I'm Scott Elrick from the Illinois State Geological Survey, one of the researchers involved in the original discovery. Here's a little background:
* This current story is an extension of a story from a year ago. When the story broke, I popped onto Slashdot to answer questions - http://slashdot.org/comments.pl?sid=232903&cid=18936603 (ignore the misspellings in those posts!)
* As a result of the publicity, I used some of the guts of my postings above to put together this webpage: http://www.isgs.uiuc.edu/research/coal/fossil-forest/fossil-forest.shtml I tried to make a 'general public' kind of site that covers most of the basics and posted all of the pictures we took.
* There should be an article coming out in Smithsonian magazine about the discovery in a few months time.
Now to the current news.
Our colleague Dr. Howard Falcon-Lang of the University of Bristol, UK is heading up a multi year research effort to examine the Desmoinesian - Missourian boundary in the Middle Penn. Howard, Bill DiMichele of the Smithsonian Institute, John Nelson and myself of the ISGS, Isabel Montañez of UC Davis and Neil Tabor of SMU will all be collaborating to work out the paleobotanical, sedimentologic, CO2, and climate history of this large scale climate transition. Really this is more an announcement of further research than of results!
As flat as Illinois is, we do have a pretty good record of this transitional period Rocks in Illinois? Who knew!
Cheers!
p.s. I covered a fair amount of ground in my previous postings last year in terms of answering questions. I'll pop back later this evening and see if any more pop up though.
In a funny way, the 'march of industry' will end up both providing the chance to see and study... and eventually (when the mine closes) close it as well.
I would say that plant fossils in general are relatively common in association with coal seams and by extension with coal mines in Illinois. More so mines with non-marine sediment rock covering the coal. (like the gray shale of these mines). Outside of coal seams the rarity increases quite a bit. Often times concretions found in a variety of localities will reveal fossil plants. (Mazon creek in Illinois for example).
To answer by way of your analogy? I would say buried school lab of Apple ]['s... found in Cupertino, CA! In otherwords, common in the places where you would expect to find them.
Actually, most of my replies as well as my initial posting have been from home! So minimal tax dollar waste I assure you!:)
Phew... Well, I can't even begin to speculate on larger questions such as the ones you've posted, and honestly can only speak from my own experiences. But as I mentioned before, Peabody has been very accomodating to us and we do appreciate it!
Yeah, the fifteen minutes will probably run out any moment now!
Peabody Energy (owners of the coal mines) was extremely accommodating of our work in the mine. As they mined the coal, they exposed more and more roof shale for us to examine... and yes they kept on mining. We were able to easily go around their operations and stay out of their way.
I'm afraid you are correct in that it is something you look at, record and describe to the best of your ability and then take out the best samples you can. That's one of the reasons we try to visit the mines on a regular basis. To see what's going on geologically! Fortunately, you can go see a bit of this fossil forest today at the museum of science and industry in Chicago. When they remodeled their coal mining exhibit a few years ago (6 or 7 I think) Riola mine donated a big slab of shale containing plant fossils for display.
We did find a few pieces of a Eurypterid, a fossil 'sea-scorpian' but this was a plant dominated fossil assemblage and thats where we spent the majority of our time!
Good question about the state of the fossils. As you will be able to see from the pictures we post on Friday, most of the plants show up as carbonized impressions on the shale. Some of the plant material actually transforms all the way to coal if it was thick enough to begin with.
A coal mine looks a lot like an extremely dusty low-ceiling network of orthogonally intersecting hallways.
The walls, floor and ceiling are covered in whitish gray limestone dust... sprayed on just after the mining process in order to protect against explosions propagating in the mine. (the basic idea is that if there is an explosion in the mine, from excess methane for example, the limestone dust gets kicked up into the onrushing air mass, snuffing out the combustion.)
Areas that have been exposed for some time often will show signs of roof sloughing. Yearly summer humidity in the air swells clays in the roof shale, making them expand and winter dry air makes the clay contract (dries the clay out). Over time the 'pulsating' roof shale spalls off the ceiling and exposes big gray swaths of roof shale which in this mine also contained many black carbonized plant fossils.
There are two answers to your query. The first details what we do for our sampling study (i.e. population counts, etc..). The second details the physical sampling process (which is painfully obvious once you read it...).
The first step in any population sampling of course is getting the lay of the land first. I.e. what areas are available for the study. Because of the huge distances to cover in our study, we would go to an area in the mine, scout around and see what the make up of the forest was and then try to find a representative locality to sample. Sampling then consisted of 'quartering' the locality and proceeding to rate each identified species as 'rare', 'common', etc.. within each quarter. (Counting actual numbers would be an exercise in futility as the numbers are just too great)
The physical collection process was based on what we observed in the population sampling. We wanted to collect physical specimens that reflected the general plant distributions of each locality. So for example, if there were alot of seed ferns and very few reeds we looked for a physical specimen that showed just that. The collection itself?
Heh heh, like every other geologist in the world looking for samples! Find the stuff that is already loose and free! Basically we looked in the fallen roof material until we found a slab that contained just the right balance of species to reflect what we observed. That could mean taking two or three smaller chunks to get the right balance.
The fun question? Do I get to date Julianne Moore? Sign me up! (sorry honey, I don't mean it... really!)
I guess my overall feeling can be summed up by a Winston Churchill quote:
"A fanatic is one who can't change his mind and won't change the subject"
I agree that ignorance of science is a problem... especially as it impacts policy decisions and the future of my baby daughter (it only really hits, when it hits home). Will things need to get worse before they get better? Does the U.S. need to lose its (arguable) science and technology leadership role in the world before changes occur. I.e. do we need another Sputnik to give us a kick in the pants? The answer may be yes. I do however, believe that things like this can change rather quickly given the proper motivation. The motivation? Either get with the times or get eaten. (as a relevant culture) It is my fervent hope that our society, that prides itself on 'We're number 1!' will do what is necessary to get back there.
The question becomes then, what do I (you) do about this? Personally, I think the most effective use my time is not spent trying to convince the unconvinceable. Instead I prefer to educate and motivate, try to get those brains wondering and thinking. The effort in letting lose an active questioning mind is worth way more than banging your head against that particular brick wall.
