Black Gold

A discussion for the geologists and roughnecks out there:I have been reading about the Guadalupe Mountains and El Capitan in Texas as I may visit there in a couple of weeks. El Capitan is a thousand foot limestone cliff, which geologists believe is from the Permian Era (about 250 Mya).There is also a large permian oil resevoir near the area. I have read from several sites that this oil resevoir is formed from buried plant and animal material that was heated and compressed. I have also heard several members of this site say something to the effect that this is how oil is formed. I have a few problems with this explanation.What would cause such a vast amount of plants and animals to be buried rapidly enough to produce the carbon for this oil?I have heard the creationist argument that since oil resevoirs exist in permiable rock at such high pressures, they must be young or else the pressures would have dissipated over the millions of years. What is the uniformitarian explanation?Finally, I read an article not too long ago from World Net Daily about the alternative theory of oil formation. It started off by giving an example of an oil well on top of the Mississippi river delta in the gulf. This well pumped out 15,000 barrels a day when it was first tapped in the 70's. Production slowly declined over the years to less than 5000 barrels a day. The company was about to abandon the well as it was becoming no longer profitable when the well refilled itself and began pumping out 15,000 barrels a day again. The article said that this phenomenon has been observed in many wells world-wide.My Dad, who is a geologist, recalled that when he took his courses in geology (over 30 years ago), the professor remarked that due to the heat and pressure necessary for oil to form, the formation of oil is largely a mystery. This article also pointed out that the heat and pressure necessary to produce oil is only found near the earth's mantle. This has led to the theory that methane in the earth's crust is heated and condensed into crude oil near the mantle and then finds its way into the upper crustal rock. This is supported by the fact that an isotope of Helium, a radioactive decay product, is almost always found with oil. In fact, this Helium is used to sniff out oil wells.The article went on to say that for the last 25 years this theory has been circulated and accepted by most oil companies as the means by which oil is formed. So oil may be a renewable resource after all, and it may not take hundreds of millions of years to form as is stated by everything I've ever read about it.If this is the case, why is there so much misinformation out there about how oil forms? If this is not the case, then what are the typical explanations for these things?

Thread moved here from the Proposed New Topics forum.

Hold on a minute!Is it the done thing for the admin version of a poster to approve their own topics?(I actually don't know, that is why I'm asking!)It's like the editor of a peer-reviewed journal clearing his own stuff.moreover, a 3 minute gap between posting and approval does not suggest a very in-depth investigation of the merits of the topic!Indeed you discuss a number of articles and yet provide no links to them - surely a suggestion for improvement that an admin would make before "releasing" this topic.This message has been edited by Charles Knight, 07-28-2004 06:11 PMThis message has been edited by Charles Knight, 07-28-2004 06:12 PM

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Is it the done thing for the admin version of a poster to approve their own topics?

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Yeah. NosyNed did the same thing in another forum. I really don't have a problem with it. Once someone is given the title of Admin(insert name), it is agreed that they understand the requirements for an opening post. Plus, it is rare for a creationist to open a thoughtful thread so it probably shouldn't be discouraged, just on principle alone.

I know... I just thought about that after I moved my own topic... I spose that's not how it works!My bad... I won't do it again. I'm still new to this moderating business... Actually, I only refer to one news article from WND, which I read a couple of months ago or more, so I'm not even sure if it's still available on the net, but I do recall the article quite well.

But I Don't recall the article!

You post suggests at least two sources "I have been reading" and finally I read an article .Can you provide any sources to kick the debate off?

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What would cause such a vast amount of plants and animals to be buried rapidly enough to produce the carbon for this oil?

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Who said it had to be rapid? What you are forgetting is that oil does not stay where it is formed. Instead it perculates down into the ground, often taking up the spaces between particles in sedimentary rock (such as oil shales). An oil "well" is not a vast, open cavern filled with hydrocarbons, but an area of porous material that holds oil under pressure. Once that pressure is released then the oil shoots to the surface.

