The evidence that he puts forward is basically five-fold, but has just raised yet more questions in my mind. If any scientists read this, I would be interested to know the answers to the questions posed: especially the ones about chirality. So, the evidence is this:
- Point: there is evidence that abiotic methane—required to form any abiotic oil—is manufactured deep in the earth. We see it coming up from vents underwater, and also seeping through the rocks in deep mines. However, there simply isn't enough to form the vast deposits seen in oil fields and the like.
Questions: if large amounts of methane or oil are produced deep in the planet, the idea is that the majority of this then seeps through large, existing faults into the large underground caverns that we draw hydrocarbons from. Since this is the path of least resistance, then surely we would surely expect the vast majority of any abiotic hydrocarbons to end up in these wells, rather than seeping through deep, hard rock mines, etc. which are areas of higher resistance? How, then, can we decide that those expulsions that we do see show us that too little abiotic hydrocarbons are produced underground? And how do we know that these hydrocarbons are being produced at the same level as those that end up in the wells?
- Point: the transformation between abiotic methane and the many different long-chain hydrocarbons in oil is a massive leap chemically, and thus probably impossible as far as has been tested in lab conditions.
Questions: the depths of the earth are pretty unknown territory: what do we know about such areas that allow us to deduce that such reactions—whilst vanishingly unlikely in lab conditions—are not entirely possible when considering such an environment and a still reasonably long timescale?
- Point: this is the point about chirality and optical isomers. Most hydrocarbons formed by organic processes shift polarised light to left, whilst most abiotic hydrocarbons shift said light to the right. Most of the oil found shifts polarised light to the left, and is thus organic in origin.
Questions: why is this the case? It has been a long time since I studied organic chemistry (and I was very bad at it: had I not been, I would be a practising doctor by now) and cannot recall everything about chiral properties. However, is it not the case that these chiral properties are induced through the method of manufacture? Or is it the case that there is something inherently different about the carbon atoms in lifeforms on this planet that induce such a distinction in the organic carbon atoms themselves? Does this then mean that there are a limited number of carbon atoms on the planet from which all organic life is formed? Or, if it is the method of manufacture, what factors enable this distinction between organic and inorganic manufacture?
- Point: we know that organic matter can be carried deep into the earth's crust, because we have observed garnets within the pipes that diamonds appear in. The diamonds could only have formed at massive temperatures and pressures deep in the crust, but garnets could only have come from the surface.
Questions: this is all true. However, a garnet is considerably more durable that the average organic body. Given the scraping of the tectonic plates and the vast pressures present when edges are subsumed, surely the organic matter would have to be in a rock-like state in order not to be simply scraped off onto the opposing plate? Is the organic matter then taken into the crust and turned into oil through massive temperatures?
- Point: we know that bringing garnets down through the Earth, forming diamonds and then spewing them up again takes a very long time but—look!—there's a star that probably exploded 440 million years ago. So things have been around a long time. Our planet is 4.5 billion years old and this is more than enough time to get some organic matter, pop it down into the crust and then bring it up again.
Questions: this last bit is the silliest point, really. Although our planet has been around for some 4.5 billion years, organic life has probably existed for around 3.5 billion years. If we need special carbon atoms for the chirality argument, where did they come from? And if the chirality is based on the way in which the molecules are manufactured, where did the first chiral isomers come from?
If the Earth has been around for billions of years, then why—even if abiotic methane seepage is as minor as posited here—could not have accumulated over that vast amount of time? After all, under the abiotic theory, the methane has had about 1 billion years extra to accrue and react than in the organic cycle (of course, if any abiotic route were that slow, then it's of little practical use to us right now).
I am not subscribing to the abiotic theory at all but I do believe that the explanations for why it could not happen this way raise an awful lot of questions. So, can anyone answer any of these questions? You have one hour and you may turn your exam papers over... now!
In the meantime, I am going to look at the organic formation method and raise similar questions about that. But first, maybe some politics...