I admit to this being the first time I have heard of this idea so forgive me if I don't have a reasoned answer for you. (knowing ones ignorance is a good thing!)
I think some of the complicating factors in testing out this concept would be that there are major oil and coal deposits in the world of Jurassic (180 million to 140 million years ago) and Cretaceous (140 million to 65 million years ago) age, well after the arrival of heterotrophs.
Now it could be that the volume of oil and coal is less for these more recent time periods in comparison to the pre-heterotroph time, but I don't have any direct knowledge about this and you should consider the above speculation only!
I also wonder how the geographic arrangement of the continents over time has affected the productivity of these biologic dumping grounds. For example, the Pennsylvanian time period has just the right combination of climate, geographic distribution of land, sea and species to turn the then equatorial belts of central North America and Western Europe into veritable vegetation producing power houses. I would speculate that a different geographic setting.. say alot more ocean at the equator and less land could have produced a different biologic concentration.
I hasten to add though that this is the first I have thought about this and I'm figuratively spinning my wheels!
Yes, not much in print on the Royal Center fault on the web that I could find. I know we have some publications that reference it but I can't recall the pub titles off hand. (need to look back at my compiled notes)
As to deformation features, the Illinois Basin has certainly seen the 'far-field' effects of continental collisions but it is really pretty well protected in the center of the North American plate and has mainly seen deformation along reactivated basement faults. Every time something big was happening out east or west on a continental scale those basement faults would jostle and shift a bit, sliding up or down bending the rocks above the faults into gentle folds... or sometimes breaking and faulting to the surface. Pretty tame though when compared to California! For this area, the dominant structural feature (aside from the down-dropped fault block) is the Illinois Basin itself. A large, slowly subsiding cratonic depression that has been a locus of deposition since at least the very latest pre-cambrian, 600+ million years ago.
I'm sure animal remains were there to be found... but we missed them, only seeing the Eurypterid pieces. The fossil plants certainly dominated the setting and the bulk of our efforts were in fleshing that part of the story out.
By the way, I would very much like to visit Iceland! What a beautiful combination of fire and ice!
The ISGS is not a regulatory agency in any way. We are a scientific branch of state government and charged with understanding (to the best of our ability) the geology of the state. So we are not really in a position to make demands!
Having said that, I have nothing but positive things to say about Peabody Energy and their accomodation of our desires and wants. If we needed to get into just about any part of the mine that was still open (baring safety issues of course) they found a way to get us there.
When we show up for visits, we cost the company the man work hours of the miner showing us around as well as his salary cost and the cost of transportation in the mine. I know for certain that our mere presence was disruptive to their operations and yet they went out of their way to help us out. Like I said, nothing but praise from us! In fact, they even shared drill hole information with us to help figure out the rock layer thicknesses that was vital to our landscape reconstructions.
We actually want them to mine as much coal as possible. Why? Because every mined passageway is a new exposure of roof rock for us to look for fossils. And the company, for their own economic reasons, wants to leave as much of that fossil bearing shale behind as it is junk rock to them for the purpose of selling coal! A nice symbiotic relationship!
The logistics aspect is kind of interesting too. Coal mines are dusty somewhat confusing places to work. You have only the light on your cap lamp to see with, you need to keep your location pinpointed on the mine map (no GPS in the mines! Though in-mine navigation is coming to a few mines), keep an eye out for fossils... keeping track of what you are seeing and how it fits into the bigger picture is a physical and mental challenge.
Anyone who has been out mapping geology or working in a field that requires concurrent mental and physical activity, knows that sometimes you can work for hours in a particular spot and only after seeing large areas can you start to build a framework in your head of whats going on. In fact, one of the most important lessons on this was taught to me by my co-worker John Nelson at the ISGS. When John encounters some interesting geology in a mine, the first thing he does is NOT examine the feature, but to look all around the feature, up adjacent passageways and everywhere else but at the actual feature. Only after he has seen the surrounding geology, i.e. the context of the thing in question does he start to examine the feature in question. It really helps hone your thinking in on what the possibilities may be.
Sorry, digressed there. In this investigation a big issue was the really large area we needed to cover. We're talking about a lot of feet of passageways to walk down, looking for good sampling locations. So we had to make 'intelligent haste' (sounds like a cool new spell for AD&D), picking our target areas carefully in order to get maximum sampling coverage as well as the flexibility to target in on specific areas for more concentrated study on resolving geologic issues.
All this while keeping an eye out any possible dangerous conditions (loose rocks overhead, bad roof conditions, mud holes in the floor). Is it any wonder the mine sends an employee to look after us? A mine is not a place for the absent minded professor!
As a geology professor of mine once said: "You can lead a horse to water, but can't make him think!"
My professor was unfortunately describing we students and our inability to 'see' the geologic story that was laid out like a cold lunch in front of us, but it does make a good turn of phrase!
The Royal Center fault, our candidate fault for the earthquake, is a deep crustal fault that is probably similar in character, though NOT in size or 'genetic affinity' to the huge crustal faults responsible for the present day Rocky Mountains. The examples you list in your post are indeed subduction zone related tectonics and the plate shifting up or down is a result of that close proximity.
The Royal Center would have been an intra-plate earthquake perhaps in a fashion similar to the New Madrid earthquakes of recent historical fame. (google New Madrid earthquake for a pleathora of interesting links!) As to the scale of our proposed earthquake, I'll readily admit to not knowing enough to intelligently speculate on exact magnitude, but to drop an area like this multiple feet at once, it probably wasn't small!
An excellent website on paleogeographic reconstructions and continental plates through time is Dr. Ron Blakey's (of Northern Arizona University) page here:
Notice that this reconstruction shows all of Illinois to be covered by water. This is well supported in the geologic record here in Illinois. A repeating pattern of sea-level rise and fall, (we think caused by global glaciation taking up water to ice form and then melting away) has lead to the also repeated cycle of sea level fall, exposure of the land surface, colonization by land plants, then rise of sea level and covering with sediment. Repeat again and again. The geologic record shows this as a repeating rock pattern called a 'cyclothem'. Cyclothems being viewed throughout much of the Pennsylvanian period and much of the midcontinent of the U.S. (the Mississippian has a glacial overprint as well, though few coal measures)
In short, I just wanted to point out that showing a sea covering Illinois at 300 million years ago is not a mistake, the 300 million year time indicator in Dr. Blakey's image is a generalized one and shouldn't be taken to mean an absolute rigid date.
