Where does Oil come from?

[Dabljuh]

Why make that distinction?



How hard did you look? How about this and this ?

Is that the rule or the exception?

Why do they need to be more likely in coal than limestone? Both coal and limestone are sedimentary rocks, primarily composed of dead organisms.

coal is a sediment? Based on the biogenic origin theory, which requires it to be a sediment? Circular reasoning, it seems to me.

I do hope you're not living up to your sig.

I don't care about your opinion on this particular issue.

Alright, different: What is so incredible about carbons and carbohydrogens simply ocurring in the earth's crust and mantle without a biological reason? I'm not saying *none* is, but probably the overwhelming majority?

 

[Mojo]

Alright, different: What is so incredible about carbons and carbohydrates simply ocurring in the earth's crust and mantle without a biological reason?

You need to check out the difference between carbohydrates and hydrocarbons, by the way.

I seem to remember Velikovsky having this problem as well.

 

[Dabljuh]

Right, carbohydrates have hydroxyl groups in them. Its a linguistic thing for me, "Kohlenwasserstoffe" vs "Kohlenhydrate", a syntactic equivalent is missing in english ("Carbohydrogen")

 

[Mojo]

Right, carbohydrates have hydroxyl groups in them.

And people don't generally attempt to sweeten their tea with paraffin.

They're different groups of compounds.

 

[Rolfe]

I just took Dabljuh off ignore for some entertainment value, and you know, guys, we really, really need a woo-woo version of the Stundies here.

I've never seen or heard of a fossil being found in coal. Aren't most fossils found in, you know, rocks?

And you find fossils in rocks too. So rocks are made from fossils too, not just coal? I don't think so.

Show me evidence of fossils in coal. Show me evidence of fossils being more likely in coal than in limestone. etc.

You couldn't make this up!

This from someone claiming to be "skilled above-average and aware of it". A bit like Malcolm Kirkman's claim to be a Mensa member with a law degree.

Rolfe.

 

[Dabljuh]

Rolfe, apparently you lack the mental facilities required to understand irony.

Rest: I don't know squat about geology or paleontology. Chemistry and stuff, yeah, but geology? I barely find my way to the grocery store which means I suck at geography as well.

But check out space. You'll find plenty of hydrocarbons in space. What's so improbable about hydrocarbons forming a part of a planet's crust without any life involved?

Obviously I was wrong and large amounts of "Rock", and quite possibly even petroleum, have indeed a biological origin. But still, my argument stands.

 

[I less than three logic]

This from someone claiming to be "skilled above-average and aware of it". A bit like Malcolm Kirkman's claim to be a Mensa member with a law degree.

Rolfe.

Could take the more cynical approach like myself and use this as evidence for just how bad average really is.

 

[zooterkin]

coal is a sediment? Based on the biogenic origin theory, which requires it to be a sediment? Circular reasoning, it seems to me.

Hardly; have you done even the barest amount of research on this topic? There is not a single type of coal, but several forms, and the development from peat is quite clear. From the wikipedia page:

As geological processes apply pressure to peat over time, it is transformed successively into:

* Lignite - also referred to as brown coal, is the lowest rank of coal and used almost exclusively as fuel for steam-electric power generation. Jet is a compact form of lignite that is sometimes polished and has been used as an ornamental stone since the Iron Age.
* Sub-bituminous coal - whose properties range from those of lignite to those of bituminous coal and are used primarily as fuel for steam-electric power generation.

* Bituminous coal - a dense coal, usually black, sometimes dark brown, often with well-defined bands of bright and dull material, used primarily as fuel in steam-electric power generation, with substantial quantities also used for heat and power applications in manufacturing and to make coke.
* Anthracite - the highest rank; a harder, glossy, black coal used primarily for residential and commercial space heating.
* Graphite - technically the highest rank, but difficult to ignite and is not so commonly used as fuel.

 

[Mojo]

Right, carbohydrates have hydroxyl groups in them. Its a linguistic thing for me, "Kohlenwasserstoffe" vs "Kohlenhydrate", a syntactic equivalent is missing in english ("Carbohydrogen")

Actually, there is an equivalent word in English, and it's in the post you were replying to. Why did you feel it necessary to edit "carbohydrates" in your earlier post to "carbohydrogens" when the correct word had already been supplied, and you had no trouble using it in your subsequent post?

 

[JoeTheJuggler]

Obviously I was wrong and large amounts of "Rock", and quite possibly even petroleum, have indeed a biological origin. But still, my argument stands.

So what's the argument?

Incredulity?

That there's "too much" petroleum to have been formed by fossilization of organic material?

Too much for what? Has someone calculated how much crude you get from a Permian forest? Or for that matter, the bulk of organic matter over a hundred million years or so?

You already pointed out that the only evidence for this extraordinary claim would be if people using the abiogenic theory of petroleum where better able to predict where to drill for petroleum, and they haven't been able to do so.

So what argument still stands?

 

[wilsontown]

Hm.

It's certainly true that some geologists have argued that some petroleum might be abiogenic in origin. Part of the reasoning behind this is that there are a surprising number of oil fields in fractured crystalline basement rocks. Most of these can be explained by normal processes of hydrocarbon migration and trapping. It's always possible that some small quantity of petroleum is abiogenic, but the evidence is that that proportion is vanishingly small.

