A rebuttal of Thomas Gold’s theory of abiotic hydrocarbons

 
To: Rich Kolm

You say you:
 "... don't believe oil and gas come from plants but rather are the products of methane outgassing that has been going on since the planet formed, long before plants existed or photosynthesis began... The best presentation of the evidence from a scientific viewpoint is in the Thomas Gold book ...  The best practical evidence is the success of the Russian/Ukrainian oil exploration program based on this viewpoint. "

That is very much an "outlier" view.

I've never before come across anyone who has held that view.

There are a few difficulties with someone using either the work of Gold, or of Russian researchers such as  Professor Vladimir B. Porfir'ev, senior petroleum exploration geologist for the former U.S.S.R., to try to argue against taking action on AGW (Anthropogenic Global Warming):

1) Gold's work on abiotic hydrocarbons, and the consequent suggestions for preponderance of abiotic sources of carbon based greenhouse gases in the atmosphere in recent times (200 years), have been rebutted (see more below)

2) Gold, and the researchers he cites, do not deny the greenhouse effect

3) Gold suggests unsubstantiated and unidentified natural 'compensating drawdowns' of carbon from the atmosphere (similar to some form of Lovelock's Gaia Theory - more about this below, in comments about Gold using Lovelock as one of his referenced sources) - such compensating drawdowns are not supported by credible scientific evidence.  In contrast, the scientific evidence shows how human activities, primarily the burning of fossil fuels, have put the carbon cycles significantly out of balance in the last 200 years, and geological processes will take much longer than 200 years to do any significant 'compensating' in response.  Such processes might eventually direct the system towards a new equilibrium, but that equilibrium is only possible in geological timescales (perhaps many thousands of years, or millennia), not meaningful human societal ones.

4) The 'Russian/Ukrainian example', in support of Gold's theory, has been shown to fail to support his theory in the way claimed by some (see more on this from Glasby below).


One interesting observation by the Washington Post:
https://www.washingtonpost.com/archive/opinions/2001/05/20/a-look-at-mad-science/493803c9-2ccc-494c-bdac-431b40562450/

"... there's also a bad news side of the story if Gold is right. If the world does have centuries more of "fossil" fuels than most geologists believe, the danger of global warming is potentially much greater over the long term [than previously thought]"

I will do a bit more of a dive into this topic here, because although Gold's theory is an outlier and has been rebutted in its main assertion and suggested implications, that doesn't mean it has nothing at all to offer.

Here goes ...

Gold (1982) is rebutted by Glasby (2008) “Abiogenic Origin of Hydrocarbons: An Historical Overview”, from which:

“Thomas Gold's theory involves degassing of methane from the mantle and the formation of higher hydrocarbons from methane in the upper layers of the Earth's crust. However, formation of higher hydrocarbons in the upper layers of the Earth's crust occurs only as a result of Fischer-Tropsch-type reactions in the presence of hydrogen gas but is otherwise not possible on thermodynamic grounds. This theory is therefore invalid, [and has] been overtaken by the increasingly sophisticated understanding of the modes of formation of hydrocarbon deposits in nature… there is a fundamental flaw in Thomas Gold's theory of abiogenic petroleum formation. As previously pointed out, methane can only be converted to higher hydrocarbons at pressures >30 kbar corresponding to a depth of ~100 km below the Earth's surface. The proposed reaction of methane to produce higher hydrocarbons above this depth and, in particular, in the upper layers of the Earth's crust is therefore not consistent with the second law of thermodynamics. Furthermore, bacteria cannot catalyze thermodynamically unfavourable reactions. Gold's deep gas theory in which hydrocarbons are supposedly formed from methane in the upper layers of the Earth's crust is therefore invalid.   ”
 
See also what Glasby says about Russian hydrocarbon exploration success, which some claim was due to Russian / Ukrainian theories about deep sources of abiotic hydrocarbons:

“… this explanation is contrary to the facts. The great oil fields of the Volga-Urals region, the northern Urals and western Siberia were discovered during and after the Great Patriotic War (early 1940s to middle 1950s). These fields were found not as a result of the theories of the N. A. Kudryavtsev and V. P. Porfir'ev which were too abstract and geologically too vague to be of practical use but as a result of clear empirical relationships which gave "the final word to the borehole". On this basis, the Soviet theory of deep, abiotic petroleum origins was never the driving force in the discovery of the major oil fields in the Soviet Union as its proponents claim.”
 