Thanks for the link to your earthquake page! I'll be sure to check it out!
To be honest, I really have not had much of that at all. Now, granted I live in a university town (UIUC) and am probably pretty insulated, but even heading out to various towns around the state for field work or otherwise I just really don't get much!
Of course, my sample is my state... Illinois, which probably swings in the middle or a little blue.
Thats not what you are asking though. You would like to know what I say to people who would prefer to believe the earth to be 6000 years old.
Now, I have not said this to any person in particular, but one thing that comes to mind that I find a bit humorous. Coal seams are sometimes considered by the '6000' groups to be the remnants of the great flood. The idea being that a great peat swamp from an indeterminate area was torn asunder during the great flood and then covered by sediments settling out from the great flood. The evidence then being the thick sediments found on top of the coal.
In the Illinois Basin there are 7 major coal seams (each covering a good percentage of Illinois in map view) and a total of about 80 minor coal seams all stacked (roughly speaking) vertically on top of each other with 'thick' sediment on top of each seam... So are we to infer that God was practicing his flooding technique?!? Eighty times??
Sorry, maybe it's just my sense of humor, but I think it's woth a chuckle.
Seriously, it seems to me that the core of the issue here is one of belief and personal belief, not of science or investigative logic. It is entirely possible to layout all the necessary proof and interconnected evidence in as grand a scheme as you desire towards proving a thing, but in the end when this discussion is broached you are no longer talking about ideas. A comment that is made against a belief is inevitably a vicous strike against the very essense of the person. In effect a personal attack... no mater what you say!
My real answer is not a satisfying one I'm afraid. In truth I prefer not to engage anyone who wants to combatively challenge me in 'belief match' contest. I certainly respect others beliefs, no matter how incorrect I think them to be, and hope they would respect mine, but in the end it is not a battle to be won. The battle, to the extent it is a battle anyway, is in education and getting people to ask questions, wonder why, wonder how, wonder who, and what.
If you check out the response to 'Puff of Logic' just above, I sort of touch on what we learned in the study. Essentially that the complexities and subtles of the ancient 300 million year old Pennsylvanian age peat mire forests are at a similar level as the forests of today.
The question of species evolution was not really the focus of this study, but I can say that some of the plants alive then such as the seed ferns have no modern day equivalent, whereas the long, crazy-tall reed-like plants called calamites have modern day equivalents (or closest relatives anyway) in horsetails. (a fairly common plant in water filled ditches).
DNA analysis is probably not possible, however, I am certainly not an expert in that area. A lot of the organic material has been cooked and in the case of the peat, cooked and compressed to form... (you guessed it!) Coal. So that is probably a dead end I'm afraid.
No new species were found, but we did have some head scratcher "What the heck is that?" "I don't know" "Get a sample, we'll see what we can figure out later" kind of stuff! And no, I don't think we have identified everything yet...
When I was making my nightly visit to Slashdot... (no I shant admit the ACTUAL number of times I visit!) I saw the headline, sighed and thought, "Okay bucko, time to earn your keep!"
It's actually been a lot of fun to share our excitement!
It's a pleasure to be posting. I have been a super-ultra-long-time-gets-the-funny-all-your-base -jokes lurker for just about forever.
Part one of your question is asking if the catastrophic event of earthquake induced flooding be destructive to forest-floor plants. A very good question.
To answer that I'll steal some text that will be going on the website this Friday as written by Bill DiMichele to describe the ground cover plants and follow up afterward:
"Ground cover plants:
Plants inferred from their growth forms to have been ground cover are not common at Riola. This suggests that the soil surface may have been inhospitable to the growth of small plants, perhaps due to flooding.
One plant in particular, Sphenophyllum, was widespread throughout the mine but rare. Sphenophyllum (Images 51 & 52) is a sphenopsid, the same higher-level group that includes the horsetails. Like that group of plants, it has "node-internode" construction and its leaves and branches are borne in whorls. In this instance, however, the leaves are wedge-shaped, a distinctive attribute of these plants. Some Sphenophyllum species have hooks or barbs on their leaves, suggesting that they too formed thickets or tangles, and perhaps may have climbed other trees for support.
Another potential ground cover plant, a possible small fern or seed plant, is Sphenopteris (Image 53), which is rare in the Riola mine. Sphenopteris is characterized by small fronds that have small, variously lobed pinnules."
One reason to believe that the flooding, while catastrophic in the sense that it was sudden, may not have been particularly violent is the lack of strong linear orientation of both plants and logs, nor any preferred 'piling' of leaf litter and debris up against upright tree stumps. I personally would imagine the flooding of the forest to be in the multiple minutes category and not the 'large imposing' violent wave category. As Bill writes above, the ground surface may not have been conducive to thick luxuriant cover, but I also wonder to what degree the Sphenophyllum 'hooks and barbs' may have rooted them in place under flooding duress!
The second part of your question asks about the importance of smaller life being critical to an understanding of forest ecology.
You got that right! In modern forests the importance of 'smaller life' is undeniable.
In geology we are often forced by lack of data to fill in the gaps as best as we are able to infer. Or we are required to 'complete the puzzle' with the available puzzle pieces. Along those lines, much of the picture of these 300 million year old peat mires comes about through many many many individual finds and discoveries. A few insects here... an amphibian there... ground cover plants here... massive monster of tree there... a complete coal ball collection detailing plant diversities and general ecologies here... glimpses of many of these individuals (but not all unless you've got good karma) together in one spot there... etc.. Put all the individual puzzle pieces together and a cohesive picture starts to form.
