Tuesday, December 10, 2013
By JONATHAN FAHEY The Associated Press
(Continued from page 1)
A worker monitors water pumping pressure and temperature at a hydraulic fracturing and extraction site in western Colorado. Hydraulic fracturing is the practice of injecting water, sand and chemicals to help access oil and gas deposits.
The Associated Press
This technology is used by the drilling operator to drill into the Marcellus shale at a well site in Washington, Pa.
The Associated Press
SMART DRILLS, RIGS THAT CAN WALK
But even after drillers figured out how to find oil and gas deep offshore and in onshore source rock, they still needed to develop technology that would make it economical.
At the tip of every oil or gas drill is a rotating mouth of sharp teeth that chews through rock. In the past, these drill bits could only dig straight down. Now they are agile enough to find and follow narrow horizontal seams of rock.
The drilling-services company Baker Hughes has designed a bit that can change directions underground, without having to be drawn back up to the surface, reducing drilling time by as much as 40 percent.
Behind the drill bit, attached to a long line of steel known as the "drill string," is an array of sensors. The sensors bombard rock with subatomic particles and measure the gamma radiation that bounces back. They assess how easily electricity flows through the rock and underground fluids. They analyze the magnetism of the rock and how it vibrates -- both up and down and side to side -- while drilling.
"To the layman, it looks like dumb iron, but you'd be shocked about what's inside," says Art Soucy, president of global products and services at Baker Hughes.
All this information is sent to engineers via fiber-optic cables. They run the information through supercomputers as powerful as 30,000 laptops to create a picture of the earth thousands of feet below the surface.
The people analyzing this data -- and even directing the drill bits -- are often sitting hundreds of miles away. Shell's Pennsylvania drilling operations are directed from a center in Houston, where experienced drillers monitor the progress at several sites across the country from a single room.
And when the drilling is done, the rig itself can "walk" a hundred feet or so to another location and start drilling again. In the past, rigs had to be taken down and reassembled, which could take days. New rigs are built on sliding "shoes" that allow hydraulic lifts to shuffle the rig forward in short steps.
"It has made possible things that were unthinkable 10 years ago," says Claudi Santiago, managing director at First Reserve Corp., a private-equity firm that invests in energy companies.
Now, drillers are finding oil faster than the world is using it. At the end of 2001, the industry had enough "proved oil reserves" to satisfy world demand for 45 years, according to BP's annual statistical review, a closely watched study. By the end of 2011 that had grown to 51 years -- even though a decade's worth of oil had been used and daily demand had grown 14 percent. And "proved reserves" refers to oil that can be economically tapped using today's technology. Tomorrow's methods could yield even more.
This is good news for a global economy that remains dependent on fossil fuels, but it's terrifying to climate scientists.
"If we're willing to go down this road of squeezing whatever petroleum we can out of the earth, we can easily get carbon dioxide levels up to unfathomable levels and put in motion what would be dramatic or catastrophic changes in our climate system," says Michael E. Mann, a geophysicist and director of the Earth System Science Center at Penn State University.