The 'Abiotic Oil' Controversy

By Richard Heinberg
The debate over oil's origin has been going on since the 19th century. From the start, there were those who contended that oil is primordial - that it dates back to Earth's origin - or that it is made through an inorganic process, while others argued that it was produced from the decay of living organisms (primarily oceanic plankton) that proliferated millions of years ago during relatively brief periods of global warming and were buried under ocean sediment in fortuitous circumstances.
During the latter half of the 20th century, with advances in geophysics and geochemistry, the vast majority of scientists lined up on the side of the biotic theory. A small group of mostly Russian scientists - but including a tiny handful Western scientists, among them the late Cornell University physicist Thomas Gold - have held out for an abiotic (also called abiogenic or inorganic) theory. While some of the Russians appear to regard Gold as a plagiarist of their ideas, the latter's book The Deep Hot Biosphere (1998) stirred considerable controversy among the public on the questions of where oil comes from and how much of it there is. Gold argued that hydrocarbons existed at the time of the solar system's formation, and are known to be abundant on other planets (Jupiter, Saturn, Uranus, and some of their moons) where no life is presumed to have flourished in the past.
Thus even if the abiotic theory does eventually prove to be partially or wholly scientifically valid (and that is a rather big "if"), it might have little or no practical consequence in terms of oil depletion and the imminent global oil production peak.
Oil at the Core?
Gold is right: there are hydrocarbons on other planets, even in deep space. Why shouldn't we expect to find primordial hydrocarbons on Earth?
Refilling Fields?
A significant reservoir of crude oil was discovered nearby in the late '60s, and by 1970, a platform named Eugene 330 was busily producing about 15,000 barrels a day of high-quality crude oil. By the late '80s, the platform's production had slipped to less than 4,000 barrels per day, and was considered pumped out. Done. Suddenly, in 1990, production soared back to 15,000 barrels a day, and the reserves which had been estimated at 60 million barrels in the '70s, were recalculated at 400 million barrels. Interestingly, the measured geological age of the new oil was quantifiably different than the oil pumped in the '70s. Analysis of seismic recordings revealed the presence of a "deep fault" at the base of the Eugene Island reservoir which was gushing up a river of oil from some deeper and previously unknown source. (8)
A "river of oil" from an unassociated deep source? This does sound promising. But closer examination yields more prosaic descriptions and explanations.
While it is true that the estimated oil reserves of Eugene have increased, the numbers are not extraordinary. The authors note that "From 1978 to 1988, these operations, activities, and natural factors [including better exploration and recovery technology] have increased ultimate recoverable reserves from 225 million bbl to 307 million bbl of hydrocarbon liquids and from 950 bcf to 1.65 tcf of gas." Other estimates now put the estimate of total recoverable oil as high as 400 Mb.
None of this is especially unusual for a North American oil field: most fields report reserve growth over time as a consequence of Securities and Exchange Commission reporting rules that require reserves to be booked yearly according to what portion of the resource is actually able to be extracted with current equipment in place. As more wells are drilled into the same reservoir, the reserves "grow." Then, as they are pumped out, reserves decline and production rates dwindle. No magic there.
The evidence at Eugene Island suggests the existence of deep source rocks from which the reservoir is indeed very slowly refilling - but geologists working there do not hypothesize a primordial origin for the oil. In "Oil and Gas - 'Renewable Resources'?" Kathy Blanchard of PNL writes, "Recent geochemical research at Woods Hole Oceanographic Institution has demonstrated that the wide range in composition of the oils in different reservoirs of the Eugene Island 330 field can be related to one another and to a deeper source rock of Jurassic-Early Cretaceous age." (10) Her article explains that this kind of migration from nearby source rocks is hardly unique, and discusses it in the context of conventional biotic theory. A technical paper by David S. Holland, et al., "Eugene Island Block 330 Field - U.S.A. Offshore Louisiana," published by AAPG, notes that the Eugene Island oils show
In addition, oil typically contains biomarkers - porphyrins, isoprenoids, pristane, phytane, cholestane, terpines, and clorins - which are related to biochemicals such as chlorophyll and hemoglobin. The chemical fingerprint of oil assumed to have been formed from, for example, algae is different from that of oil formed from plankton. Thus geochemists can (and routinely do) use biomarkers to trace oil samples to specific source rocks.