For this particular study I feel pretty confident in saying that we are almost certainly missing big chunks of 'the little stuff'. For example, we may have seen some insect parts, but we can't be sure. Did they get swept away? Fly away? Hard to know. We are absolutely missing the entire ecological picture here and in that sense the answer to your question is a disappointing, "Nope, we don't have it all, so we don't have the honest to gosh whole picture"
But what this study does provide is some confirmation that the picture we have theorized about... i.e. we think the Pennsylvanian peat mire ecology looks like 'X' is correct. That the subtle variations in forest ecology that you would see walking down a hiking trail in your nearby state park ("Hmm, first I saw maples, and 300 feet later I saw a few oaks, and then the maples thinned out and the oaks were dominant"
Assassin bug asked nearly the same thing. We did find Eurypterid (http://en.wikipedia.org/wiki/Sea_scorpion) pieces mixed in with the plant fossils and there is the possibility of some insect parts (legs, etc..) in some of the 'hashier' areas of the roof.
But, as I mentioned to Assassin bug, we had a LOT of territory to cover in fairly short amount of time, so we had to concentrate on the dominant plant fossils.
Your speculation on the moveable critters in the system 'getting the heck out of dodge' when the ground dropped out from underneath them may well be true. I would hope that at least some died and stayed put! Time (to collect data) was our enemy here.
I should probably have mentioned this before, but we are very thankful that Peabody Energy allowed us into the mine to study and record this wonderful fossil forest. It costs them man power and time to shepard us in their mines and they have been very supportive of our efforts. Truthfully, without them extracting the coal in the first place, we would never have been able to see the steady unveiling (10 years time!) of this 300 million year old snapshot in time.
Howard Falcon-Lang and Bill Dimichele did find Eurypterid parts and pieces for certain and in some 'hashy' areas we may have found insect parts but it was hard to tell. Truthfully, the study area was so dang large that we were forced to really 'make tracks' to cover what we could, I am certain short-changing areas of interest such as your own in favor of the dominant plant fossils. I think I described the task to one reporter as trying to make a map of all the store fronts in New York city in a few days of walking the city, ending up with your 'chinatown area' ' little italy area' etc..
A shame now in retrospect that we didn't make more of an effort to look for those other parts of the system... but oh baby did we have a lot of ground to cover!
We do have representative samples from the mine roof that are currently in the Smithsonian collection, and hopefully Grimalidi can snag some time to give them a look over.
One of the authors here (Scott Elrick - geologist from the Illinois State Geological Survey). I would be happy to answer questions from folks... or at least try!
I can start by giving a basic overview of the discovery, what we found, and how it is important (to paleobotanists that is).
The location of the fossils is just to the south and west of Danville, IL, itself about 30 miles to the east of the University of Illinois, Urbana-Champaign (say hi to HAL when you come to visit). The forest was found directly above the Herrin coal seam in the Riola and Vermillion Grove coal mines, owned by Black Beauty coal (a subsidiary of Peabody Energy). The mines cover approximately 15 square miles and the study area was about 4 square miles... actually 1000 hectares. (I'm rounding up the square miles)
Okay, so what's so cool? If you are a geologist and read the headlines that have been popping up about the story, you may have scoffed and shook your head saying, "What do they mean largest fossil forest? A coal seam is nothing but the fossil remnants of a fossil forest. And a coal seam like the Colchester coal extended from Pennsylvania all the way to Oklahoma!" And you are correct! (This is my first exposure to the modern day media... and its been an eye opener! Give them credit, they do a pretty god job overall)
What is 'largest' about this fossil forest story is that it is the largest STUDY of a mostly entact fossil forest. Specifically one that is looking at the ecology of that forest. The largest study before this that looked at the overall ecology was about 25 hectares.. say about 1/10th of a square mile. So this study is an order of magnitude greater. The meat of the matter here is that we had an opportunity to examine a fossil forest at just a wonderfully huge scale and as a result were able to see subtle changes in the make-up of the forest as we walked the multiple miles of passageways in the mine.
The analogy is that previous studies were like blindfolded people examining an elephant. Each person has a wonderfully detailed and accurate description of his or her patch of the elephant, and when they compare notes a decent group consensus exists as to what the elephant probably looks like... but nobody has a chance to see the whole elephant. Our study is where we get to step back from the elephant a bit and take a pretty good peak under the blindfold at the whole animal. (I wont go so far as to say we are able to clearly see the whole thing as that is stretching the analogy. The point being it is an important and exciting step forward, but not necessarily a monstrous revelation!)
A couple of things to highlight.
First, the part that I find the coolest about work like this. In much of geologic science (field aspects more so), geologists look at vast spreads of time in small geographic slices. For example, standing at the rim of the Grand Canyon and peering across to the other side, your eye takes in millions of years of geologic time... but you are only able to see a thin 'slice' of each unit in profile. What does a particular rock unit look like 500 feet into the side of the canyon walls? The only way to find out is to drill a hole and take a core sample.
Geologic research, or in this case paleontological research, in an underground mine such as these coal mines is orthogonal to the norm above! At these mines, looking up at preserved trees and ferns in the mine ceiling, we were looking at single slice of time, a T(0) event, over a huge (relatively speaking) geographic area. That means that we were able to get a snapshot in time look at the forrest landscape of 300 million years ago. It's the 'worms eye' view of a fossil forest.
I should point out that the 'discovery' of this fossil forest was a gradual process. One of the responsibilities of the Illinois State Geological Survey is to try to understand the geology of the state of Illinois... and for us in the coal section that means coworker John Nelson and I (also one of the aut
Slashdot Mirror
Greetings folks,
I'm Scott Elrick from the Illinois State Geological Survey, one of the researchers involved in the original discovery. Here's a little background:
* This current story is an extension of a story from a year ago. When the story broke, I popped onto Slashdot to answer questions - http://slashdot.org/comments.pl?sid=232903&cid=18936603 (ignore the misspellings in those posts!)
* As a result of the publicity, I used some of the guts of my postings above to put together this webpage: http://www.isgs.uiuc.edu/research/coal/fossil-forest/fossil-forest.shtml I tried to make a 'general public' kind of site that covers most of the basics and posted all of the pictures we took.
