From the UNIVERSITY OF WISCONSIN-MADISON, comes this study sure to cause some left-leaning anti CO2 heads to explode. The bold in the PR is mine.
Fossil fuel formation: Key to atmosphere’s oxygen?
Oxygen enables the chemical reactions that animals use to get energy from stored carbohydrates — from food. So it may be no coincidence that animals appeared and evolved during the “Cambrian explosion,” which coincided with a spike in atmospheric oxygen roughly 500 million years ago.
It was during the Cambrian explosion that most of the current animal designs appeared.
In green plants, photosynthesis separates carbon dioxide into molecular oxygen (which is released to the atmosphere), and carbon (which is stored in carbohydrates).
But photosynthesis had already been around for at least 2.5 billion years. So what accounted for the sudden spike in oxygen during the Cambrian?
A study now online in the February issue of Earth and Planetary Science Letters links the rise in oxygen to a rapid increase in the burial of sediment containing large amounts of carbon-rich organic matter. The key, says study co-author Shanan Peters, a professor of geoscience at the University of Wisconsin-Madison, is to recognize that sediment storage blocks the oxidation of carbon.
Without burial, this oxidation reaction causes dead plant material on Earth’s surface to burn. That causes the carbon it contains, which originated in the atmosphere, to bond with oxygen to form carbon dioxide. And for oxygen to build up in our atmosphere, plant organic matter must be protected from oxidation.
And that’s exactly what happens when organic matter — the raw material of coal, oil and natural gas — is buried through geologic processes.
To make this case, Peters and his postdoctoral fellow Jon Husson mined a unique data set called Macrostrat, an accumulation of geologic information on North America whose construction Peters has masterminded for 10 years.
The parallel graphs of oxygen in the atmosphere and sediment burial, based on the formation of sedimentary rock, indicate a relationship between oxygen and sediment. Both graphs show a smaller peak at 2.3 billion years ago and a larger one about 500 million years ago.
“It’s a correlation, but our argument is that there are mechanistic connections between geology and the history of atmospheric oxygen,” Husson says. “When you store sediment, it contains organic matter that was formed by photosynthesis, which converted carbon dioxide into biomass and released oxygen into the atmosphere. Burial removes the carbon from Earth’s surface, preventing it from bonding molecular oxygen pulled from the atmosphere.”
Some of the surges in sediment burial that Husson and Peters identified coincided with the formation of vast fields of fossil fuel that are still mined today, including the oil-rich Permian Basin in Texas and the Pennsylvania coal fields of Appalachia.
“Burying the sediments that became fossil fuels was the key to advanced animal life on Earth,”
Peters says, noting that multicellular life is largely a creation of the Cambrian.
Today, burning billions of tons of stored carbon in fossil fuels is removing large amounts of oxygen from the atmosphere, reversing the pattern that drove the rise in oxygen. And so the oxygen level in the atmosphere falls as the concentration of carbon dioxide rises.
The data about North America in Macrostrat reflects the work of thousands of geoscientists over more than a century. The current study only concerns North America, since comprehensive databases concerning the other 80 percent of Earth’s continental surface do not yet exist.
The ultimate geological cause for the accelerated sediment storage that promoted the two surges in oxygen remains murky. “There are many ideas to explain the different phases of oxygen concentration,” Husson concedes. “We suspect that deep-rooted changes in the movement of tectonic plates or conduction of heat or circulation in the mantle may be in play, but we don’t have an explanation at this point.”
Holding a chunk of trilobite-studded Ordovician shale that formed approximately 450 million years ago, Peters asks,
“Why is there oxygen in the atmosphere? The high school explanation is ‘photosynthesis.’ But we’ve known for a long time, going all the way back to Wisconsin geologist (and University of Wisconsin president) Thomas Chrowder Chamberlin, that building up oxygen requires the formation of rocks like this black shale, which can be rich enough in carbon to actually burn. The organic carbon in this shale was fixed from the atmosphere by photosynthesis, and its burial and preservation in this rock liberated molecular oxygen.”
