I don't have the expertise to evaluate these two articles, but I found them interesting. The first from :
http://www.geotimes.org/june03/NN_gulf.html
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Raining hydrocarbons in the Gulf
Below the Gulf of Mexico, hydrocarbons flow upward through an intricate network of conduits and reservoirs. They start in thin layers of source rock and, from there, buoyantly rise to the surface. On their way up, the hydrocarbons collect in little rivulets, and create temporary pockets like rain filling a pond. Eventually most escape to the ocean. And, this is all happening now, not millions and millions of years ago, says Larry Cathles, a chemical geologist at Cornell University.
"We're dealing with this giant flow-through system where the hydrocarbons are generating now, moving through the overlying strata now, building the reservoirs now and spilling out into the ocean now," Cathles says.
He's bringing this new view of an active hydrocarbon cycle to industry, hoping it will lead to larger oil and gas discoveries. By matching the chemical signatures of the oil and gas with geologic models for the structures below the seafloor, petroleum geologists could tap into reserves larger than the North Sea, says Cathles, who presented his findings at the meeting of the American Chemical Society in New Orleans on March 27.
This canvas image of the study area shows the top of salt surface (salt domes are spikes) in the Gas Research Institute study area and four areas of detailed study (stratigraphic layers). The oil fields seen here are Tiger Shoals, South Marsh Island 9 (SMI 9), the South Eugene Island Block 330 area (SEI 330), and Green Canyon 184 area (Jolliet reservoirs). In this area, 125 kilometers by 200 kilometers, Larry Cathles of Cornell University and his team estimate hydrocarbon reserves larger than those of the North Sea. Image by Larry Cathles.
Cathles and his team estimate that in a study area of about 9,600 square miles off the coast of Louisiana, source rocks a dozen kilometers down have generated as much as 184 billion tons of oil and gas — about 1,000 billion barrels of oil and gas equivalent. "That's 30 percent more than we humans have consumed over the entire petroleum era," Cathles says. "And that's just this one little postage stamp area; if this is going on worldwide, then there's a lot of hydrocarbons venting out."
According to a 2000 assessment from the Minerals Management Service (MMS), the mean undiscovered, conventionally recoverable resources in the Gulf of Mexico offshore continental shelf are 71 billion barrels of oil equivalent. But, says Richie Baud of MMS, not all those resources are economically recoverable and they cannot be directly compared to Cathles' numbers, because "our assessment only includes those hydrocarbon resources that are conventionally recoverable whereas their study includes unconventionally recoverable resources." Future MMS assessments, Baud says, may include unconventionally recoverable resources, such as gas hydrates.
Of that huge resource of naturally generated hydrocarbons, Cathles says, more than 70 percent have made their way upward through the vast network of streams and ponds, venting into the ocean, at a rate of about 0.1 ton per year. The escaped hydrocarbons then become food for bacteria, helping to fuel the oceanic food web. Another 10 percent of the Gulf's total hydrocarbons are hidden in the subsurface, representing about 60 billion barrels of oil and 374 trillion cubic feet of gas that could be extracted. The remaining hydrocarbons, about 20 percent, stay trapped in the source strata.
Driving the venting process is the replacement of deep, carbonate-sourced Jurassic hydrocarbons by shale-sourced, Eocene hydrocarbons. Determining the ratio between the younger and older hydrocarbons, based on their chemical signatures, is key to understanding the migration paths of the oil and gas and the potential volume waiting to be tapped. "If the Eocene source matures and its chemical signature is going to be seen near the surface, it's got to displace all that earlier generated hydrocarbon — that's the secret of getting a handle on this number," Cathles says.
Another important key to understanding hydrocarbon migration is "gas washing," Cathles adds. A relatively new process his research team discovered in the Gulf work, gas washing refers to the regular interaction of oil with large amounts of natural gas. In the northern area of Cathles' study area, he estimates that gas carries off 90 percent of the oil.
Ed Colling, senior staff geologist at ChevronTexaco, says that identifying the depth at which gas washing occurs could be extremely useful in locating deeper oil reserves. "If you make a discovery, by back tracking the chemistry and seeing where the gas washing occurred, you have the opportunity to find deeper oil," he says.
Using such information in combination with the active hydrocarbon flow model Cathles' team produced and already existing 3-D seismic analyses could substantially improve accuracy in drilling for oil and gas, Colling says. ChevronTexaco, which funds Cathles' work through the Global Basins Research Network, has been working to integrate the technologies. (Additional funding comes from the Gas Research Institute.)
"All the players are looking for bigger reserves than what's on shore," Colling says. And deep water changes the business plan. With each well a multibillion dollar investment, the discovery must amount to at least several hundred million barrels of oil and gas for the drilling to be economic. Chemical signatures and detailed basin models are just more tools to help them decide where to drill, he says.
"A big part of the future of exploration is being able to effectively use chemical information," Cathles says. Working in an area with more oil by at least a factor of two than the North Sea, he says he hopes that his models will help companies better allocate their resources. But equally important, Cathles says, is that his work is shifting the way people think about natural hydrocarbon vent systems — from the past to the present.
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and the next, from a recent futurepundit post:
http://www.futurepundit.com/archives/002981.html#002981
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Shell Oil Shale Extraction Technology Economically Viable?
The development of an economically viable way to extract oil from oil shale would put a ceiling on oil prices and would extend the oil era by decades. It would also increase the odds of significant global warming. Well, in light of all that a variety of media outlets are reporting that Shell Oil thinks it can produce oil from oil shale at $30 per barrel using an in situ process where the shale is cooked without first mining it onto the surface.