* From the guts of the webpage, I put together a magazine article for 'Outdoor Illinois' on the discovery. Here's a PDF (direct link) of the article - http://www.isgs.uiuc.edu/research/coal/fossil-forest/Outdoor-IL-art.pdf
* By the end of the year we made it into the top 100 stories of 2007 in Discover magazine - http://discovermagazine.com/2008/jan/fossils-of-a-300-million-year-old-forest-found
* There should be an article coming out in Smithsonian magazine about the discovery in a few months time.
Now to the current news.
Our colleague Dr. Howard Falcon-Lang of the University of Bristol, UK is heading up a multi year research effort to examine the Desmoinesian - Missourian boundary in the Middle Penn. Howard, Bill DiMichele of the Smithsonian Institute, John Nelson and myself of the ISGS, Isabel Montañez of UC Davis and Neil Tabor of SMU will all be collaborating to work out the paleobotanical, sedimentologic, CO2, and climate history of this large scale climate transition. Really this is more an announcement of further research than of results!
As flat as Illinois is, we do have a pretty good record of this transitional period Rocks in Illinois? Who knew!
Cheers!
p.s. I covered a fair amount of ground in my previous postings last year in terms of answering questions. I'll pop back later this evening and see if any more pop up though.
In a funny way, the 'march of industry' will end up both providing the chance to see and study... and eventually (when the mine closes) close it as well.
I would say that plant fossils in general are relatively common in association with coal seams and by extension with coal mines in Illinois. More so mines with non-marine sediment rock covering the coal. (like the gray shale of these mines). Outside of coal seams the rarity increases quite a bit. Often times concretions found in a variety of localities will reveal fossil plants. (Mazon creek in Illinois for example).
To answer by way of your analogy? I would say buried school lab of Apple ]['s... found in Cupertino, CA! In otherwords, common in the places where you would expect to find them.
Hows that?
Actually, most of my replies as well as my initial posting have been from home! So minimal tax dollar waste I assure you! :)
Phew... Well, I can't even begin to speculate on larger questions such as the ones you've posted, and honestly can only speak from my own experiences. But as I mentioned before, Peabody has been very accomodating to us and we do appreciate it!
Yeah, the fifteen minutes will probably run out any moment now!
Peabody Energy (owners of the coal mines) was extremely accommodating of our work in the mine. As they mined the coal, they exposed more and more roof shale for us to examine... and yes they kept on mining. We were able to easily go around their operations and stay out of their way.
I'm afraid you are correct in that it is something you look at, record and describe to the best of your ability and then take out the best samples you can. That's one of the reasons we try to visit the mines on a regular basis. To see what's going on geologically! Fortunately, you can go see a bit of this fossil forest today at the museum of science and industry in Chicago. When they remodeled their coal mining exhibit a few years ago (6 or 7 I think) Riola mine donated a big slab of shale containing plant fossils for display.
We did find a few pieces of a Eurypterid, a fossil 'sea-scorpian' but this was a plant dominated fossil assemblage and thats where we spent the majority of our time!
Good question about the state of the fossils. As you will be able to see from the pictures we post on Friday, most of the plants show up as carbonized impressions on the shale. Some of the plant material actually transforms all the way to coal if it was thick enough to begin with.
A coal mine looks a lot like an extremely dusty low-ceiling network of orthogonally intersecting hallways.
The walls, floor and ceiling are covered in whitish gray limestone dust... sprayed on just after the mining process in order to protect against explosions propagating in the mine. (the basic idea is that if there is an explosion in the mine, from excess methane for example, the limestone dust gets kicked up into the onrushing air mass, snuffing out the combustion.)
Areas that have been exposed for some time often will show signs of roof sloughing. Yearly summer humidity in the air swells clays in the roof shale, making them expand and winter dry air makes the clay contract (dries the clay out). Over time the 'pulsating' roof shale spalls off the ceiling and exposes big gray swaths of roof shale which in this mine also contained many black carbonized plant fossils.
Hope that helps!
Hi CGZ!
Glad to be inspirational for you!
Question about the fossil collecting process:
There are two answers to your query. The first details what we do for our sampling study (i.e. population counts, etc..). The second details the physical sampling process (which is painfully obvious once you read it...).
The first step in any population sampling of course is getting the lay of the land first. I.e. what areas are available for the study. Because of the huge distances to cover in our study, we would go to an area in the mine, scout around and see what the make up of the forest was and then try to find a representative locality to sample. Sampling then consisted of 'quartering' the locality and proceeding to rate each identified species as 'rare', 'common', etc.. within each quarter. (Counting actual numbers would be an exercise in futility as the numbers are just too great)
The physical collection process was based on what we observed in the population sampling. We wanted to collect physical specimens that reflected the general plant distributions of each locality. So for example, if there were alot of seed ferns and very few reeds we looked for a physical specimen that showed just that. The collection itself?
Heh heh, like every other geologist in the world looking for samples! Find the stuff that is already loose and free! Basically we looked in the fallen roof material until we found a slab that contained just the right balance of species to reflect what we observed. That could mean taking two or three smaller chunks to get the right balance.
The fun question? Do I get to date Julianne Moore? Sign me up! (sorry honey, I don't mean it... really!)
I guess my overall feeling can be summed up by a Winston Churchill quote:
"A fanatic is one who can't change his mind and won't change the subject"
I agree that ignorance of science is a problem... especially as it impacts policy decisions and the future of my baby daughter (it only really hits, when it hits home). Will things need to get worse before they get better? Does the U.S. need to lose its (arguable) science and technology leadership role in the world before changes occur. I.e. do we need another Sputnik to give us a kick in the pants? The answer may be yes. I do however, believe that things like this can change rather quickly given the proper motivation. The motivation? Either get with the times or get eaten. (as a relevant culture) It is my fervent hope that our society, that prides itself on 'We're number 1!' will do what is necessary to get back there.
The question becomes then, what do I (you) do about this? Personally, I think the most effective use my time is not spent trying to convince the unconvinceable. Instead I prefer to educate and motivate, try to get those brains wondering and thinking. The effort in letting lose an active questioning mind is worth way more than banging your head against that particular brick wall.