What’s new in the current study, Husson says, is the ability to document this relationship in a broad database that covers 20 percent of Earth’s land surface.
Continual burial of carbon is needed to keep the atmosphere pumped up with oxygen. Many pathways on Earth’s surface, Husson notes, like oxidation of iron — rust — consume free oxygen.
“The secret to having oxygen in the atmosphere is to remove a tiny portion of the present biomass and sequester it in sedimentary deposits. That’s what happened when fossil fuels were deposited.”
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Rud, Upland topsoils, soil not in a floodplain, in the presence of adequate moisture,
owe their richness to the amount of natural gas up welling through them.
I tested, I did not model or theorize.
Lets do a test.
Yup, that plate tectonics theory is nuts! Whoever heard of moving continents? utter nonsense!
To be fair to geologists before c. 1960, it was continental drift which they found nuts. Once plate tectonics was established, and the mechanism for “drift” discovered, ie sea floor spreading, the Old Guard fell into line sooner than they did for the Missoula Floods and similar massive outbursts from ice-dammed lakes (jökulhlaup).
True, but consider all of the evidence which was pooh-poohed for many decades prior to the discovery of the mid-oceanic ridges.
The close match of the continental margin alone would be an impossible coincidence. The fact that, when the continents are lined up according to these matching margins, there happen to be identical rock strata, with identical fossil sequences does, IMO, constitute proof.
One has to be willfully ignorant to disregard this evidence. Rather than discarding the idea because no mechanism was known, a mechanism could have or should have been sought, rather than marginalizing anyone who argued the evidence.
The entire story is a very good illustration of how so-called experts are often anything but real experts…that they often are and have been blind to truth and unbending in their dogma.
Ultimately all of the carbon on Earth is from the dust and gas that the Sun and planets condensed from (apart from a little from carbonaceous chondrites since). Likely the carbon was in the form of methane as that molecule seems to be prevalent in space (where did the methane on Titan come from?) Some of it got trapped under the crust and in the mantle and being lower density than its surroundings will percolate to the surface. For life to use it it had to first arrive in regions where life molecules could survive (deeper than you’d think at first).
So it’s a no brainer that ALL the carbon is from inorganic sources. Life may have used some of it along the way and left evidence.
Presence of fossils or microbes in oil is not proof that the oil was formed by living matter which died. Your average microbe on encountering oil probably thinks: “yum! unoxidised carbon and hydrogen!”
ladylifegrows, read some of the late Tommy Gold’s books on the subject. He was not at all dogmatic, was open to being proved wrong and proposed some experiments for up and coming geologists. I haven’t heard if anyone has done them.
If the mechanism I described was happening in the primordial Earth, when did it stop? if it didn’t stop it is still happening and AFAIK experimental evidence exists of abiotic formation of longer chain hydrocarbons from methane under conditions found deep in the Earth.
I suggest reading “The Deep Hot Biosphere, The Myth Of Fossil Fuels”, by Thomas Gold, with a Foreword by Freeman Dyson. ISBN 978-0-387-95253-6.
Thomas Gold was fluent in Russian and appears to have plagiarised the Russian/Ukrainian theory of abiotic oil and gas production adding in some additional (possibly incorrect) thoughts. If you have time it is well worth reading and following the links at http://www.gasresources.net/introduction.htm which give a very thorough layman’s introduction for anyone prepared for a bit of work. There are a few complicated bits but these can be lightly skipped over without losing the thread of the argument. It is well worth bookmarking and reading when time permits. Warning, if you are curious, the introduction might ensnare you to spend time you hadn’t planned!
I am astonished that Ristvan, whose comments I have read for years and been impressed by his apparent knowledge, should think that “the science is settled” on this topic. I can’t believe that he thinks there is no calcium carbonate, iron oxide and water being subducted into the mantle. The link above gives details of experimentation which demonstrate that at the temps and pressures at that depth, chains of hydrocarbons found in crude oils are the natural, stable result from just these three common materials. They could then be brought nearer the surface and trapped, waiting to be found in much the same way as diamonds are.
