New technology = new oil.

• Author: Tyson, Ray
• Position: Oil drilling innovations

Ten billion barrels of unrecoverable North Slope crude may now be tapped by new, less expensive drilling techniques like coiled tubing.

With no more megaprojects in the hopper to help slow the tide of declining crude production at Prudhoe Bay, industry has turned its eyes toward efficient and less expensive ways of squeezing more black gold from the nation's largest oilfield.

Field operators point to the innovative use of coiled tubing as a little known but rapidly evolving technology that could revolutionize drilling operations at Prudhoe Bay, while substantially increasing the amount of oil that can be recovered from the reservoir over the long haul.

There's no doubt the last of the mammoth investments at Prudhoe Bay, the $1.6-billion GHX gas-handling project, has performed well above expectations since the first stage came on line in the fall of 1990.

That's because GHX can recycle huge volumes of reservoir gas that impede oil recovery. The project has provided incremental bursts in crude yields and kept the field from lapsing into steep decline. It also has added 800 million barrels of recoverable oil and perhaps years to the field's productive life.

But even with the benefit of GHX, as well as other so-called Enhanced Oil Recovery (EOR) projects, crude output from the Prudhoe Bay reservoir has dropped from a daily peak of 1.6 million barrels in 1988 to the current rate of just over 1 million barrels a day.

So with the cost of doing business on the rise and oil production in a natural and irreversible decline, producers conclude another GHX-type project at Prudhoe Bay just wouldn't pay off in the long run.

Nonetheless, there remains a huge and inviting target -- perhaps 10 billion barrels of crude that can't be extracted with current technologies. But it will require innovative drilling techniques to reach the many elusive pockets of oil contained within the Prudhoe Bay reservoir.

TIMELY COILED TUBING

Such well-known technological advancements as horizontal and sidetrack drilling have reduced costs and enabled producers to capture more hydrocarbons from Prudhoe Bay's shrinking oil column. More recently, an experimental drilling program using stainless steel coiled tubing is getting a lot of attention on the North Slope these days.

"I think there are a lot of things we are going to see in the next two years in terms of technology and innovation with the use of coiled tubing," declares Jim Weeks, senior vice president in charge of Arco...