Glasby concluded:
 
“…  at the time that the abiogenic theory was at its peak from the 1950s to the 1980s, it was not possible to assess the relative merits of [the] two theories objectively on the basis of the then existing scientific data and this only became possible with the development of much more sophisticated techniques for the analysis of the organic constituents in petroleum such as GC/MS in the 1980s. As a result, a much more detailed understanding of the pathways of organic constituents from source rocks to petroleum was established which offered convincing evidence to support the biogenic theory. By contrast, the abiogenic theory made no real attempt to explain the formation of the very complex mixture of organic compounds which make up oil… The deep gas theory of Thomas Gold is based on the assumption that deep faults play the dominant role in the continuous migration of methane and other gases to the Earth's surface and that this methane is then converted into oil and gas in the upper layers of the Earth's crust. However, this reaction is not thermodynamically favourable under these conditions and can not be facilitated by the presence of bacteria. In addition, deep drilling of the Siljan Ring did not offer any convincing evidence for a dominant mantle source for hydrocarbon formation there. This theory is therefore invalid.”
 
 
Gold’s most detailed theory is said to be included in:
Gold (1987) “Power from the Earth: Deep Earth Gas — Energy for the Future”
I haven't reviewed that book. 

I have, however, obtained Gold (1999) "The Deep Hot Biosphere - The Myth of Fossil Fuels".  Note that Gold does not deny the greenhouse effect.  This is what Gold (1999, p194)  says about it:
 
“… because the sun is slowly heating up, a runaway greenhouse is in the earth's future, too-but not for billions of years. A runaway greenhouse works in this way: First, higher radiation intensity means a hotter climate to begin with, which vaporizes more liquid water on a planet's surface. The hotter climate also permits more of that water vapor to linger in the atmosphere before falling out as rain. Water vapor is a greenhouse gas-in fact, it is the most effective greenhouse gas in the earth's atmosphere…  and enabling the atmosphere to hold even more water in a vapor state-which feeds back on the amount of heat retained by the earth, and so on... Any carbon is likely to be oxidized to carbon dioxide, which is fated to remain in the atmosphere ... CO2 is a potent greenhouse gas.. So long as the planet continues to drive out carbonbearing gases from its interior, CO2 will accumulate in the atmosphere.”

He seems to suggest, however, that some forms of what might be called ‘compensating drawdowns’ of carbon occur, which prevent a buildup of carbon-based greenhouse gases occurring over timescales shorter than billions of years.

Two scientific references he cites regarding runaway global warming are:
“The time for onset of a runaway greenhouse on the earth has been estimated by James Lovelock and Michael Whitfield in their 1982 "Life span of the biosphere," Nature 296: 561-63. A more recent estimate is given in Ken Caldeira and James F. Kasting, 1992, "The lifespan of the biosphere revisited," Nature 360: 721-23.”
 
The abstract from Lovelock (1982) is as follows:

“Abstract
There has been life on Earth for at least 3,500 Myr but the assumption that a comparable future lies ahead may not be justified. Main sequence stars appear to increase their burning rate as they age. Thus the Sun, if a typical star, can be predicted to have increased its output by 30% since the Earth's origin 4,500 Myr ago. The maintainance of an equable climate since life began probably required some means of planetary thermo-stasis. The Gaia hypothesis proposed by Lovelock and Margulis included an unspecified biological means for climate control. Walker et al. suggests an abiological automatic thermostasis in which the atmospheric abundance of CO2, a greenhouse gas, adjusts to resist the warming tendency of the increased solar flux. Here we discuss possible links between the biological and geological control mechanisms. It is clear that whatever the mechanism, atmospheric CO2 is now close to its lower limit of partial pressure, so the biosphere may soon, in geological terms, be exposed without protection to the predicted progressive increase of solar luminosity.”
 