 

[Rolfe]

Rolfe, apparently you lack the mental facilities required to understand irony.

When I want your opinion of my mental "facilities" I'll ask for it.

So are we to conclude that it's your very satisfied self-assessment in your sig that's the irony, or that the drivel you've just been posting about coal not containing fossils is intended to be irony?

Hint. Written material doesn't convery irony very well, and if you put a smug statement like that in your sig, it's likely to be taken literally.

Rolfe.

 

[Thabiguy]

Too much for what? Has someone calculated how much crude you get from a Permian forest? Or for that matter, the bulk of organic matter over a hundred million years or so?

Actually, the theory is that unlike coal, which formed from terrestrial plants (and then peat, lignite, etc.), oil ultimately formed from algae, plankton and other sea biomass (and then kerogen, bitumen, etc.).

Having said that, let's be generous and estimate the total known crude oil deposits in the world at 4 trillion barrels. Over a hundred million years, this works out to about 40,000 barrels, or about 5,000 tonnes deposited per year.

This is of course very tiny amount compared to the hundreds of billions tonnes of living biomass on Earth.

In fact, the biogenic theory has to account for this and actually explain why there is so little petroleum in the world! Naive calculations would predict much more of it.

The common explanation is that almost all dead sea biomass is eaten and only a fraction gets preserved under just the right conditions. And, in addition to that, even most of the crude oil that had formed in the past has also already been consumed by oil-eating bacteria.

 

[wilsontown]

To look at some of the stuff in the OP:

massive quantities of organic materials, that somehow ended up 100's of miles beneath earth's surface

Not 100s of miles. Up to a few km. And the 'somehow' bit is easy. The materials get buried during ongoing sedimentation.

But the amount of petroleum we're finding in earth's surface is simply way too much.

On what basis?

Wouldn't that energy-rich waste be consumed by microorganisms first?

Not if it gets buried quick enough.

Wouldn't the mechanics of plate tectonics more or less scrape an organic layer off a sea plate so never any more than minute quantities ended up under the crust?

If the organic layer in question was on oceanic crust, it might get subducted or obducted eventually. But there's no subduction at passive margins, so no problem. Also, plenty of the worlds oil/gas fields are on continental crust, where this would not be a problem (e.g. Middle East, UK North Sea).

Now, scientifically, you can't make a testable statement about the past.

I would disagree.

What you can do however, is using the alternative theory of the abiogenic petroleum origin, to predict where oil diggers would find oil. That the theory didnt have that much success is my only problem with the theory so far, but doesn't mean much because the method by which oil is searched for is far too chaotic.

So, your only problem with the theory is that it doesn't work. I think that's rather a large problem. How is the method by which oil is searched for far too chaotic? Trust me, there's an awful lot of money to be made in petroleum exploration. If there were good reasons to look for abiogenic oil, everyone would be doing it.

 

[bokonon]

I have entertained (and still entertain) this theory myself, while recognizing that it may be no more than wishful thinking.

It's true that abiogenic methane is abundant in the universe.

I believe it's also true that most petroleum is found near tectonic boundaries.

It's obvious that coal is a fossil fuel. I'm not sure I would argue the same for ALL petroleum.

I haven't studied the subject extensively, but I recall reading somewhere that the heat and pressure at extreme depths (i.e., 100 miles) would "crack" the molecules, making it unlikely or impossible for petroleum to exist there.

What about asphalt and tar? Are those also considered biogenic? Or are they a completely different substance, that couldn't be massaged into gasoline any more readily than uranium?

 

[wilsontown]

I haven't studied the subject extensively, but I recall reading somewhere that the heat and pressure at extreme depths (i.e., 100 miles) would "crack" the molecules, making it unlikely or impossible for petroleum to exist there.

100 miles is way, way deeper than any oil reservoir that is currently being produced. Hydrocarbons are found in sedimentary basins, in the top few km of the earth's crust. Given a geothermal gradient of 25 Celsius per kilometre and a pressure gradient of 1 kbar every three km, there's no problem having stable hydrocarbons at normal reservoir depths. There's a huge amount of study on this, as figuring out how hot your reservoir has been through geological time will tell you whether you are likely to find oil, gas or nothing at all.

100 miles would be way into the earth's mantle, and it simply isn't possible to drill to those kind of depths.

 

[Gurdur]

....Show me evidence of fossils in coal. .....

See here
and
see here

 

[Mojo]

Wouldn't that energy-rich waste be consumed by microorganisms first?

Not if it gets buried quick enough.

I think the theory is that it is deposited under anoxic conditions, which would limit the number of microorganisms that would act on it.

 

[Mojo]

You already pointed out that the only evidence for this extraordinary claim would be if people using the abiogenic theory of petroleum where better able to predict where to drill for petroleum, and they haven't been able to do so.

In view of the way oil migrates and collects in traps, would the abiogenic theory actually predict different results from the biogenic one?

 

[wilsontown]

I think the theory is that it is deposited under anoxic conditions, which would limit the number of microorganisms that would act on it.

That could work, although there is a lecturer in my department who is very sceptical of this idea. He's certainly looked at a lot of mudrocks, but there aren't that many people who find mudrocks interesting, so I'm not sure he gets the hearing he deserves.