They don't need subsidies; the process should be commercially feasible with world oil prices at $30 a barrel. The energy balance is favorable; under a conservative life-cycle analysis, it should yield 3.5 units of energy for every 1 unit used in production. The process recovers about 10 times as much oil as mining the rock and crushing and cooking it at the surface, and it's a more desirable grade. Reclamation is easier because the only thing that comes to the surface is the oil you want.
And we've hardly gotten to the really ingenious part yet. While the rock is cooking, at about 650 or 750 degrees Fahrenheit, how do you keep the hydrocarbons from contaminating ground water? Why, you build an ice wall around the whole thing. As O'Connor said, it's counterintuitive.
Shell is just now moving onto the next stage to decide by 2010 whether their process is commercially feasible.
Shell has received approval from Rio Blanco County, state and federal officials to conduct a $50 million, two- to four-year study of a groundwater freezing process, said Jill Davis.
“We’re still looking to decide if we’ll move on to commercial production by the end of the decade,” she said. “It’s been promising, so we want to take it to the next level with an environmental test of our ‘freeze wall’ process.”
Refrigerants, such as ammonia dioxide, are circulated through underground pipes to freeze the groundwater and earth to keep groundwater out of an oil-shale formation.
“We’ve tested the process in a circular pattern and this will be a football field-shaped rectangle in an area more like where commercial production could happen,” she said.
Some estimates for the amount of oil in shale range as high as 1 trillion to 1.8 trillion barrels. Assume that 1 trillion barrels could be extracted. The United States currently uses about 20.5 million barrels per day which is about a quarter of current world oil demand. World oil demand is projected to rise to 119 million barrels per day by 2025 or about a 50% increase. Suppose we take that 119 million barrel figure and round it off to 120 million barrels. Also let us assume that oil shale could yield 1 trillion barrels of oil. That oil shale would satisfy total world oil demand by this equation: 1,000,000 million barrels/(365 days per year times 120 million barrels per day) which equals only 22 years at the projected year 2025 consumption rate. Even oil shale can delay the end of the oil era by a couple of decades. Still, we could use those decades to develop technologies to lower the cost of nuclear and photovoltaic solar power.
A recent RAND corporation report with lead author James Bartis argues the US government should add oil shale to its energy research portfolio.
Since the future prospects for oil shale remain uncertain, the RAND report recommends that the federal government refrain from major investments in oil shale development until the private sector is prepared to commit its technical, management and financial resources. However, the report recommends a few low-cost efforts that can begin in the near future to move oil shale development forward.
The report by the RAND Environment, Energy and Economic Development program says that between 500 billion and 1.1 trillion barrels of oil are technically recoverable from high-grade oil shale deposits located in the Green River geological formation, covering parts of Colorado, Utah and Wyoming.
The mid-point of the RAND estimate – 800 billion barrels – is three times the size of Saudi Arabia's oil reserves. This is enough oil to meet 25 percent of America's current oil demand for the next 400 years.
The benefits of a competitive oil shale industry are substantial. For an output of 3 million barrels per day, the study estimates direct economic benefits of about $20 billion per year. Federal, state and local governments would receive about half of this amount in the form of lease payments, royalties and taxes.
Production at 3 million barrels per day also could likely cause oil prices to fall by 3 to 5 percent, saving American oil consumers roughly $15 billion to $20 billion annually, according to the report. A multimillion-barrel per day oil shale industry could also create several hundred thousand jobs in the United States.
The in situ process may avoid many of the environmental problems that arise from oil shale mining.
Another technical development that has been taking place involves heating the oil shale while it is still in the ground – a process called in-situ conversion. Mining is not required. Instead, electric heating elements are placed in bore holes, slowly heating the shale oil deposit. The released liquids are gathered in wells specifically designed for that purpose.
In contrast to surface mining, in-situ conversion does not permanently modify land surface topography and may be significantly less damaging to the environment. Small field tests conducted by Shell Oil involving an in-situ approach appear promising. While larger scale tests are needed, Shell anticipates that this method may be competitive with crude oil priced below $30 per barrel. RAND has not developed an independent estimate of the price level needed to make in-situ conversion competitive.
On the environmental side, adverse land and ecological impacts will accompany oil shale development no matter which approach is used. Oil shale production will also result in airborne and greenhouse gas emissions that could severely limit oil production levels.
Colorado has the largest oil shale deposits and some deposits have more oil per ton of rock.
Steve Wiig, geologist for the Rock Springs BLM office, said Wyoming oil shale, on average, would produce 15 to 30 gallons of oil per ton of oil shale rock. He said the Colorado and Utah deposits could produce 30 to 40 gallons, with some sites capable of producing 60 gallons of oil per ton of oil shale.
Another company says it can produce oil from shale even more cheaply using a more conventional approach.
For example, one of the star witnesses of Gibbons' hearings was Jack Savage, president of Utah-based Oil-Tech Inc. He said the company is ready to start cooking oil out of shale with a retort it has built near Vernal, Utah.
"We have been working on this for 15 years," Savage said. "Now we're ready to go."
Savage, once president of companies that manufactured golf bags and other sporting goods, said he can turn shale into oil for $10 to $22 a barrel, depending on market conditions. Savage pushed for an accelerated federal leasing program, but he's already leased 38,000 acres of state land in Utah and says he's working on a research-and-development bid to continue work on his project.
The biggest problem with mining oil shale comes as a result of heating oil shale rock. The rock expands in size and then can't just get put back where it was excavated.
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