Am I worried? Yes.
Excellent links. Thanks for adding them!
Interesting!
I admit to this being the first time I have heard of this idea so forgive me if I don't have a reasoned answer for you. (knowing ones ignorance is a good thing!)
I think some of the complicating factors in testing out this concept would be that there are major oil and coal deposits in the world of Jurassic (180 million to 140 million years ago) and Cretaceous (140 million to 65 million years ago) age, well after the arrival of heterotrophs.
Now it could be that the volume of oil and coal is less for these more recent time periods in comparison to the pre-heterotroph time, but I don't have any direct knowledge about this and you should consider the above speculation only!
I also wonder how the geographic arrangement of the continents over time has affected the productivity of these biologic dumping grounds. For example, the Pennsylvanian time period has just the right combination of climate, geographic distribution of land, sea and species to turn the then equatorial belts of central North America and Western Europe into veritable vegetation producing power houses. I would speculate that a different geographic setting.. say alot more ocean at the equator and less land could have produced a different biologic concentration.
I hasten to add though that this is the first I have thought about this and I'm figuratively spinning my wheels!
Yes, not much in print on the Royal Center fault on the web that I could find. I know we have some publications that reference it but I can't recall the pub titles off hand. (need to look back at my compiled notes)
As to deformation features, the Illinois Basin has certainly seen the 'far-field' effects of continental collisions but it is really pretty well protected in the center of the North American plate and has mainly seen deformation along reactivated basement faults. Every time something big was happening out east or west on a continental scale those basement faults would jostle and shift a bit, sliding up or down bending the rocks above the faults into gentle folds... or sometimes breaking and faulting to the surface. Pretty tame though when compared to California! For this area, the dominant structural feature (aside from the down-dropped fault block) is the Illinois Basin itself. A large, slowly subsiding cratonic depression that has been a locus of deposition since at least the very latest pre-cambrian, 600+ million years ago.
I'm sure animal remains were there to be found... but we missed them, only seeing the Eurypterid pieces. The fossil plants certainly dominated the setting and the bulk of our efforts were in fleshing that part of the story out.
By the way, I would very much like to visit Iceland! What a beautiful combination of fire and ice!
Good questions.
:)
The ISGS is not a regulatory agency in any way. We are a scientific branch of state government and charged with understanding (to the best of our ability) the geology of the state. So we are not really in a position to make demands!
Having said that, I have nothing but positive things to say about Peabody Energy and their accomodation of our desires and wants. If we needed to get into just about any part of the mine that was still open (baring safety issues of course) they found a way to get us there.
When we show up for visits, we cost the company the man work hours of the miner showing us around as well as his salary cost and the cost of transportation in the mine. I know for certain that our mere presence was disruptive to their operations and yet they went out of their way to help us out. Like I said, nothing but praise from us! In fact, they even shared drill hole information with us to help figure out the rock layer thicknesses that was vital to our landscape reconstructions.
We actually want them to mine as much coal as possible. Why? Because every mined passageway is a new exposure of roof rock for us to look for fossils. And the company, for their own economic reasons, wants to leave as much of that fossil bearing shale behind as it is junk rock to them for the purpose of selling coal! A nice symbiotic relationship!
The logistics aspect is kind of interesting too. Coal mines are dusty somewhat confusing places to work. You have only the light on your cap lamp to see with, you need to keep your location pinpointed on the mine map (no GPS in the mines! Though in-mine navigation is coming to a few mines), keep an eye out for fossils... keeping track of what you are seeing and how it fits into the bigger picture is a physical and mental challenge.
Anyone who has been out mapping geology or working in a field that requires concurrent mental and physical activity, knows that sometimes you can work for hours in a particular spot and only after seeing large areas can you start to build a framework in your head of whats going on. In fact, one of the most important lessons on this was taught to me by my co-worker John Nelson at the ISGS. When John encounters some interesting geology in a mine, the first thing he does is NOT examine the feature, but to look all around the feature, up adjacent passageways and everywhere else but at the actual feature. Only after he has seen the surrounding geology, i.e. the context of the thing in question does he start to examine the feature in question. It really helps hone your thinking in on what the possibilities may be.
Sorry, digressed there. In this investigation a big issue was the really large area we needed to cover. We're talking about a lot of feet of passageways to walk down, looking for good sampling locations. So we had to make 'intelligent haste' (sounds like a cool new spell for AD&D), picking our target areas carefully in order to get maximum sampling coverage as well as the flexibility to target in on specific areas for more concentrated study on resolving geologic issues.
All this while keeping an eye out any possible dangerous conditions (loose rocks overhead, bad roof conditions, mud holes in the floor). Is it any wonder the mine sends an employee to look after us? A mine is not a place for the absent minded professor!
In short. I loved every minute of it.
Thanks frogstar,
As a geology professor of mine once said: "You can lead a horse to water, but can't make him think!"
My professor was unfortunately describing we students and our inability to 'see' the geologic story that was laid out like a cold lunch in front of us, but it does make a good turn of phrase!
Hello jonfr,
The Royal Center fault, our candidate fault for the earthquake, is a deep crustal fault that is probably similar in character, though NOT in size or 'genetic affinity' to the huge crustal faults responsible for the present day Rocky Mountains. The examples you list in your post are indeed subduction zone related tectonics and the plate shifting up or down is a result of that close proximity.
The Royal Center would have been an intra-plate earthquake perhaps in a fashion similar to the New Madrid earthquakes of recent historical fame. (google New Madrid earthquake for a pleathora of interesting links!) As to the scale of our proposed earthquake, I'll readily admit to not knowing enough to intelligently speculate on exact magnitude, but to drop an area like this multiple feet at once, it probably wasn't small!