Abiotic theorists hypothesize that oil picks up its chemical biomarkers through contamination from bacteria living deep in the Earth's crust (Gold's "deep, hot biosphere") or from other buried bio-remnants. However, the observed correspondences between biomarkers and source materials are not haphazard, but instead systematic and predictable on the basis of the biotic theory. For example, biomarkers in source rock can be linked with the depositional environment; that is, source rocks with biomarkers characteristic of land plants are found only in terrestrial and shallow marine sediments, while petroleum biomarkers associated with marine organisms are found only in marine sediments.
The Bottom Line
The points discussed above represent a mere sampling of the issues; it would be difficult if not impossible for me to address all of the arguments put forward by the abiotic theorists in a brief essay of this nature. I circulated a draft of this essay on two energy-related email newsgroups and received about a dozen thoughtful comments, one defending the abiotic theory but most of the others critiquing it. About half of the comments were from physicists, geophysicists, or geologists. It quickly became apparent to me that a book-length treatment of the subject is called for.
J. F. Kenney has put forward a succinct and persuasive paper arguing for the abiotic theory (5), but there is no prominently published rebuttal piece that systematically discusses or attempts to refute his assertions. A reader of Kenney's web site might find fault with some of my statements in this essay (for example, as a counter to my description of the depth "window" of oil formation, a reader might refer to Kenneyís discussion of Russian experiments that have shown that oil can be formed at high temperatures and high pressures - conditions similar to those that must exist in the Earthís mantle). Yet among the draft comments I received from scientists were convincing criticisms of Kenney's claims (returning to my example: even if oil were formed in the mantle, as more than one commenter pointed out, abiotic theorists have suggested no plausible means by which it could rise to the depths at which we find it without passing through intermediary regions in which the temperature would be too high and pressure too low for liquid hydrocarbons to survive). Many other assertions made by Kenney and critiqued by the experts are more technical in nature and more difficult to summarize.
Now, I like scientific mavericks; I tend to cheer for the underdog. Peak oil is itself a maverick idea, and for the past several years I have been promoting a view that the Wall Street Journal recently described as "crackpot." (14) So I feel a bit unaccustomed and even uncomfortable now to be on the side of the scientific "establishment" in arguing against the abiotic oil theorists. The latter certainly deserve their day in the court of scientific debate.
Perhaps one day there will be general agreement that at least some oil is indeed abiotic. Maybe there are indeed deep methane belts twenty miles below the Earthís surface. But the important question to keep in mind is: What are the practical consequences of this discussion now for the problem of global oil depletion?
I have not personally inspected the oil wells in Saudi Arabia or even those in Texas. But nearly every credible report that I have seen - whether from the industry or from an independent scientist - describes essentially the same reality: discoveries are declining, and have been since the 1960s. Spare production capacity is practically gone. And the old, super-giant oil fields that the world depends upon for the majority of its production are nearing or past their all-time production peaks. Not even the Russian fields cited by the abiotic theorists as evidence for their views are immune: in June the head of Russia's Federal Energy Agency said that production for 2005 is likely to remain flat or even drop, while other officials in that country have said that growth in Russian production cannot be sustained for more than another few years. (15)
Given the ongoing runup in global petroleum prices, the notion of peak oil hardly needs defending these days. We are seeing the phenomenon unfold before our eyes as one nation after another moves from the column of "oil exporters" to that of "oil importers" (Great Britain made the leap this year). At some point in the very near future the remaining nations in column A will simply be unable to supply all of the nations in column B.
3. http://wow.osu.edu/Geology/ebmf.htm
4. See Kenneth Deffeyes, Hubbertís Peak, pp. 21-22, 171; Walter Youngquist, Geodestinies, p. 114.
5. www.gasresources.net/energy_resources.htm
6. www.dur.ac.uk/react.res/RRG_web/hydrocarbons_meet.htm
7. www.911-strike.com/pfeiffer.htm (link expired; click on "cached")
8. www.wnd.com/news/article.asp?ARTICLE_ID=38645
11. www.datapages.com/97015/eugene.htm
12. See footnote 9.
13. www.giss.nasa.gov/gpol/abstracts/1997/FungFieldB.html
14. "As Prices Soar, Doomsayers Provoke Debate on Oil's Future," 9/21/2004
- Richard Heinberg is the author of Powerdown: Options and Actions for a Post-Carbon World and The Party's Over: Oil, War and the Fate of Industrial Societies; he is a Core Faculty member of New College of California in Santa Rosa. www.museletter.com



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