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Fossil Forest Freak Show!

‘A Dr. Seuss world’

“In the clammy depths of a southern Illinois coal mine lies the largest fossil forest ever discovered, at least 50 times as extensive as the previous contender,” the New York Times reported in its Science section this week.
“Scientists are exploring dripping passages by the light of headlamps, mapping out an ecosystem from 307 million years ago, just before the world’s first great forests were wiped out by global warming. This vast prehistoric landscape may shed new light on climate change today.”
Yada, yada, yada. But what a freak show this – fossil forest – is!


“Pushed downward over the ages by the crushing weight of rock layers higher up, the Springfield forest lies at varying depths, 250 to 800 feet underground. The researchers have only sampled it so far, in the vicinity of Galatia, Illinois, but they think it extends more than 100 miles in one direction; its width has not been ascertained.”
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“It was a Dr. Seuss world,” [Kirk Johnson, a paleobotanist at the Denver Museum of Nature and Science] said of the scale-tree forests: sun-washed quagmires studded with giant green stalks like asparagus spears, hundreds of feet tall. (Scale trees did not unfurl spreading crowns until the very end of their life cycle.) [Dr. William DiMichele of the Smithsonian National Museum of Natural History] has followed a fallen scale tree for 100 feet, before it disappeared behind coal not yet mined away. Six feet wide at the base, it was hardly any narrower at that great height.
“Scale trees had reptilian-looking, photosynthetic bark that coal miners sometimes mistake for dinosaur remains. Tube-shaped with spongy pulp inside, the trees snapped in two when storms ravaged the swamp. Immense, cylindrical roots kept stumps firmly upright, as seen in the mines.”
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“There were no birds in the Pennsylvanian period, so insects flourished in the oxygen-rich air. Hiking through the Springfield forest would have meant dodging millipedes six feet long and dragonflies the size of crows.”
Holy freakin’ cow!
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The Times article isn’t clear but the discovery actually dates back to at least 2005. From the Smithsonian:
“Smithsonian paleontologist Bill DiMichele and colleagues Howard Falcon-Lang (University of Bristol), John Nelson and Scott Elrick (Illinois State Geological Survey), and Phil Ames (Peabody Coal Company) discovered the remains of one of the world’s oldest tropical rainforests, preserved in the ceiling of a coal mine 250 feet below the surface. Their discovery was recently published in the journal Geology entitled ‘Ecological Gradients Within a Pennsylvanian Mire Forest.’
“The rainforest extends over more than four square miles as the roof of two adjacent underground coal mines in eastern Illinois. This may be the largest single-time-period fossil forest found in the fossil record.”
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That journal article was published in 2006.
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From the Illinois State Geological Survey (with photos!):
“The location of this fossil forest is just to the south and west of Danville, Illinois, about 30 miles to the east of the ISGS in Champaign, Illinois (see picture to the right). This 300 million year old fossil forest was found directly on top of the Herrin coal seam in the Riola and Vermillion Grove coal mines, and represents the last stages of the peat mire forest responsible for forming the Herrin coal.”
How was it discovered?
“One of the responsibilities of the ISGS is to try to understand the geology of the state of Illinois. For the Coal Section at the ISGS, that means trying to visit the coal mines in the state on a regular basis. When the Riola mine opened in 1996, geologists from the ISGS visited and noted the presence of fossil plants in the roof of the mine. Plant fossils are not uncommon in Illinois coal mines, so while notes were made, nothing exceptional was thought of the discovery. As time went on, more coal was mined, more of the mine roof was uncovered and the plant fossils didn’t stop! Fossils were numerous and showed excellent preservation.
“Adding visits to the Vermillion Grove mine, Survey geologists soon realized that a very interesting story was waiting to be told about the fossil plants, and in 2004, contacted Bill DiMichele from the Smithsonian and Howard Falcon-Lang of the University of Bristol, both experts in paleobotany. With the assistance of Phil Ames of Peabody Energy, a large study was then undertaken to try to understand the mosaic of preserved plant fossils presented just over our heads in the gray shale of the mine roof.”

Comments welcome.

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Posted on May 3, 2012