Wednesday, June 27, 2007

Vast Oil and Life in the Deep-Earth.

Two books speculate (convincingly in my opinion) on the presence of a realm of bacterial life in the Earth's crust down to a depth of about 10 kilometers, that feed on oil which is also down there in massive quantities. It is proposed that Peak Oil is a myth, based on conventional wisdom in the West that petroleum (crude oil) is the product of effectively "cooking" plant and animal remains over millennia, when really it is produced all the time by geochemical processes within the deep-earth and upwells continually, percolating through the pores present in rocks to collect in deposits closer to the surface. Natural gas too is proposed to originate in vast volumes from such inner-planetary processes, and for example the existence of methane-hydrates in large areas of sediments under the oceans and on land, under permafrost it is suggested is a consequence of "capping" the gas in and under ice-layers. I have written about this interesting material before in the posting "Methane Gas Hydrates - Vast Energy Resource or Ecological Disaster Awaiting?", posted December 4th, 2006.

The one book is "The Deep Hot Biosphere" by Thomas Gold (DHB) and the other is "Jagged Environment" by Chris James (JE). The two are quite different in character: DHB proposes very many convincing scientific arguments, supported by observations while JE expresses through its own conclusions an Earth-centred human philosophy. Where both are concurrent is in considering the origins of life. DHB takes the viewpoint of "panspermia", that the essential seeds for life came to Earth from elsewhere in the universe, perhaps in the form of fully compiled bacteria, and having arrived, life then took-hold either in the surface or deep-earth regions, in the latter case feeding off naturally produced petroleum. In contrast, JE speculates that an interaction occurs between water and silicon carbides within the earth itself, thereby producing petroleum and silica grains of the size normally found in bacteria. By coating the grains with "oil" a semipermeable membrane is formed and "life" per se originated as levels of complexity were added. One interesting notion is that the effect of background radiation was to oxidise the primitive "oil-membranes", ironically forming antioxidants which extended their lifetimes against oxidation. Thus the stress of oxygen and radiation are seen as being essential to early cellular evolution.

Both DHB and JE propose that the creation of oil and life are continual, ongoing events, which might if true appear reassuring as a notion, viewed against the backdrop of peak oil, in its suggestion that oil is not really running-out.

There is a contrast of opinion between geologists in the West and in Russia over the origins of petroleum. Essentially, the Russian/Ukranian view is that it is formed independently and deep in the earth by "abiotic" geochemical processes, in contrast to the idea of a "biotic" origin which reigns supreme in western thinking. Interestingly, the renowned British chemist, Sir Robert Robinson, was also of the opinion that petroleum could not have arisen from plant/animal material because it contained too much hydrogen as a ratio with carbon compared to these potential precursors (sugars and proteins).

The great Russian chemist Meldeleyev (who invented the Periodic Table of the Chemical Elements) was a pioneer in his opinion that petroleum was of "mineral origin", he thought by the action of water on iron carbides deep in the earth. It is fascinating that in DHB, Gold describes an experiment he undertook in which a borehole was drilled-out in central Sweden, through crystalline bedrock down to a depth of 5 kilometers. 80 barrels of oil were recovered, but also significant quantities of a material called magnetite. Now magnetite is a reduced form of iron oxide (Fe3O4) compared to Fe2O3, the normal mineral form. [Put another way, in Fe3O4, twelve Fe atoms would need sixteen oxygen atoms to balance them, whereas in Fe2O3, twelve Fe atoms need an eighteen O atom counterweight]. Gold advances the theory that bacteria present at depth (The Deep Biosphere) use Fe2O3 to oxidise petroleum as a process from which to extract their energy, thus producing CO2, H2 + Fe3O4. Ingenious!

Gold also speculates that natural gas (methane), petroleum and coal represent materials formed by an increasing loss of hydrogen, and so coal, along with gas and oil, should be an inexhaustible resource since it too is created continually. He also speculates that earthquakes might, in some case, be due to upwellings of gas and thus occur even in regions well away from tectonic plate boundaries. He further cites examples where "barren" oil wells have spontaneously "refilled", he believes from depth, although I have spoken to experts in the oil industry who thought that this was merely due to near-surface oil of biological origin percolating through strata and into the empty space.

I found these books fascinating and well worth reading. To my mind the idea that gas, oil and coal may be formed by some continual actions intrinsic to the earth's geochemistry is a paradigm shift. If it is proved true, the Russian geologists would probably find it less so, saying "we knew this all along, but you wouldn't listen to us!"

However, even if it is true, what does this mean in terms of peak oil (or peak gas or coal for that matter)? It might appear, as Gold says in DHB, that there is nothing to worry about and it is all a hoax. He even cites evidence that the great oil fields of Saudi may be refilling from elsewhere, he thinks from below. However, this only matters to the utterly pressing challenge of meeting our present and rising demand for oil if such wells refill (or more can be dug through deep boreholes, down below 5 kilometers, say), fast enough to draw-up oil at a matching rate. For the sake of argument, if the Saudi wells refill, but it takes 100 years to do so, this will not help us one iota in balancing the production shortfall in oil that is believed to begin within about 5 years. I also think that the deep-drilling projects might be hampered if the oil that is presently down there is matched in quantity by magnetite which will probably clog-up drills, pipes and so on.

I recommend both DHB and JE, out of pure scientific and philosophical interest but I remain unconvinced that we are out of the woods yet!

Related Reading.
(1) "The Deep Hot Biosphere", by Thomas Gold, ISBN: 0-387-95253-5, Copernicus Books, 2001. (Available from Amazon.com and Amazon.co.uk).
(2) "Jagged Environment", by Chris James, ISBN: 0-954-00940-1, JEpublications, 2001. (Available from Amazon.co.uk but not Amazon.com... How strange?). Or from http://www.jaggedenvironment.com

No comments: