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But were Armitage's words un...,
peak oil theory:
Chomsky's declaration that "The basic theory is incontrovertible" reminded me of some rantings on abiogenic petroleum origins from the recently-deceased physicist Thomas Gold, possibly plagarized to some extent from Russian-Ukranian geologists. Most of the online debate is haberdash, since everybody's got an agenda.
The energy czar from From the Wilderness only makes one concrete argument against abiogenic theory:
the chemistry of magma does not compare to the chemistry of hydrocarbons. Magma is lacking in carbon compounds, and hydrocarbons are lacking in silicates. If hydrocarbons were generated from magma, then you would expect to see some closer kinship in their chemistry.
I'm just a layman and so risk making an ass out of myself - just like I do on everything else - but this argument has no bearing on the abiogenic theory I've read about: that simple hydrocarbons were trapped in the earth during the earth's formation and are being driven upwards by subduction of heavier materials, under such conditions and in the presence of extremophile bacteria that the basic hydrocarbons interact, producing oil, etc. - hydrocarbons wouldn't be chemically "generated from magma".
Furthermore, because the theory isn't being used in oil exploration then present oil production peaks and price spikes (almost entirley the result of politics and rising demand: e.g. Russia's shutting down their largest oil company, war in Iraq, recovering economy, China developing, ad infinitum) wouldn't really have any bearing on the theory since its precepts are not being tested in the oil production chain.
The FTW guy is also arguing that world oil production peaked in 2000, and so the crisis era is pending. Indeed production peaked. Since 1980 [see: IEA 2002, table 2.2, "World Crude Oil Production (Thousand Barrels per Day), 1980-2002"] world oil production also peaked in 1980, 1984, 1990, and 1998, so to argue that 2000 was the Hubbert peak (the crisis point beyond which we run out of oil) you end up needing estimates of world oil recoverable reserves and vaguer estimates of oil "to-be-found", which are estimates based off assumptions derived from biogenic theory just as the disovery methods are based from biogenic theory, and one wonders about the accounting methods. If abiogenic theory is right all this is all wet, because disovery methods are based off faulty assumptions and would explain falling discovery rates and give rise to the oil crisis predictions. If the abiogenic hypothesis is correct you'd still have a peak production rate and increasing recovery costs, you'd still have global warming and other petrol-related environmental concerns, and so you still have good reason to develop greener fuels, there's just no pending oil crisis of epic proportions to shutdown the world economy, which is disputable either way anyway.
There's a lot of silly reading along this line, like whether abiogenic oil was discovered in the Swedish drilling project Gold took part in (drilling into a prehistoric meteor crater, being non-sedementary rock): critics call what he found there 'economically unviable' amounts of oil, proponents call it 'non-negligible', both of which, I suppose, are perfectly accurate descriptions of what was found (~80 barrels, I read somewhere), neither says anything about whether it supports abiogenic theories. As Roger Sassen is quoted in this skeptical inquirer article, "no one who is objective discusses the issue at this time".
Along the line of similar discoveries in non-sedimentary source rock - which would prop up abiogenic theory - proponents point to the Dnieper-Donets Basin in the Ukraine (e.g. JF Kenney and his Gas Resources Corporation out of Texas) where major oil deposits are found in the basement, indigenous rock, rather than sedimentary material where fossil material would be found. This supposedly proves that the oil derived from abiogenic hydrocarbons. But this doesn't, by itself, prove anything, since oil discoveries in fractured basement reservoirs is relatively common - if generally left unexplored and found by accident - and the oil found could derive from overlying or trapped sedimentary material just as it could from bacteria deep in the crust. Observed re-filling of some resevoirs might be explained by the same.
Dig around enough and you run across Barbara Sherwood Lollar (see her contribution to the july/august issue of Chemical News [pdf]), who looked at isotope fractionation (specifically C12 to C13 isotope distributions in the alkane series of hydrocarbons - meaning stuff that has a chemical formula like CnH2n+2, methane being the most common) among gasses taken from Kidd Creek Mine in precambrian, indigenous rock. Larger alkanes tend to have far less C13 than smaller ones because the lighter carbon atoms react more readily to form the larger molecules. It happens that this distribution is distinctive between biogenic and abiogenic pathways to producing the larger alkane molecules, and so one can distinguish between them. The hydrocarbons she took from the mine matched abiogenic distributions, a demonstration that abiogenic hydrocarbons do, in fact, form inside the earth.
The problem here is when biogenic proponents then take this theory and argue that because commercial oil deposits contain hydrocarbons that match the isotope distributions for biogenic generation this disproves abiogenic genesis of commercial oil: what Sherwood actually demonstrates is that there are abiogenic hydrocarbons in the earth that may exist in sufficient quantities to support bacterial life deep inside the earth - e.g. Gold's "deep biosphere". If these bacteria sufficiently interact with mantle hydrocarbons the isotope distribution would presumably be altered to match biogenic patterns: once again niether side scores.
One last related topic I found while zooming around the net today, where it gets thrown about as evidence for the abiogenic hypothesis - which it could be but nobody knows yet, looks like this:
Vast quantities of methan hydrate ice have been found in the ocean, feasibly offering an indefinite supply of carbon based energy, e.g.: "Natural gas hydrates represent an enormous hydrocarbon resource that could potentially satisfy the energy needs of the world for centuries. The primary known repositories of methane hydrates are arctic permafrost zones and undersea basins on the continental margins. Major R&D programs to investigate methane hydrates have been initiated in Japan, India, and recently in the U.S.".
The American Geological Institute has more on how the politics of - they say 200,000 trillion cubic feet of - frozen natural gas plays out in congress.
All this brings me to a DeLongesque "oh why can't we have better scientific journalism", but whatever, he's already covered that. Time to go to the bar.
:: posted by buermann @ 2004-07-29 19:41:04 CST |