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Petroleum engineering

field of engineering concerned with the activities related to the production of hydrocarbons, which can be either crude oil or natural gas

Petroleum engineering is a field of engineering concerned with the activities related to the production of hydrocarbons, which can be either crude oil or natural gas.

QuotesEdit

 
The oil and gas business is really a water-handling business. The pore spaces, or tiny holes, in the rock remain filled with these ancient oceans, so when we drill wells today that water is produced to the surface. ~ Scott Tinker
 
When Hubbert presented the results at the Amsterdam conference, “it was very well received by the highest level technical people,” he recalled, “accepted completely, with no significant criticism.” After this vote of confidence, Shell organized training sessions on the new analysis for its field engineers. When it came time for the first course, Willis was away so Hubbert gave it himself. “What I discovered was that the theoretical argument was having no effect whatever on these men,” Hubbert recalled. The engineers were absolutely sure that the fractures were horizontal. Every article, every ad on fracking showed fractures oriented that way. They had been “completely brainwashed,” Hubbert thought. “They didn’t have any real evidence, but they’d been so thoroughly indoctrinated on this thing that they knew damned well these fractures were horizontal.” It mattered, because if they didn’t understand the forces at work, they couldn’t control it precisely. The technique would remain more art than science. ~ Mason Inman
  • Rex Buchanan, interim director of the Kansas Geological Survey, was watching a Kansas City Royals game in September 2014 when his cell phone started buzzing with alerts from the USGS. Tremors were shaking south-central Kansas near the state's border with Oklahoma. This was not a surprise, because more than 100 earthquakes had visited Kansas during that year, up from an average of one every two years. But the tremors were growing stronger and soon reached magnitude 4.2. Kansas governor Sam Brownback convened an induced-seismicity task force to evaluate the quakes. The task force, chaired by Buchanan, recommended restricting injection volumes within five seismic zones across two counties.
    How were Kansas officials able to reach a consensus? “I don't think we could come up with any other explanation,” Buchanan says. “You see a level of activity like we saw: a dramatic, dramatic increase, and in almost exactly the place where the really large-volume wells are going in—and where you see the same correlation in Oklahoma. It's pretty hard to come to any other conclusion.” He adds that he and his colleagues had the benefit of watching science and regulations develop in Ohio, Texas and Oklahoma. So far the measures Kansas took seem to have had an impact. “Certainly our activity has been down lately,” he says, in terms of both earthquake rates and size. “But I have pressed people real hard not to take the approach that this is some sort of problem solved, because it's not.”
  • “Scores of papers on injection-induced earthquakes were published in the geophysical literature in the following 40-plus years, and the problem was well understood and appreciated by seismologists,” says Bill Ellsworth, a Stanford University geophysicist who launched his career at the USGS while the Rangely experiment was under way. He believes professional skepticism slowed the formation of a consensus. “There were a lot of doubts expressed by very good petroleum engineers that [earthquakes caused by injection wells] were even possible,” he says. “Knowledge of the whole physical process was either lost or had not been effectively communicated to a broad community.”
  • To many Oklahomans, it is clear that that risk has risen sharply. Data back up their experiences. The earthquake rate in the state has grown at an astounding pace. In 2013 the state recorded 109 quakes of magnitude 3 and greater. The following year the number jumped to 585, and in 2015 it reached 890.
    The escalation prompted two unusual warnings jointly issued by the USGS and the OGS in October 2013 and May 2014. Seismologists stated that Oklahoma had a significantly increased chance of seeing a damaging magnitude 5.5 temblor. “It was the first time I think we'd ever issued an earthquake advisory east of the Rockies,” says Robert Williams, the USGS central and eastern U.S. coordinator for earthquake hazards.
  • Over the past few years, fracking fever has swept through several European nations, including Denmark, Lithuania, Romania and especially Poland, which has seen more shale exploration than any other nation on the continent. Fracking might help to boost gas production in Europe at a time when it is facing a sharp decline. Older gas fields in the North Sea are running out, as are deposits in Germany, Italy and Romania. The disappointing output has increased Europe's dependence on imported gas, mainly from Russia.