An excellent website on paleogeographic reconstructions and continental plates through time is Dr. Ron Blakey's (of Northern Arizona University) page here:
http://jan.ucc.nau.edu/~rcb7/nam.html
In fact, check out his reconstruction for 300 million years ago here:
http://jan.ucc.nau.edu/~rcb7/namPP300.jpg
Notice that this reconstruction shows all of Illinois to be covered by water. This is well supported in the geologic record here in Illinois. A repeating pattern of sea-level rise and fall, (we think caused by global glaciation taking up water to ice form and then melting away) has lead to the also repeated cycle of sea level fall, exposure of the land surface, colonization by land plants, then rise of sea level and covering with sediment. Repeat again and again. The geologic record shows this as a repeating rock pattern called a 'cyclothem'. Cyclothems being viewed throughout much of the Pennsylvanian period and much of the midcontinent of the U.S. (the Mississippian has a glacial overprint as well, though few coal measures)
In short, I just wanted to point out that showing a sea covering Illinois at 300 million years ago is not a mistake, the 300 million year time indicator in Dr. Blakey's image is a generalized one and shouldn't be taken to mean an absolute rigid date.
Thanks for the link to your earthquake page! I'll be sure to check it out!
To be honest, I really have not had much of that at all. Now, granted I live in a university town (UIUC) and am probably pretty insulated, but even heading out to various towns around the state for field work or otherwise I just really don't get much!
Of course, my sample is my state... Illinois, which probably swings in the middle or a little blue.
Thats not what you are asking though. You would like to know what I say to people who would prefer to believe the earth to be 6000 years old.
Now, I have not said this to any person in particular, but one thing that comes to mind that I find a bit humorous. Coal seams are sometimes considered by the '6000' groups to be the remnants of the great flood. The idea being that a great peat swamp from an indeterminate area was torn asunder during the great flood and then covered by sediments settling out from the great flood. The evidence then being the thick sediments found on top of the coal.
In the Illinois Basin there are 7 major coal seams (each covering a good percentage of Illinois in map view) and a total of about 80 minor coal seams all stacked (roughly speaking) vertically on top of each other with 'thick' sediment on top of each seam... So are we to infer that God was practicing his flooding technique?!? Eighty times??
Sorry, maybe it's just my sense of humor, but I think it's woth a chuckle.
Seriously, it seems to me that the core of the issue here is one of belief and personal belief, not of science or investigative logic. It is entirely possible to layout all the necessary proof and interconnected evidence in as grand a scheme as you desire towards proving a thing, but in the end when this discussion is broached you are no longer talking about ideas. A comment that is made against a belief is inevitably a vicous strike against the very essense of the person. In effect a personal attack... no mater what you say!
My real answer is not a satisfying one I'm afraid. In truth I prefer not to engage anyone who wants to combatively challenge me in 'belief match' contest. I certainly respect others beliefs, no matter how incorrect I think them to be, and hope they would respect mine, but in the end it is not a battle to be won. The battle, to the extent it is a battle anyway, is in education and getting people to ask questions, wonder why, wonder how, wonder who, and what.
Hello!
If you check out the response to 'Puff of Logic' just above, I sort of touch on what we learned in the study. Essentially that the complexities and subtles of the ancient 300 million year old Pennsylvanian age peat mire forests are at a similar level as the forests of today.
The question of species evolution was not really the focus of this study, but I can say that some of the plants alive then such as the seed ferns have no modern day equivalent, whereas the long, crazy-tall reed-like plants called calamites have modern day equivalents (or closest relatives anyway) in horsetails. (a fairly common plant in water filled ditches).
DNA analysis is probably not possible, however, I am certainly not an expert in that area. A lot of the organic material has been cooked and in the case of the peat, cooked and compressed to form... (you guessed it!) Coal. So that is probably a dead end I'm afraid.
No new species were found, but we did have some head scratcher "What the heck is that?" "I don't know" "Get a sample, we'll see what we can figure out later" kind of stuff! And no, I don't think we have identified everything yet...
Heh heh.. Thanks a bunch Cervantes!
When I was making my nightly visit to Slashdot... (no I shant admit the ACTUAL number of times I visit!) I saw the headline, sighed and thought, "Okay bucko, time to earn your keep!"
It's actually been a lot of fun to share our excitement!
Hi Richard!
It's a pleasure to be posting. I have been a super-ultra-long-time-gets-the-funny-all-your-base -jokes lurker for just about forever.
Part one of your question is asking if the catastrophic event of earthquake induced flooding be destructive to forest-floor plants. A very good question.
To answer that I'll steal some text that will be going on the website this Friday as written by Bill DiMichele to describe the ground cover plants and follow up afterward:
"Ground cover plants:
Plants inferred from their growth forms to have been ground cover are not common at Riola. This suggests that the soil surface may have been inhospitable to the growth of small plants, perhaps due to flooding.
One plant in particular, Sphenophyllum, was widespread throughout the mine but rare. Sphenophyllum (Images 51 & 52) is a sphenopsid, the same higher-level group that includes the horsetails. Like that group of plants, it has "node-internode" construction and its leaves and branches are borne in whorls. In this instance, however, the leaves are wedge-shaped, a distinctive attribute of these plants. Some Sphenophyllum species have hooks or barbs on their leaves, suggesting that they too formed thickets or tangles, and perhaps may have climbed other trees for support.
Another potential ground cover plant, a possible small fern or seed plant, is Sphenopteris (Image 53), which is rare in the Riola mine. Sphenopteris is characterized by small fronds that have small, variously lobed pinnules."
One reason to believe that the flooding, while catastrophic in the sense that it was sudden, may not have been particularly violent is the lack of strong linear orientation of both plants and logs, nor any preferred 'piling' of leaf litter and debris up against upright tree stumps. I personally would imagine the flooding of the forest to be in the multiple minutes category and not the 'large imposing' violent wave category. As Bill writes above, the ground surface may not have been conducive to thick luxuriant cover, but I also wonder to what degree the Sphenophyllum 'hooks and barbs' may have rooted them in place under flooding duress!
The second part of your question asks about the importance of smaller life being critical to an understanding of forest ecology.
You got that right! In modern forests the importance of 'smaller life' is undeniable.
In geology we are often forced by lack of data to fill in the gaps as best as we are able to infer. Or we are required to 'complete the puzzle' with the available puzzle pieces. Along those lines, much of the picture of these 300 million year old peat mires comes about through many many many individual finds and discoveries. A few insects here... an amphibian there... ground cover plants here... massive monster of tree there... a complete coal ball collection detailing plant diversities and general ecologies here... glimpses of many of these individuals (but not all unless you've got good karma) together in one spot there... etc.. Put all the individual puzzle pieces together and a cohesive picture starts to form.