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I have heard the creationist argument that since oil resevoirs exist in permiable rock at such high pressures, they must be young or else the pressures would have dissipated over the millions of years. What is the uniformitarian explanation?

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My geologic knowledge is pretty shaky, but if I remember correctly the oil wells are surrounded by rock that holds the oil in so that it can't escape. Think of it as mud kept in a cement ditch. The pressure can't escape because there is nowhere for it to escape to.The rest I will have to read up on, or leave it for the local geology experts (eg Bill Berkland). Like I said, don't take my word as gospel (pardon the pun).

DAWGI read the same article about the potential of Oil being renewed, but I gathered that it was not so much a matter of new oil being created as the resovoir refilling.I'll see what I can find on it and post links when I find them.One thing you need to remember though, regardless of the original source of hydrocarbons, it does not mean they were all in one pocket originally. What happens is that the oil tend to seep through the more porous rocks and collect in quantities at certain points, places where some less porous rock stops the seepage and acts as a barrier.

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Aslan is not a Tame Lion

I found the WND article. It can be viewed here:Page not found - WND

I have wondered about that myself. I posted a proposal and left it but no one else commented so I approved my own proposal.I think that if we trust someone to administrate then we trust them not to create topics of complete junk. There hasn't been a problem as yet.I would have approved this thread myself if I'd gotten to it first.

This much I am sure of. That is correct. Oil "wells" are a volume of permiable rock capped by impermiable rock. That comment is enough to make me wonder just how well researched that article was.Even an armchair amateur knows that much about petroleum geology.

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He also notes that oil extracted from varying depths from the same oil field have the same chemistry — oil chemistry does not vary as fossils vary with increasing depth. Also interesting is the fact that oil is found in huge quantities among geographic formations where assays of prehistoric life are not sufficient to produce the existing reservoirs of oil. Where then did it come from

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This suggests to me that the author of this article thinks that the oil is where it was formed. I was taught otherwise a long time ago. It wouldn't be in highly localized places that are of just the right form to trap it if that was true.Because of the mixing we wouldn't expect there to be an age/depth correlation that the article suggests.The article supplies no primary references. I am very suspicious of that.If the "traping" mechanism is correct as I recall it then the possibility of refilling becomes fairly obvious and I don't understand why it is such a mystery. But then I'm not an oil geologist.The WSJ article referenced is 1999. There was money allocated for funding research into this. I keep up with a range of things. Any further progress on this has escaped my notice. Do we have anything more up-to-date? It seems there are some interesting speculations here but nothing more.Again no primary references are given.My crank-o-meter wiggles when I note that a lot of money is involved here: Hundreds of billions. And this sinks without any particular splash 5 years later?

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There is also a large permian oil resevoir near the area. I have read from several sites that this oil resevoir is formed from buried plant and animal material that was heated and compressed. I have also heard several members of this site say something to the effect that this is how oil is formed. I have a few problems with this explanation.

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What would cause such a vast amount of plants and animals to be buried rapidly enough to produce the carbon for this oil?

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Well, this is a longer story that I care to tell, but perhaps a quick summary is possible. All that is necessary for sediments high in organic material to form is a low input of terrigenous and chemical sediment, and a long-lived prolific environment for organic remains to accumulate. This is not speculation. We see it happening today in various types of environments.The next thing to remember is that oil doesn't just form, it migrates. That means that it can accumulate in rich zones even though the source may be a bit lean.

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I have heard the creationist argument that since oil resevoirs exist in permiable rock at such high pressures, they must be young or else the pressures would have dissipated over the millions of years. What is the uniformitarian explanation?

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Nope. Oil is being continuously created in the sedimentary basins and migrating into different reservoir rocks, or even to the surface.