SteveT
Rocks dude rocks…. Everything is chemically bonded in rocks.
Ristvan, who is usually very sensible and thoughtful and well informed really missed on the photosynthesis-O2 source (water, not CO2)….as soon as I read his comment, I did a “yikes, don’t think so”
The last quote in the article reads: ““The secret to having oxygen in the atmosphere is to remove a tiny portion of the present biomass and sequester it in sedimentary deposits.”
Sounds to me like an endorsement for landfilling our waste instead wasting so much time (and energy) sorting it out.
2 points.
First – not only does O2 come from water but the light phase of photosynthesis is relatively independent of the dark phase. The hydrogen from water, along with the electrons, is stored in the form of two high energy carriers, When these reduced carriers are too high in proportion to the oxidised forms then the energy is wasted by side reactions in order to restore some of the oxidised forms.Typically most plants waste about 50% of the energy gained by these carriers so that the rate at which oxygen is formed is about double that needed to produce the carbohydrate formed in the dark phase.
Secondly, if one looks at oxygen levels from mid Devonian to the Permian, they rose from 15 to 25% coinciding with the decline in atmospheric CO2 but after CO2 had stabilised at around 300 ppm, O2 continued to rise steeply from 25 to 35% coinciding with the beginning of the Ice Age around 320 mya.
I suspect that this was due to ice sheets covering the land and preventing eroded iron from reacting with oxygen. That is, plants continued to produce oxygen from photosynthesis but its removal by oxidation of minerals was hugely reduced allowing oxygen to accumulate.
At the end of the ice age at 275 mya O2 plummeted back to 15% as the ice uncovered the minerals.
This started the extinctions, loss of atmospheric oxygen then allowed sulphur bacteria to produce hydrogen sulphide so that the already anoxic oceans became poisoned, accelerating the extinctions.During this time CO2 increased mainly from decomposition of the dead. The Siberian traps volcanoes did not start until near the end of the extinctions.
The key point of all of this is that oxygen dropped so dramatically because there was not enough CO2 in the air. Plant growth, slowed and inhibited by low CO2, was insufficient to maintain oxygen levels.
The great Permian extinction did not happen at 252 mya, it had been accelerating for some 15 million years before that. The extinctions ended at 252 mya when CO2 was rising through the 1600 ppm mark. The Increasing CO2 levels allowed increased plant growth that first slowed the decline in oxygen and then, several million years later reversing it.
This is the lesson for today when once again plant growth is slow due to low CO2 and oxygen is declining because oxidation exceeds the capacity of plants to replace it.
CO2 is the most important molecule for life on Earth. Without CO2 there are no plants, without plants there is no photosynthesis, without photosynthesis there is no food and there is no oxygen.Without those, higher life forms cannot exist.
I find it very surprising that in such a paper, which explores the how and why carbon was sequestered in increasing amounts during the carboniferous period, no mention is made of the reason why the carbon was became so difficult to oxidize…the development in plants of cellulose and especially lignin, and that is took a very long time for other life forms to develop the enzymes need to break these down.
In those days, plants had far more lignin, many times more, and it was impervious to biological decomposition for many millions of years.
I wonder if the authors are unaware of this basic fact?
@Rud For your enjoyment—-Horsehead nebula and hydrocarbons.
http://annesastronomynews.com/the-horsehead-nebula-is-a-cosmic-petroleum-refinery/
I thought that calcium carbonate, limestone, deposited on the sea floor was where most carbon was sequestrated.
Perhaps the rate at which carbon comes out of volcanoes is not constant?
Tim, The sea floor is where most carbonates are sequestered. The layers that you see
as you descend the Grand canyon are mostly carbonates, 200+ million years worth.
volcanoes do not recirculate it nearly fast enough to keep CO2 levels in the atmosphere
to support life as we know it on earth.
Up welling hydrocarbons being oxidized by microbes, enriching the topsoil as they die,
or hydrocarbons escaping into the atmosphere to be oxidized there are the mechanisms
which give the atmosphere adequate CO2.
v’