at a trade show finally explained the physics behind the measurement to him.

The Van de Kops have taken the EM Locator concept as far as they plan to. Increasing the size of the power source would increase the depth of investigation, but that would come at a price. “This is a comfortable weight for us to carry,” he said. “A bigger power source would weigh 80 or 90 lb. The geophysical companies have their field hands, but in this case, we are the field hands.”

So the hope is to find a company interested in purchasing the technology and the patent. The Van de Kops only have one prototype, but larger versions could be used to search for deeper oil and gas pockets, and smaller versions that would fit in a backpack could be used to find aquifers in countries desperate for water. A few companies have expressed interest, but they still are waiting for one to step forward.

“We’ve never given up,” Van de Kop said. “We’ve had a marvelous time.”