300-million-year-old rainforest remnants discovered in coal mine - PeachParts Mercedes-Benz Forum

Botnst · #1 04-23-2007, 12:07 PM

300-million-year-old rainforest remnants discovered in coal mine
Jeanna Bryner
LiveScience Staff Writer
LiveScience.com

Mon Apr 23, 12:50 AM ET
Scientists exploring a mine have uncovered a natural Sistine chapel showing not religious paintings, but incredibly well preserved images of sprawling tree trunks and fallen leaves that once breathed life into an ancient rainforest.

Replete with a diverse mix of extinct plants, the 300-million-year-old fossilized forest is revealing clues about the ecology of Earth’s first rainforests . The discovery and details of the forest are published in the May issue of the journal Geology.

“We’re looking at one instance in time over a large area. It’s literally a snapshot in time of a multiple square mile area,” said study team member Scott Elrick of the Illinois State Geological Survey (ISGS).

Forest find

Over millions of years as sediments and plant material pile up, layer upon layer, the resulting bands become time indicators with the newest, youngest layer on the top and the oldest layer at the bottom. Typically geologists peel away a vertical slice of rocky material to look at material, including fossils, over a period of time.

A coal mine offers a unique view of the past. Instead of a time sequence, illuminated in the layer upon layer of sediments, the roof of an underground mine reveals a large area within one of those sediment layers, or time periods.

Miners in Illinois are used to seeing a few plant fossils strewn along a mine’s ceiling, but as they burrowed farther into this one, the sheer density and area covered by such fossils struck them as phenomenal, Elrick said.

That’s when they called paleobotanist Howard Falcon-Lang from the University of Bristol in the United Kingdom and William DiMichele, a curator of fossil plants at the Smithsonian National Museum of Natural History.

"It was an amazing experience. We drove down the mine in an armored vehicle, until we were a hundred meters below the surface,” Falcon-Lang said. “The fossil forest was rooted on top of the coal seam, so where the coal had been mined away the fossilized forest was visible in the ceiling of the mine.”

Forest snapshot

Here’s what the miners and other scientists saw underground: Relatively narrow passageways wind through the “cave,” marked off with stout 100-foot-wide pillars to ensure the roof doesn’t collapse.

“It’s like in some bizarre Roman temple with tons of Corinthian pillars that are 100 feet across and only six feet tall,” Elrick told LiveScience. “As you’re walking down these passageways you see these pillars of coal on either side of you and above you—imagine an artist’s canvas painted a flat grey and that is sort of what the grey shale above the coal looks like.”

The largest ever found, the fossil forest covers an area of about 40 square miles, or nearly the size of San Francisco. This ancient assemblage of flora is thought to be one of the first rainforests on Earth, emerging during the Upper Carboniferous, or Pennsylvanian, time period that extended from about 310 million to 290 million years ago.

A reconstruction of the ancient forest showed that like today’s rainforests, it had a layered structure with a mix of plants now extinct: Abundant club mosses stood more than 130-feet high, towering over a sub-canopy of tree ferns and an assortment of shrubs and tree-sized horsetails that looked like giant asparagus.

Flash freeze

The scientists think a major earthquake about 300 million years ago caused the region to drop below sea level where it was buried in mud. They estimate that within a period of months the forest was buried, preserving it “forever.”

“Some of these tree stumps have been covered geologically speaking in a flash,” Elrick said.

Because the spatial layout of the forest has been maintained, the scientists can learn about entire plant communities, not just individual plants.

"This spectacular discovery allows us to track how the species make-up of the forest changed across the landscape, and how that species make-up is affected by subtle differences in the local environment," Falcon-Lang said.

MTUpower · #2 04-23-2007, 10:14 PM

Send this over to the profs at the Colorado school of mines.....

t walgamuth · #3 04-23-2007, 10:37 PM

i heard this on npr this morning.

astounding!

cool.

tom w

Kuan · #4 04-24-2007, 03:20 PM

Heh, this is in Danville IL, possibly the lowest real estate values in the nation.

Their hotels are gonna be full of dusty geeks with headlamps!

#5 04-24-2007, 05:14 PM

This is the best thing to happen to Danville since the widespread use of methampetamines. I wonder if this will be open to the public sometime soon? I live a short drive away and would like to check this out.

