The World's Largest Fossil Wilderness

[Adsos Letter]

SOURCE: Smithsonian.com
By Guy Gugliotta
Photographs by Layne Kennedy

Finding a fossil in a coal mine is no big deal. Coal deposits, after all, are petrified peat swamps, and peat is made from decaying plants, which leave their imprints in mud and clay as it hardens into shale stone.

But it was a different thing entirely when John Nelson and Scott Elrick, geologists with the Illinois State Geological Survey, examined the Riola and Vermilion Grove coal mines in eastern Illinois. Etched into ceilings of the mine shafts is the largest intact fossil forest ever seen—at least four square miles of tropical wilderness preserved 307 million years ago. That's when an earthquake suddenly lowered the swamp 15 to 30 feet and mud and sand rushed in, covering everything with sediment and killing trees and other plants. "It must have happened in a matter of weeks," says Elrick. "What we see here is the death of a peat swamp, a moment in geologic time frozen by an accident of nature."

To see this little-known wonder, I joined Nelson and Elrick at the Vermilion Grove site, a working mine operated by St. Louis-based Peabody Energy and closed to the public. I donned a hard hat, a light, gloves and steel-toed boots. I received an oxygen bottle and a safety lecture. In case of emergency—poison gas, fire or an explosion—follow the red lights to find the way out of the mine, safety manager Mike Middlemas counseled. We could encounter "thick black smoke, and you won't be able to see anything in front of you." He said to use the lifeline running along the ceiling, a slender rope threaded through wooden cones, like floats in a swimming pool.

The fossil-rich coal seam is 230 feet below ground, and we rode there in an open-sided, Humvee-like diesel jitney known as a "man-trip." The driver took us through four miles of bewildering twists and turns in tunnels illuminated only by escape beacons and the vehicle's headlights. The journey took 30 minutes and ended in Area 5. The tunnels here are 6.5 feet high and about the width of a two-way suburban street.

The tunnels were silent and, lit by low-wattage bulbs, gloomy. Humid sum­mer air, drawn in from above, was chilly and clingy underground, where temperatures hover around 60 degrees Fahrenheit year-round. Miners are finished extracting coal here, and the sides of the tunnel have been sprayed with quicklime to suppress explosive coal dust. The shale roof—made of the sediment that destroyed the forest so long ago—is cracking and flaking off now that the coal below it has been removed. Wire mesh covers the ceiling to prevent big pieces from falling into the roadways or hitting miners.

http://www.smithsonianmag.com/history-archaeology/Phenomena-Forest-Primeval.html

Alink to lots of photos from this site at the right side of the article

[Tanuki]

1. This is probably the closest I will ever come to catching a glimpse of a 307 million year old

fern forest! Thanks for posting this. I used to collect fossils when I was a kid, but the ones I found were shells fossilized in limestone.

[ccharles000]

2. very interesting

[dipsydoodle]

3. Amazing

Just amazing.

[Solly Mack]

4. Thanks!

K&R

[Bravo Zulu]

5. My Dad was a Coal Miner,

sometimes he would bring me a piece of coal home with a tree leaf imprinted on it!

[Thothmes]

6. As was my grandfather

he died in an Illinois coal mine in 1943. He had severl fern fossils from the mines.

[dgibby]

7. Fascinating.

Speaking of fossils, are you familiar with "Fairy Stones" (staurite "crosses")? Here's a link:

http://www.tellmewhereonearth.com/Web%20Pages/Fairy%20Stone%20Crosses/Fairy_Stone_Crosses.htm

I have one of the crosses from Fairy Stone State Park in Va. If you haven't been there, it's definitely an interesting place to visit.

[glitch]

8. Holey moley! Thanks for posting K & R nt

[theHandpuppet]

9. Wow -- thanks so much for posting this.

Certainly puts a lot of perspective to the grand scheme of things.

[troubledamerican]

10. Got a feeling Siberia & Antarctica will challenge "biggest fossil wilderness" claims as

permafrost melts.

[and-justice-for-all]

11. I can not imagine what is under all that...

the tales they will tell someday.

[B Calm]

12. My grandfather worked these mines in Eastern Illinois from 1911

to the 1950's.

[Mari333]

13. heres a tip

go to Braidwood Ill..go to the childrens park (theres only one)...all over the park are rocks and stones...pick some up and break them...the park was built over what used to be an old mine. there are fossils galore. I found tons of stuff,,,went with a geologist friend..years ago...
lots of places are loaded with fossils. specially old sites where mining was done.