For this particular study I feel pretty confident in saying that we are almost certainly missing big chunks of 'the little stuff'. For example, we may have seen some insect parts, but we can't be sure. Did they get swept away? Fly away? Hard to know. We are absolutely missing the entire ecological picture here and in that sense the answer to your question is a disappointing, "Nope, we don't have it all, so we don't have the honest to gosh whole picture"
But what this study does provide is some confirmation that the picture we have theorized about... i.e. we think the Pennsylvanian peat mire ecology looks like 'X' is correct. That the subtle variations in forest ecology that you would see walking down a hiking trail in your nearby state park ("Hmm, first I saw maples, and 300 feet later I saw a few oaks, and then the maples thinned out and the oaks were dominant"
Yes!
We should have a website with detailed pictures and explanatory text online this by this Friday at the Illinois State Geological Survey home page:
www.isgs.uiuc.edu
look for a link on the 'recent news' portion.
(now guess what I get to do all day tomorrow...)
Assassin bug asked nearly the same thing. We did find Eurypterid (http://en.wikipedia.org/wiki/Sea_scorpion) pieces mixed in with the plant fossils and there is the possibility of some insect parts (legs, etc..) in some of the 'hashier' areas of the roof.
But, as I mentioned to Assassin bug, we had a LOT of territory to cover in fairly short amount of time, so we had to concentrate on the dominant plant fossils.
Your speculation on the moveable critters in the system 'getting the heck out of dodge' when the ground dropped out from underneath them may well be true. I would hope that at least some died and stayed put! Time (to collect data) was our enemy here.
I should probably have mentioned this before, but we are very thankful that Peabody Energy allowed us into the mine to study and record this wonderful fossil forest. It costs them man power and time to shepard us in their mines and they have been very supportive of our efforts. Truthfully, without them extracting the coal in the first place, we would never have been able to see the steady unveiling (10 years time!) of this 300 million year old snapshot in time.
An excellent question Assassin bug,
I've had a few emails on the very topic.
Howard Falcon-Lang and Bill Dimichele did find Eurypterid parts and pieces for certain and in some 'hashy' areas we may have found insect parts but it was hard to tell. Truthfully, the study area was so dang large that we were forced to really 'make tracks' to cover what we could, I am certain short-changing areas of interest such as your own in favor of the dominant plant fossils. I think I described the task to one reporter as trying to make a map of all the store fronts in New York city in a few days of walking the city, ending up with your 'chinatown area' ' little italy area' etc..
A shame now in retrospect that we didn't make more of an effort to look for those other parts of the system... but oh baby did we have a lot of ground to cover!
We do have representative samples from the mine roof that are currently in the Smithsonian collection, and hopefully Grimalidi can snag some time to give them a look over.
Hi,
One of the authors here (Scott Elrick - geologist from the Illinois State Geological Survey). I would be happy to answer questions from folks... or at least try!
I can start by giving a basic overview of the discovery, what we found, and how it is important (to paleobotanists that is).
The location of the fossils is just to the south and west of Danville, IL, itself about 30 miles to the east of the University of Illinois, Urbana-Champaign (say hi to HAL when you come to visit). The forest was found directly above the Herrin coal seam in the Riola and Vermillion Grove coal mines, owned by Black Beauty coal (a subsidiary of Peabody Energy). The mines cover approximately 15 square miles and the study area was about 4 square miles... actually 1000 hectares. (I'm rounding up the square miles)
Okay, so what's so cool? If you are a geologist and read the headlines that have been popping up about the story, you may have scoffed and shook your head saying, "What do they mean largest fossil forest? A coal seam is nothing but the fossil remnants of a fossil forest. And a coal seam like the Colchester coal extended from Pennsylvania all the way to Oklahoma!" And you are correct! (This is my first exposure to the modern day media... and its been an eye opener! Give them credit, they do a pretty god job overall)
What is 'largest' about this fossil forest story is that it is the largest STUDY of a mostly entact fossil forest. Specifically one that is looking at the ecology of that forest. The largest study before this that looked at the overall ecology was about 25 hectares.. say about 1/10th of a square mile. So this study is an order of magnitude greater. The meat of the matter here is that we had an opportunity to examine a fossil forest at just a wonderfully huge scale and as a result were able to see subtle changes in the make-up of the forest as we walked the multiple miles of passageways in the mine.
The analogy is that previous studies were like blindfolded people examining an elephant. Each person has a wonderfully detailed and accurate description of his or her patch of the elephant, and when they compare notes a decent group consensus exists as to what the elephant probably looks like... but nobody has a chance to see the whole elephant. Our study is where we get to step back from the elephant a bit and take a pretty good peak under the blindfold at the whole animal. (I wont go so far as to say we are able to clearly see the whole thing as that is stretching the analogy. The point being it is an important and exciting step forward, but not necessarily a monstrous revelation!)
A couple of things to highlight.
First, the part that I find the coolest about work like this. In much of geologic science (field aspects more so), geologists look at vast spreads of time in small geographic slices. For example, standing at the rim of the Grand Canyon and peering across to the other side, your eye takes in millions of years of geologic time... but you are only able to see a thin 'slice' of each unit in profile. What does a particular rock unit look like 500 feet into the side of the canyon walls? The only way to find out is to drill a hole and take a core sample.
Geologic research, or in this case paleontological research, in an underground mine such as these coal mines is orthogonal to the norm above! At these mines, looking up at preserved trees and ferns in the mine ceiling, we were looking at single slice of time, a T(0) event, over a huge (relatively speaking) geographic area. That means that we were able to get a snapshot in time look at the forrest landscape of 300 million years ago. It's the 'worms eye' view of a fossil forest.
I should point out that the 'discovery' of this fossil forest was a gradual process. One of the responsibilities of the Illinois State Geological Survey is to try to understand the geology of the state of Illinois... and for us in the coal section that means coworker John Nelson and I (also one of the aut