Peter

t walgamuth · #6 04-24-2007, 10:28 PM

let us know, it is a short drive there from lafayette too.

tom w

mplafleur · #7 04-25-2007, 06:55 AM

Must of had global warming back then too.

Kuan · #8 04-25-2007, 07:07 AM

It's a long-ish drive from MO but doable. I doubt they'll let us in.

Botnst · #9 04-25-2007, 08:55 AM

Quote:

Originally Posted by mplafleur

Must of had global warming back then too.

Several times.

The Paleozoic is when the great coal and petroleum fields were deposited. Coincidentally, that is also when the CO2 concentration declined.

One question is this: What would happen if the sequestered carbon from the coal and oil fields was released back into the atmosphere? Not over millions of years, but over a couple of hundred?

Great experiment now in progress.

B

mplafleur · #10 04-25-2007, 09:10 AM

Quote:

Originally Posted by Botnst

Several times.

The Paleozoic is when the great coal and petroleum fields were deposited. Coincidentally, that is also when the CO2 concentration declined.

One question is this: What would happen if the sequestered carbon from the coal and oil fields was released back into the atmosphere? Not over millions of years, but over a couple of hundred?

Great experiment now in progress.

B

The effect is exponential. Once narrow band of radiant energy that CO2 absorbs is saturated, adding more CO2 won't do anything. To get the same increase in temperature we've already had from increasing amounts of CO2 in the atmosphere, we need to add 13 times more than we have now.

Botnst · #11 04-25-2007, 09:29 AM

Quote:

Originally Posted by mplafleur

The effect is exponential. Once narrow band of radiant energy that CO2 absorbs is saturated, adding more CO2 won't do anything. To get the same increase in temperature we've already had from increasing amounts of CO2 in the atmosphere, we need to add 13 times more than we have now.

Possibly so, which would indicate some other cause for global warming. That goes to the recently published findings by that israeli physicist who claimed that current GCC models do not adequately address solar input.

However, it doesn't predict what would (will?) happen if the atmospheric CO2 concentration approaches the Paleozoic in a geologic eye-blink. The oceans cannot absorb CO2 fast enough to moderate the concentration over the short-term, so the CO2 will accumulate in the atmosphere. The best-case scenario is that we'll get rampant, lush vegetation growth world-wide. This would accelerate reforestation world-wide. A good thing, especially considering that we have been harvesting at unsustainable rates for several generations.

One possible downside is that surface algal concentrations in all water bodies could increase substantially. So what? Surface algae block light going deeper. Remember that plants, like animals, respire day and night. Take in O2 and evolve CO2 just like us. During the day they also photosynthesize, reducing CO2 & H2O to glucose and O2. That's a good thing, of course, except sometimes the algae become so concentrated that at night the algae deplete the water of oxygen and the algae die. Decomposers start to work on the dead algae, removing even more [O2] such that only bacteria that live without O2 are able to survive. They produce things like reduced Fe, Mn, Mo, Cu, all of which become poisonous in their reduced state. Also hydrogen sulfide which not only stinks to high heaven but is itself quite poisonous to all life. This is how a water body proceeds from aerobic to anaerobic. It kills all oxygen-dependent life and leaves only oxygen-independent life.

This may have been the cause of one or more of Earth's mass extinctions in the pre-Cambrian/Cambrian/Early Paleozoic. Global warming may not be the worst outcome.

t walgamuth · #12 04-25-2007, 06:54 PM

is that the theory that i read of in which most water became so acid that we had a huge die off? it was a theory of a result of an impact from an extraterrestrial body.

like the gulf of mexico or the georgian bay.

tom w

Botnst · #13 04-25-2007, 07:15 PM

Quote:

Originally Posted by t walgamuth

is that the theory that i read of in which most water became so acid that we had a huge die off? it was a theory of a result of an impact from an extraterrestrial body.

like the gulf of mexico or the georgian bay.

tom w

I think that's one of the theories that adequately explains the sudden die-off in the Cretaceous-Tertiary boundary, right? I'm not sure if I have it exactly right but if it's important, I'll do the search and find out.