It seems ExxonMobil has secret plans, apparently known only to few outside the BLM, about how to fracture tight shale beds to release natural gas.
Exxon unlocks gas: Energy giant finds key to hidden fuel but guards its plans
After shuttering its shale-oil business and pulling out of Colorado more than two decades ago, the world's biggest publicly traded energy company is quietly ramping up its presence again in the state.
Forget shale oil. This time, Exxon Mobil is going after natural gas.
The energy giant is sitting on 35 trillion cubic feet of natural gas in Colorado's Piceance Basin, enough to fuel the entire nation for almost two years.
The figure of 35 trillion cubic feet (Tcf) mentioned in the article compares with about 27 Tcf of similar "tight" gas in the Bartlett Shale beneath Ft. Worth, Texas. Current USA natural gas consumption is about 24 Tcf per year, so the article overstates the meaning of the number in terms of current and projected fuel demand. Read on. This is abotu terminology.
To unlock that "tight gas," Exxon engineers began research in 1995 to develop a new drilling technology. After a decade of hard work, the company says it has achieved a technological breakthrough that will have wide implications for the Colorado plateau.
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"There are many trillions of cubic feet of gas in tight-gas resources in the Western United States and Canada," Kris Nygaard, one of the inventors of the technology, said in the current issue of The Lamp, Exxon's shareholder magazine.
"Exxon Mobil's ability to go after tight gas is a technical breakthrough that will add significant volumes to our U.S. natural gas supply."
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Since it's a proprietary technology, few people know about it. In fact, many activists criticize Exxon for not being more open with the local community about its operations in Colorado.
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The high cost of conventional technology justifies drilling only in prolific fields with easy access to the resource. So many areas in the Piceance Basin with tight gas deposits are simply left untouched.
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In the Piceance Basin, natural gas is trapped in isolated layers, often within 20 feet of one another. To extract the maximum amount of gas, companies fracture dozens of such layers in a well.
Exxon's "multizone stimulation technology" allows drillers to frac or break open a target layer of rock and shoot holes in the well casing, all in one continuous process. The sequence begins at the deepest layer in the well and continues up to each new layer.
To further improve the recovery of gas, drillers can combine up to nine wells, with surface locations spaced 15 feet apart, on a single pad.
Unlike conventional fracturing technology that can take several weeks to complete a few high-quality fractures in a well, Exxon's new technology has treated up to 22 layers or zones in a single day, the company said.
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Apart from the U.S Bureau of Land Management, which owns 90 percent of Exxon's leased acres, few know about the company's plans. County officials don't know how much Exxon plans to spend this year or how many new people it will employ.
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Pete Kolbenschlag of the Colorado Environmental Coalition: "We are talking about thousands of wells coming to Piceance Basin. Unless oil and gas companies do a good job of community outreach, people will be resistant and skeptical to it."
The figure of 35 trillion cubic feet (Tcf) mentioned in the article compares with about 27 Tcf of similar "tight" gas in the Bartlett Shale beneath Ft. Worth, Texas. Current USA natural gas consumption is about 24 Tcf per year, so the article overstates the meaning of the number in terms of current and projected fuel demand.
The quantities of natural gas indicated in the article are what is known as "gas in place", i.e. all the natural gas resource estimated to be contained within a geologic unit. The technically recoverable portion of this gas (recoverable under current technology and economics) may be less than 10 percent of the total, and this lesser amount is what the U.S. Geological Survey reports as proven reserves. [The gas resource can't be counted as a proven reserve until an industry proves it can actually produce and sell the gas.] It will be interesting to see how the economics of the planned ExxonMobil operation play out as more and more liquefied natural gas becomes available on the global market.
This is an important issue - a reminder that improved technology increases natural gas (and other mineral) reserves. Thus, proven reserve quantities tend to increase somewhat with time. Pay attention to the significant differences between "resources" and "reserves".
The lesson here is to understand the terminology, and to recognize the hype surrounding claims about natural gas volumes. For example, here in New Mexico, the Raton Basin of the New Mexico and Colorado border region contains perhaps 21 Tcf of "gas in place". Nonetheless, only about 2.35 Tcf of Raton Basin natural gas -- or 11 percent of that estimate -- is recoverable under current technical and economic conditions.