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Finally, I read an article not too long ago from World Net Daily about the alternative theory of oil formation. It started off by giving an example of an oil well on top of the Mississippi river delta in the gulf. This well pumped out 15,000 barrels a day when it was first tapped in the 70's. Production slowly declined over the years to less than 5000 barrels a day. The company was about to abandon the well as it was becoming no longer profitable when the well refilled itself and began pumping out 15,000 barrels a day again. The article said that this phenomenon has been observed in many wells world-wide.

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No problem at all. Compacting sedimentary basins are always creating new pathways for oil to migrate. This is especially true where subsidence is aided by pumping and/or tectonism.

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My Dad, who is a geologist, recalled that when he took his courses in geology (over 30 years ago), the professor remarked that due to the heat and pressure necessary for oil to form, the formation of oil is largely a mystery.

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Actually, there are some very good explanations with evidence of actual intermediate steps.

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This article also pointed out that the heat and pressure necessary to produce oil is only found near the earth's mantle.

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Nonsense.

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This has led to the theory that methane in the earth's crust is heated and condensed into crude oil near the mantle and then finds its way into the upper crustal rock. This is supported by the fact that an isotope of Helium, a radioactive decay product, is almost always found with oil. In fact, this Helium is used to sniff out oil wells.

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Well, then explain where the methane came from, especially since isotopic evidence indicates an organic origin. But again, while this may be possible, it is unnecessary since we know that the more refactory organic materials stay behind in the source rocks.

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The article went on to say that for the last 25 years this theory has been circulated and accepted by most oil companies as the means by which oil is formed.

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NOt that I have heard of.

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So oil may be a renewable resource after all, and it may not take hundreds of millions of years to form as is stated by everything I've ever read about it.

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This is very poor logic. First, we know that many oil fields have been played out. Second, there still has to be a source for the methane and how you transport it to depth.

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If this is the case, why is there so much misinformation out there about how oil forms?

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Simple, it isn't true.

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If this is not the case, then what are the typical explanations for these things?

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There are many and diverse explanations, all well within the possibilities of an old earth and organic origins for oil.

Our good Mr Birkeland will probably be along soo to give some real documentation and knowledge, but I'll throw in a little I know from working around the "awl bidniss" for a while now.The deep methane ideas are those of Thomas Gold, a polymath, maverick sort of guy who died just a month ago at 84. He worked with Hoyle, Bondi, and other big-name physicists and astronomers at various times. His ideas may have some merit - the deep gas in western Oklahoma was found by people who listened to him. But so very much petroleum has "biomarker" molecules in it that can be directly related to living things, even specific kinds of algae, or the cuticle on a kind of leaf, that I'm pretty well convinced that most oil is biogenic. A lot of natural gas may well not be, but that's not to say it's "primordial." There might be oxidation/reduction reactions in hot rock that could produce methane.The "leaky caprock" bit turns up pretty often on creato sites, but I've never seen references or even numbers for the supposed "too-high" permeability of caprock. I strongly suspect that the permeabilities this claim is based on could be from cores from wells that were treated the standard way reservoir cores are: cleaned of oil, dried thoroughly, and perm measured with dry nitrogen at near-atmospheric pressure. That actually gives a pretty decent number for a highly permeable, clean sandstone, but may not in other cases. I remember a case of a tight gas sand in the Rockies that measured, say, one millidarcy under those conditions, but 0.001 millidarcy when confined at the pressure that the reservoir was actually at. (The wells didn't produce up to expectations at first.....) It may be that similar measurments on capping shales misled someone - a dried-out shale that's been depressurized from 10,000 psi to atmospheric is not in it's native state any longer, and those very low permeabilities aren't anything simple to measure accurately anyway. One invisibly small crack could easily let more nitrogen through that the matrix of the whole core surrounding it.Reservoir rock having been hot (100 or 150 degrees C, for example) is not just a guess, either. For just one indicator,there's a substance called vitrinite that changes color depending on it's heating history - geologists use it to see if source rocks have been hot enough (or too hot) for optimal oil generation. Hmmm. Where? I might want to invest.....
That happens a lot when humans intervene, like when waterflooding old reservoirs, but I've never heard of it just happening.