Sweden to Test Theory That Earth Has Unlimited Supply of Oil, Gas

It was one of planet Earth’s most violent encounters.

About 360 million years ago, a giant meteor slammed into the ground north of here with such force that it apparently shattered the crust of the Earth to a depth of 40 miles--all the way down to the molten core on which the continents float.

As it turns out, the violent collision also created a natural laboratory for modern-day scientists to re-examine long-held theories about the origin of oil and gas.

Today, the gaping wound created by the meteor is healed. A lush forest now covers the area, known as the Siljan Rings because of the crystalline lakes at the crater’s rim. There is now scarcely a hint of the violent event of long ago.

The drama is now indoors, in the form of a wide-ranging debate that is at times scientific, at other times philosophical and political. It revolves around a plan by the Swedish government to drill a deep natural gas well in the Siljan Rings area, about 150 miles north of Stockholm. The Swedes hope to find commercial quantities of gas there, even though conventional petroleum-industry wisdom says they should find no more than a trace.

If they find it, many long-held beliefs about the origin of oil and gas will be called into question. It would mean that there is virtually an unlimited supply of fuel deep within the Earth to light our cities and run our factories.

Most Experts Doubtful

Only a few experts outside of Sweden believe that there is any chance the Siljan Rings will yield much gas, considering the overwhelming evidence that oil and natural gas are byproducts of the decay of organic substances--primarily plants and primitive organisms trapped in basins of sedimentary rock.

Though few in number, the maverick experts have been vocal, and they found a very willing listener in the government of Sweden, a country with no known oil or gas reserves. At first the government had planned to put up nearly all of the $25 million the project is expected to cost. But as criticism of the unorthodox project mounted, some political leaders grew concerned about the possibility of looking foolish.

Changing course, the government ordered the federal power agency, Vattenfall, to raise 65% of the money from municipalities and private corporations that need the gas. The deadline has come and gone twice, but now it seems likely that the money will be there as soon as some questions are resolved over the degree of control investors will have over the project.

“We are optimistic that we will be able to do it,” said Rune Brorsson, project manager for Vattenfall, who had hoped to begin drilling the well to a depth of at least three miles by last October. The drilling is expected to take about a year.

Brorsson is well aware that nearly the entire petroleum industry believes the effort will fail. “We have emphasized (to potential investors) that this is a high-risk project,” he said in a recent interview at the Vattenfall headquarters near Stockholm.

The prime mover behind the project is neither a Swede nor an oilman. He is Thomas Gold, an astrophysicist at Cornell University who believes discoveries in astronomy during the past decade call into question the widely held theory that oil and gas are the product of organic decay.

Hydrocarbons Universal

Hydrocarbons--the basic components of oil and gas--have been shown by a new generation of astronomical instruments to be abundant throughout the universe. If the moon and comets and planets that have never known life are rich in hydrocarbons, Gold reasons, why should we think they occur in huge reservoirs on this planet only as the result of organic decay?

For more than a decade now, Gold has been attacking petroleum experts who refuse to accept his ideas. “It would mean they would have to turn their backs on their life’s work,” he says.

Gold believes that oil and gas reservoirs are formed not through organic decay, but by the slow migration of hydrocarbons to the surface from deep within the Earth.

“There is nobody in the business who, from the scientific point of view, takes his theory seriously,” said Martin Schoell, a geochemist with the Chevron Oil Field Research Co. in La Habra. “The only people he is attractive to are people who are not in the business, because it is an extremely attractive hypothesis.”

But Gold has done his homework well, winning the support of the Gas Research Institute, a trade group for the U.S. natural gas industry. The institute is funding part of the research in Sweden, subject to reimbursement if commercial quantities of gas are found. And evidence is turning up that at least partly supports his theories.

Even Gold’s critics admit that he is not easily dismissed.

“It’s so easy to lose against him,” said Schoell, who once debated Gold in a symposium in London. “If you come up with evidence, he jumps off to another subject. You cannot tie him down.”

Rise to the Surface

Gold argues that methane (natural gas) and other hydrocarbons were trapped in the Earth’s molten core 4 1/2 billion years ago. Some hydrocarbons make their way to the surface through fissures in the crust, forming reservoirs of oil and gas and coal when they reach an impermeable layer of rock near the surface, he says.

As evidence, Gold points to methane and other gases vented into the atmosphere by volcanoes.

The experts yield only slightly on that point. “Nobody would refute that some gas comes from deep Earth, but you have to evaluate it volumetrically,” said Brian Horshfield, a geochemist with the Arco research center in Houston.

Geochemists argue that while the Earth undoubtedly vented methane early in its history, it does so today only in traces.

“We’re of the opinion that the degassing occurred early in its history,” said Kenneth E. Peters, a Chevron geochemist. “The amount being added to the system now is minuscule.”

