Coal is said to be compressed plant matter, carbonized by millions of years of heat and pressure. In essence, it is peat which has been carbonized. yet, some oil geologists say that coal is actually carbonized crude oil-that is oil with all of the volatile compounds driven out-is this possible? Does any DNA remin (of the plants which formed it) in coal beds? and, do oil and coal deposits ever occur next to eachother?
I’ve wondered if coal might possibly be naturally-occuring carbon deposits. We mine iron ore, aluminum ore, copper ore, and all sorts of other elements. Do we really know for a fact that coal isn’t just carbon ore?
One type of coal that’s common in the Lancashire fields (i.e. right under Wigan) contains an abundance of fossil ferns etc. I think it’s beyond doubt that coal is derived from plant matter.
No. I’m going to invoke the name of Una Persson, who can explain it much better than I. But somewhat different modes resulted in the forming of the two “fossil hydrocarbon” deposits. Don’t forget that there is a spectrum of increasing carbonification from peat through lignite and brown coal, subbituminous and bituminous coal, through anthracite to metaanthracite. Crude oil seems to occur when capped anticlines allow concentration of liquid volatiles from decayed organic matter in one place. Aside from western Pennsylvania historically, I’m not familiar with anywhere where they tend to form in the same general location, though both require beds of sedimentary rock.
In many coal seams you can find the fossilized imprints of leaves, twigs, and in a few cases entire trunks of the flora of the Carboniferous period. Oil is formed, then percolates through layers of porous rock until it finds a high spot where overlying strata allow it (and the gasses associated with it) accumulate. It is an entirely different process.
Prior to the end of the carboniferous period, according to some theories, there were no bacterial species that could break down lignin, the substance that makes wood woody. Even today there are only a dozen or so basic genera that do so, most of them living within the gut of termite species. So, the masses of carbon sequestered in the woody stems of the forests of the times accumulated on a geologic scale, rather than an ecosystem time scale.
I don’t know of any coal deposits that don’t fit within that pattern.
Tris
There are several stages to oil production.
Stage one involves the deposition of organic matter in an anoxic (no oxygen) environment.
The same is true for coal, plant matter laid down with no oxygen, typically thought to be in swampy environments.
Satge 2 The organic material is then burried and heated.
Some of this will turn to coal depending on the correct environment.
The coal deposits will be found in their original beds
Stage 3 for teh stuff destimned for oil involves further heating and pressuring of the organic material into something known as kerogen - a basic hydrocarbon soup. See here
http://www.glossary.oilfield.slb.com/Display.cfm?Term=kerogen
Kerogen comes in several types and will typically produce different types of hydrocarbon.
The kerogen located in shaly type rocks is heated away for a couple of million years and turns into bitumen, oil, condensate and gas.
The cooked products then migrate through the rock to either surface or become trapped in a sealed area of rock which gets called a reservoir. These are sand stones, limestones, dolomites and old burried coral reefs.
I have seen references to coal being made from kerogen but never coal from oil.
Coal beds are certainly found near oil reservoirs and indeed nodules of coals can be found in reservoirs (the North Sea Brent group of formations is one that springs to mind), although the prescence of the coal is incidental to the prescence of the oil, as the oil has migrated from elsewhere.
Both coal and oil production and extraction takes place in sedimentary basins so it is not surprising that they will be found togeather.
In short;
Oraganic material to coal
or
Organic material to kerogen to bitumen / oil
or maybe
Organic material to kerogen to coal (would need to dig some on this, maynot be coal as is typically thought of. There is a coal expert hanging around the board somewhere who will no doubt be along shortly to suggest I lay off the hard drugs).
but not
Organic material to kerogen to oil to coal
cheers
NBC
And as ever
Which indicates that type III kerogen typically becomes coal
We don’t know for sure, but it is very much a minority opinion amongst geologists. Of course being aminority opinion doesn’t make it wrong.
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It’s correct to say that most genera of ligin degraidng fungi are represented as termite gut flora. It is in no way correct to say that most genera live as gut flora. That’s a pretty significant difference. Most human populations are represented in France. That doesn’t allow us to say that most human populations live in France.
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Even today bacteria aren’t very significant in the breakdown of ligin for purely mechanical reasons. That is a role filled primarily by fungi and protists. It would be very hard to believe that fungi and protists, many of which produce cellulose and some of which produce lignin for their own cell walls, were ever unable to degrade lignin.
While I like the vote of confidence, I’ve arrived too late to this thread to add anything of interest or value. I’ll note only that the exact origins of most specific coal beds are still somewhat of a mystery, although the general coalification process is decently well accepted by science. This gives young Earth folks enough of a fingerhold to obfuscate the issue, unfortunately.
BlakeThanks for fighting my ignorance. I suppose my information is very out of date. Got a reference on line where I can pick up more about it?
Tris
Thanks for the info. I didn’t know you could find fossil imprints in coal. The “carbon ore” idea was just a thought that occurred to me a while back.
What about the DNA question? Does DNA from the plants remain?
Don’t forget oil shale.
It’s not economical to extract oil out of it now (Exxon tried it in Colorado for years), but the oil in the US’s oil shale rivals liquid oil fields around the world.
It’s been reported that it is economical with oil prices exceeding $50 a barrel.
What happened to the abiogenic oil theories and did any of those cover coal as well?
I have some coal fossils somewhere - they’re quite difficult to take a photo of, otherwise I’d post them.
While I’m sure there are some followers, I’ve not really run across any large number of folks proposing abiogenic coal. Most of the more out-there theories involve (the) great flood(s).