Excerpts from Caldeira (1992):
 
“… reductions in atmospheric CO2 concentration could maintain a constant temperature for the next 0.9 Gyr…If future ocean waters are roughly in chemical equilibrium with silicates and carbonates, ocean pH would be buffered close to its present value … our model does not include the possible negative feedback of increasing cloud cover… “
 
 
Gold (1999) chapter 4 seems to present his best evidence:

“Invasion of an area by hydrocarbon fluids from below could better account for the vertical reach of hydrocarbons than does the chance of successive deposition of hydrocarbon-producing biological sediments in epochs that differ by tens of millions of years and that show no similarities of climate, vegetation, or other relevant characteristics...methane is found in many locations where a biogenic explanation for its presence is improbable or where biological deposits seem inadequate to account for the size and extent of the methane resource”
 
And he also suggests:

“The view that the main carbon supply to the surface comes from volcanic emission of carbon dioxide is thus in doubt, so long as no estimate has been made of the sum of the diffuse outflows of methane over all sea and land surfaces.”
 
Gold (1999), page 66, seems to describe the gist of his view on non-biological origins of hydrocarbons:
 
“Upwelling methane would be subject to fractionation wherever it passes through a wet spot in the rocks or a particularly tight network of pores. Indeed, very large factors of fractionation can be obtained by multiple stacked diffusion systems, which may easily be encountered during the upward journey of hydrocarbons originating at great depth. Such an extended process of fractionation would account for the extreme values of C-13 deficiencies recorded for hydrocarbons sampled in some locations-greater values than have been reported in plants anywhere. Nevertheless, the interpretation that only biology could produce significant fractionation has been adopted so overwhelmingly that whenever the light carbon isotope is found to be favored in a subsurface solid or fluid, life is unquestioningly held responsible.”
 
Supposedly in support of this, he references the following, in the notes to chapter 4, but the cited reference contradicts what Gold says in the body of his text.  An excerpt from the reference note:
“P.J. McCabe, D.L. Gautier, M.D. Lewan, and C. Turner (members of the U.S. Geological Survey) in "The future of energy gases," USGS Circular 1115,1993. They conclude: "So far no economic accumulations of gas have been found that cannot be explained by the organic theory. Geochemical analysis from producing fields in the United States, for example, clearly shows that over 99 percent of the gas is of organic origin".”
The cited reference above contradicts what Gold says.
 
Gold proceeds:

“the abiogenic theory would also offer a satisfactory explanation. Methane molecules bearing the heavier isotope of carbon would ascend more slowly through the rock than would molecules bearing the lighter isotope. Diffusion from pore to pore would be slowed. The longer transit time would subject those heavier molecules to more opportunities for oxidation. The carbon component of many of those heavy methane molecules would thus oxidize into carbon dioxide, which would continue the ascent. Carbon dioxide emanating from the earth is, in fact, enriched in the heavy isotope compared with hydrocarbons. To test this explanation, however, would require far more accurate data-not only on the isotopic differences between methane and carbon dioxide outgassing but also on the relative quantities of each released into the atmosphere…  I maintain that only the abiogenic theory can satisfactorily account for the carbon isotope composition of the carbonates that constitute the major component of the earth's inventory of surface carbon  ” [he provides no references here to support his theory]
 
“On the basis of the abiogenic theory we would consider most of the unoxidized carbon deposits in the crust as derived from upwelling hydrocarbons, not from any sediments coming from the atmosphere” [he provides no references here to support his theory]
 
“there are hundreds of examples drawn from core samples of oil wells, from carbonate deposits on the ocean floor that overlie gas production areas, and of course from our wells in Sweden. Would they all have acquired gases in comparable amounts from two different sources, one of them being biogenic? Would there not be many locations where only one source and not another had contributed? How would biogenic methane have made its way down 500 meters (or indeed, six kilometers) into the granite of Sweden, starting from a surface that had a sedimentary cover barely sufficient to hide the bedrock?” [he provides no references here to support his assertions]
 
He concludes the section as follows, having provided no additional references to any scientific or technical work supporting his theory:

“In sum, the technical information and arguments in this section lead, in my view, to a straightforward general conclusion: The volumes, ages, and isotope ratios of crustal carbonates represent important evidence in favor of the view that hydrocarbons were primordial constituents of the earth, that they remain still, and that they continuously upwell into the outer crust, finally emerging, oxidizing, and mixing in the atmosphere.”
 