Convinced that the experts are wrong, Gold set out to find a natural “laboratory” to prove his ideas. He found it in the Siljan Rings.

The crater left by the impact from the meteor, 28 miles in diameter, is in granite, something geologists call basement rock. The area is quite different from the sedimentary basins that comprise the world’s great petroleum fields. Gold reasons that if gas is found in the Siljan Rings area, it could only have come from deep within the Earth and migrated upward from the core via fractures created by the meteor’s impact.

Studies Back Project

Swedish officials found Gold’s arguments compelling. A series of studies was commissioned, and most turned up results supporting the project. Seismic surveys indicated that the crust had indeed been fractured all the way down to the mantle--a depth of about 40 miles. The surveys also showed underground formations very similar to oil-bearing strata in known reservoirs.

Many skeptics, convinced that significant quantities of methane will not be found, are rooting for Sweden to complete the well. Some have snidely branded the project “Fools Gold.”

“All the hard evidence points against it,” said geochemist Alan Jeffrey of Global Geochemistry Corp. of Canoga Park.

That includes mountains of evidence collected over the years not to refute Gold but to help the oil industry go about its business of finding petroleum. Geologists have no reason to doubt the organic origin of oil and gas because the trail left by organic decay has led them to hydrocarbon reservoirs all over the world.

“You find it (oil and gas) where you expect to find it,” said Chevron’s Peters.

Scientists, moreover, can duplicate in the laboratory the processes believed to have occured in nature. Source rocks, for example, can be pressurized and heated to the right temperatures to create oil and gas. This process is used often by geologists to help determine if rocks are likely to yield commercial quantities of oil and gas.

A similar process can be observed in the field. Organic waste buried in dumps, for instance, decays into methane. Damp, heavily vegetated areas give off “swamp gas.”

“We understand it in the lab and we can see it in the swamps,” said Chevron’s Schoell.

Biological Signature

Equally convincing to geochemists is that oil and gas carry a specific “biological signature.” When oil is examined under a microscope, geochemists can identify the specific organisms from which it came.

“We can even determine the development of trees found in coal,” Schoell said. “And we find highly complex molecular structures which are so specific to living organisms that they cannot be formed by abiogenic (non-organic) synthesis.”

Gold, however, has an answer.

Of course chemists find evidence of organic matter when they analyze oil, he says, because plants and other organisms became trapped by the fluid as it migrated through the ground, much the way a river captures pine needles from along its banks.

Geochemists say the numbers do not match. Organic substances in hydrocarbons are too abundant and too universal to have simply been trapped.

But Gold, meanwhile, has picked up some support for his theory from research now under way in the Sacramento basin, the huge natural gas field in California’s Central Valley. Global Geochemistry of Canoga Park, working under a contract with the Gas Research Institute, has developed evidence that some of the gas now being extracted from the basin came from deep within the Earth.

In a recent report to the institute, the firm concluded that analysis of many source rocks in the basin revealed that they were too “immature” to have produced much gas. Furthermore, the gas contains a relatively high percentage of a kind of helium that occurs only deep within the Earth.

A Carrier Gas

“Recent measurements of (deep-Earth helium) indicate that deep-Earth gas has, in fact, made its way into the Sacramento basin gas fields,” the report stated, adding that the helium could have been transported through the Earth’s crust only by a “carrier gas”--carbon dioxide, nitrogen or methane.

The report concluded that the presence of so much helium indicates “a significant amount of deep-Earth methane may be present in the Sacramento basin.”

The author of the report, Peter Jenden, believes that as much as 35% of the gas in the basin may be of deep-Earth origin, but that has not led him to embrace Gold’s hypothesis.

“We have to exercise considerable caution in jumping to the conclusion that a significant amount of the methane is of deep-Earth origin,” Jenden said, “but the possibility can’t be ruled out.”

A methane molecule consists of an atom of carbon joined with four hydrogen atoms. But like helium, methane that originates deep within the Earth is chemically different from that found in gas reservoirs close to the surface.

The most easily detected difference is that a relatively high ratio of the deep-Earth methane molecules contain a rare type of carbon atom called carbon-13, which has one more neutron in its nucleus than a carbon-12 atom.

Gold claims that the heavier carbon-13 is simply stripped from the hydrogen, possibly through oxidation, as the gas migrates toward the surface. Oil-industry chemists argue, however, that oxidation is more likely to affect methane molecules with carbon-12 atoms, because the carbon-13’s bond with the hydrogen atoms is stronger.

So the debate rumbles on, with geochemists and petroleum geologists agreeing almost universally that Gold is wrong.

Still, many of them concede, the hypothesis is intriguing.

“If they find substantial quantities of methane in that well,” one chemist said after spending two hours debunking Gold’s theory, “it will be very hard to explain.”