  • The results in Poland to date indeed have been disappointing,” concedes geologist Scott Stevens of ARI. He says that the main reason for the unproductive wells was “extremely high” stresses in the rock, which makes fracking less effective. “There was no way that the exploration companies could know that in advance,” he notes. Nonetheless, he argues, “It is too soon to dismiss Poland's extensive shale potential.” Given the limited available data, he does not see a reason to revise ARI's estimate.
  • By the time Shell tasked Hubbert with explaining how fracking worked, “we had the records of several thousand fracturing jobs, with varying degrees of reliability in their data,” he recalled. “We had to smoke out useful information.”
  • When Hubbert presented the results at the Amsterdam conference, “it was very well received by the highest level technical people,” he recalled, “accepted completely, with no significant criticism.” After this vote of confidence, Shell organized training sessions on the new analysis for its field engineers. When it came time for the first course, Willis was away so Hubbert gave it himself. “What I discovered was that the theoretical argument was having no effect whatever on these men,” Hubbert recalled. The engineers were absolutely sure that the fractures were horizontal. Every article, every ad on fracking showed fractures oriented that way. They had been “completely brainwashed,” Hubbert thought. “They didn’t have any real evidence, but they’d been so thoroughly indoctrinated on this thing that they knew damned well these fractures were horizontal.” It mattered, because if they didn’t understand the forces at work, they couldn’t control it precisely. The technique would remain more art than science.
  • In Shell’s Bellaire lab, one of the nation’s best-funded research facilities, sat the contraption Willis had assembled at home over the weekend. It was a goldfish bowl, filled with liquid Knox gelatin and some plaster in it. Willis had used the gelatin to simulate rock—appropriate, given Hubbert’s work on laws of scaling—and had stuck an Alka-Seltzer bottle in the middle of it to mimic a well. He’d put the liquid gelatin in the fridge and let it set, then pulled out the bottle. Then he’d used a baster to pump a slurry of plaster of Paris down the hole, filling it until the plaster began to push its way into the gelatin, forming fractures. As their theory predicted, the fractures were vertical.
    Although Willis’s setup was kludged together, Hubbert immediately realized it was what they needed to win over the field engineers: a clear demonstration. They’d have an opportunity to make their case at an internal Shell conference in early 1956, in several weeks’ time. They got to work on building a larger version of the model. To replace Willis’s goldfish bowl, Hubbert scoped out bigger aquariums on sale at local shops.
    At the Shell conference, Hubbert and Willis explained their experiment and showed the plaster casts, first from one angle, with the fractures flaring out from either side of the well. Then they rotated the cast, so the audience could see that the fractures were thin and sharp, like a knife’s blade. And of course, they were undoubtedly vertical.
    Within a week of this demonstration, field engineers began sending in data they’d collected after fracturing wells. Some of them had put rubber plugs down wells to form an impression of the wall. Others sent cameras down the hole. This field data showed the fractures were indeed vertical. The theory was right—and finally the engineers believed it. Willis’s contraption “had a magical effect,” as Hubbert put it. “It made Christians out of these people.”
  • Unlike Ahab (spoiler alert), Drake wasn’t destroyed by his discovery — at least not instantly. But although he was the first to engineer a successful oil-drilling system, lining his well with pipe to keep it from caving in, he never patented the method, and the money he’d made when he struck oil soon dried up.
    A century later, TIME referred to him as “a sickly, bearded failure of a man in a stovepipe hat” in a story that nonetheless acknowledged that “[t]hough Discoverer Drake wound up virtually penniless and forgotten, his find opened the scramble for oil across the land,” inspiring a legion of oil prospectors to chase what had become, by 1959, “the greatest single source of wealth in America.”
  • We currently import around half of our gas needs, but by 2030 that could be as high as 75%. That's why we're encouraging investment in our shale-gas exploration so we can add new sources of home-grown supply.
  • With that gas and oil, however, come vast quantities of very salty water. “The oil and gas business is really a water-handling business,” says Scott Tinker, Texas's state geologist and director of the University of Texas at Austin's Bureau of Economic Geology. The water comes from the same rocks as the oil and gas. All three are remnants of ancient seas that heat, pressure and time transformed. “The pore spaces, or tiny holes, in the rock remain filled with these ancient oceans, so when we drill wells today that water is produced to the surface,” Tinker says. Although the water is natural, it can be several orders of magnitude more saline than seawater and is often laced with naturally occurring radioactive material. It is toxic to plants and animals, so operators bury it deep underground to protect drinking-water supplies closer to the surface.

See alsoEdit

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