Carl Soileau’s chair looks comfortable, but at sea it becomes the hot seat. As the drill operator on the Pride Portland oil-exploration rig, he sits in a shatterproof glass and steel-mesh cage, in a captain’s seat perched above an opening through which the rig will eventually reach down thousands of feet to search for oil and gas reserves.

As the industry looks farther afield for the remaining large reserves of oil and gas, rigs like the Amethyst-class ones built in Portland adapt to the challenge. The most advanced drill ships have managed to complete exploratory wells in almost 10,000 feet of water. But companies have thus far only been able to bring up oil from seas as deep as 7,500 feet.

The unique design of the Amethyst rigs utilizes the inside of one platform leg to create additional storage for dozens of 60-foot lengths of pipe that encase the drill. (The steel honeycomb into which the 10-ton pipes fit was formed at Cianbro’s fabrication yard in Pittsfield and then trucked to Portland.) The design equips the comparatively small rigs to drill in more than 5,000 feet of water. They can send a drill bit an additional two miles beneath the seabed.

“Deep-water drilling is like space exploration,” said Bob Tippee, editor of the Houston-based Oil & Gas Journal. “It is very challenging, very technology-centered activity.”

Most of the current deep-water drilling activity is off Brazil, West Africa and at the outer extreme of the Gulf of Mexico. Companies like Maritima and Petrobras in Brazil have been leaders in developing that technology.

They have created highly automated, high-horsepower drill systems that assemble and operate 1,000-ton chains of drilling equipment strung between a rig deck and the sea floor. The rigs are not anchored to the sea floor, but satellite-guided positioning systems manage massive thrusters, two per corner, to keep the deck centered above the drill chain.

Soileau, a soft-spoken native of Lafayette, La., says his job is a combination of education, experience and intuition. Computer screens feed him countless readings: pressure, tension, speed, heat of the equipment, the water, the sub-sea geology. His gut helps him read between the lines to manage potential threats like bubbles of shallow gas trapped in the seabed, which can rapidly expand and become explosive if not diverted through special techniques.

It’s just that kind of thing, Soileau said, that drives industry standards to require years of learning all aspects of the processes on deck before taking a turn in the drill operator’s seat. Then the real homework begins.

The 48-year-old has been in the business since he was 18 and the last 25 years as a drill operator.

“It’s a lifelong school,” the Gulf Coast native said. “And you never learn it all.”