 
Gold goes on to say:

“On our own water-rich world, the carbon atoms have been removed from the atmosphere at about the same rate at which they were supplied by outgassing from the depths of the earth. Methane and carbon dioxide are the principal sources of carbon entering today's atmosphere, as noted in earlier chapters, and methane also turns quickly into carbon dioxide and water in our oxidizing atmosphere. The statistics of boreholes and the investigation of meteoritic materials (the leftovers of the construction of the planets) both strongly suggest that methane is the major gas involved. Carbon dioxide is withdrawn again from the atmosphere, permanently or on a long-term basis, mainly by being sequestered in carbonate rocks deposited on the ocean bottom [no references provided to support this assertion].  Interestingly enough, had this water-mediated route for carbon dioxide removal not been functioning on the earth, our own atmosphere would now hold just about as much carbon dioxide as does that of our sister planet Venus, where the surface atmospheric pressure is about eighty times ours. There would be no oceans, no rain, and no surface biosphere… ”
 
It appears that both Lovelock (1982) and Caldeira (1992) recognise and model the greenhouse effect, but they do it on long-term timescales of Gigayears (a thousand thousand thousand years).  They ignore human-driven greenhouse gas emissions from human activities (principally the burning of fossil fuels) in the last couple of hundred years.  Lovelock appears to be assuming, perhaps along the lines of his Gaia Theory, a compensating drawing down of carbon from the atmosphere to counteract the carbon emissions from sources on the ground or ocean (including those from human sources such as burning of fossil fuels). 
 
It seems that two theories of abundance of abiotic (non-biological sourced) hydrocarbons in the Earth's carbon cycle, which gained popularity in some quarters, including among some Russian scientists, in the 1950s, has been found to be invalid and/or unsubstantiated by more modern scientific methods and data sources than were available at that time.    

A small proportion of people still hold on to such theories of abiotic hydrocarbons as an alternative explanation of concentrations of carbon-based greenhouse gases in the atmosphere (through natural "degassing" instead of from human-generated sources such as burning of fossil fuels).  Such arguments seem to rely more on some form of Gaia theory (as proposed by Jonathan Lovelock, one of the people cited by Gold), involving some largely unspecified mechanism whereby carbon released into the atmosphere (whether from natural or human-made sources) is somehow compensated for by equal amounts of drawdown of carbon from the atmosphere. 

It's true that there are large scale geological and chemical mechanisms in the carbon cycle that, over very long timescales of millions, or even billions, of years, tend to create an equilibrium state for the planet and biosphere.  However, Gold's theory (and earlier similar ones) have been invalidated by more recent advances in scientific methods and data.  Furthermore, what is missing from discussions relying on such a frame and narrative as Gold's is the impact humans have had, over a geologically short timescale (of a couple of hundred years).  Since the Industrial Revolution, we have intervened in the carbon cycle, and dramatically increased the rate of addition of carbon based greenhouse gases into the atmosphere, causing dangerous climate change.   Gold does not address that topic, although a small number of people citing his work have tried to suggest that, because of abiotic sourcing of hydrocarbons, human-driven emissions of carbon based greenhouse gases cannot be the cause of recent global warming and climate change.  Their suggestions can be rebutted by modern work that outlines the "human fingerprint" on greenhouse gases in the atmosphere.  Gold does not offer any counterevidence to this.

So, while Gold's theory about abiotic hydrocarbons is interesting, it is scientifically rebutted.  And, even if his theory was right, it would not rebut the human fingerprint on recent high rates of greenhouse gas emissions and consequent global warming and climate change.  There is a logical mis-step by people arguing against AGW using such an inference.
 
I think at the root of this debate is that misinterpretations, misunderstandings, mis-steps in logic and misplaced beliefs can arise from:

a) trying, unsuccessfully, to reconcile the processes occurring over geological timescales with those that are occurring (and being affected by humans) in timescales covering only decades or centuries

b) assuming (without sufficient evidence) some form of Gaia-like compensating natural mechanism to 'correct' for human-driven emissions of greenhouse gases over timescales of decades or centuries

c) ignoring, or otherwise failing to refute, the scientific evidence for the "human fingerprint" on greenhouse gas emissions from human activities

d) assuming essentially all greenhouse gas emissions are from natural processes (eg abiotic hydrocarbons)  or that greenhouse gas emissions from human activities are negligible, without providing compelling evidence to support either assumption