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Vol. 231 No. 12 |
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HENRY TERRELL, CONTRIBUTING NEWS EDITOR
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Everything you know is wrong, unless it isn’t
An item came across the news wires last spring. It caught my attention because the source was straightforward, standard oil industry news, but the subject was unusual: “Mantle convection impossible, says prominent geoscientist” (or something like that). First thought: Huh? Second thought: There’s got to be more to it than this. Digging to the bottom of the news item, the real story emerged. The original source was a paper in an Indian scientific journal, and the author, a scientist who has dwelt and argued on the fringes for decades, “disproves” mantle convection in one page, discards subduction on the next, and then dismisses plate tectonics entirely. I kept going further, looking for the gist, and this was it: “… research indicates that the earth may be creating oil from mantle methane and perhaps abiotic hydrocarbons … We should be energy independent.”
So what caused the rift-and-range features we see on the Earth today? The planet is expanding, says the scientist. It is now nearly twice the size it was during the age of the dinosaurs. That was a head-turner. What has that got to do with oil and gas? We’ll get to that.
Arcane versus popular. Most scientific debates take place outside the view of regular folks. The ideas are complicated and the terms obscure. So it was for decades with “abiogenic” or “abiotic” petroleum theory (I’ll go with “abiotic” because it’s easier to type.) These ideas date back to the 19th century theories of Alexander von Humboldt and Joseph Louis Gay-Lussac. In the early 1950s, Nikolai Alexandrovich Kudryavtsev developed what became known as the Russian–Ukrainian theory of abiotic petroleum and natural gas. Simply put, the theory suggests that petroleum deposits did not form principally from organic marine sediments. Instead, they have been buried deep in the earth since the planet formed, but have migrated up from these deep strata as methane and were transformed by heat and pressure into more complex hydrocarbons.
The Austrian-born astronomer Thomas Gold popularized these theories in the West, and much of the modern excitement dates from the publication of his book The Deep Hot Biosphere: The Myth of Fossil Fuels. This book, aimed at a general audience, began to push the subject into the mainstream, spawning articles in popular magazines and newspapers.
The existence of abiotic methane is not in dispute. Carbon and hydrogen are among the most abundant atoms in the universe, and methane is the simplest combination of these. Methane has been discovered in meteorites, and may exist in vast quantities on other planets. The Saturnian moon Titan supposedly has lakes of liquid methane. The more important question is whether these simple hydrocarbons are transformed into the long-chain variety, accounting for the “fossil” fuels we produce today. Gold and those who followed him argued that petroleum is formed from the reaction of carbonates with iron oxide and water deep within the Earth’s mantle. Further, organisms found at extreme depths interact with this abiotic petroleum, providing biological “markers” and falsely indicating that oil has a biological origin.
Weak versus strong. It’s important to point out that abiotic oil theory exists in two main versions. The first, the “weak” theory, says that abiotic petroleum exists, but is produced too slowly to replenish the Earth’s reserves. This theory has consequences for exploration—that is, where should we look for oil? Politically, though, it is innocuous.
The second, “strong” theory says that not only does abiotic petroleum exist but it is being produced at a fantastic rate that will allow reserves to effectively last forever, replenishing themselves. The theory has political and social consequences, and this is where it gets sticky. A series of popular, much shriller writers has dived into the scrum, the relative dignity of academic debate getting lost in the noise. (These appeared as a direct challenge to “peak oil” theory, which has had its share of glassy-eyed proponents.)
For example, a review of a recent popular book concludes: “Oil was formed from dead dinosaurs and we are running out of it—or so the big oil companies would have us believe.” Aside from the fact that nobody seriously believes petroleum came from dead dinosaurs (ancient marine organisms perhaps, but not dinosaurs), anytime an argument devolves into belief that your opponents are conspirators with a hidden agenda, reason has gone out the window. We go from “There is not yet an unambiguous way to ascertain the extent to which petroleum might be of abiotic origin” to “Fraudulent science and irresponsible politics have been sold to the American people in order to enslave them.” Whoa. It becomes difficult to suggest that conventional models of fossil fuels are correct—without being dismissed as a tool of government or big business.
Puffed up. Expanding Earth theory is usually associated with belief in limitless petroleum, as basement rock cracks and hydrocarbons well up, filling depleted reservoirs. In this model, the world had a solid layer of crust 200 million years ago, then began expanding rapidly, resulting in the shapes of the land masses we see today. Subduction of oceanic crust, evidence aside, cannot exist. (“Subduction denialism” it’s called. Really.) Suggested mechanisms for this vary wildly, from the plausible to the nearly magical.
It’s one thing to subscribe to unorthodox theories, and another to persuade governments to change policies or investors to pony up. Ask the government of Sweden and the private investors who, at the behest of Thomas Gold, paid for two wells to be drilled in the Siljan Ring, a 368 million-year-old meteor crater. Gold predicted that deep fracturing of the crust should have allowed significant hydrocarbons to migrate upward and accumulate. Three years and $40 million later, the wells could go no deeper, and only trace hydrocarbons had been found.
Petroleum reserves have increased in recent years, but this is due to better science, better technology and improved models, not methane bubbling up from the depths. Petroleum geology is a science that has evolved through a process of theory and testing. Accurate models produce oil, and inaccurate ones make dry holes.
Petroleum geologist Colin J. Campbell may have put it best: “Oil is ultimately controlled by events in the geological past which are immune to politics.”
Or so the big oil companies would have us believe. 
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