Illinois, Iowa, and Nebraska Part 2: Fossils

While I was in Columbus, Ohio I got very excited about fossils.  Really, I'm always excited about fossils, but I was reminded of them and saw some maps of where they can be found in the US.  So I decided to make fossil hunting one of my goals for the trip across the Midwest. 

For a little background, here is a chart of Geologic Time (thanks National Park Service!)

First stop was the Fossil and Prairie Park Preserve in Rockford, Iowa.  This is an old abandoned brick factory where they dug up Prairie clay and baked bricks.  In the process of digging they found a lot of not-so-great clay that was full of sea shells from the Devonian Period.  When they closed up shop, they opened the area for fossil hunting.  It's unusual in that it's free and you can keep anything you find, which is exactly what I wanted! Here's the old clay pit and the kilns. 

I found a bunch of brachiopods (think miniature scallops) and a few pieces of coral.  Nothing too crazy, but I definitely had a good time hunting around. It's neat to think I was finding things that were alive over 300 million years ago, long before the dinosaurs, when land-based life was essentially a few salamanders!  Unfortunately, the high-end washing station (water spigot) was closed, so I stuffed my fossils in my pack and headed west.  I'll have to post more pictures once I get them cleaned up. 

My next stop was a bit of a detour, but I was excited about it.  Ashfall, Nebraska is a spot where a whole bunch of volcanic ash choked a bunch of animals, and they all died intact within a matter of weeks or months.  This was only 12 million years ago (in the Tertiary Period) so there are horse, rhino, and camel relatives in the fossil bed.  It's an ongoing research site, so you can watch scientists excavating the fossils in a big shed they've built over the site.  Did I mention that I was excited?  Unfortunately, this is what I found when I got there:

I was 15 minutes too late!  They were closed for the day, and not opening again until the afternoon the following day.  I couldn't justify hanging around that long, so very sadly I continued on my way. 

Still determined to see some large mammal fossils, I next headed to the Fossil Freeway in South Dakota and Nebraska.  This time I planned ahead and checked park hours.  It's after Labor day, so a lot of places are closed.  One website claimed that the park was open, but when I arrived, I found that the hours had been changed: 

I was starting to fall into despair!  Luckily just down the road I found my last real hope still open.   The Agate Fossil Beds in western Nebraska.  Similar to Ashfall, the fossils here are from the Tertiary period, roughly 20 million years old.  Early rhinos, a big dog-like thing, plus a giant wild boar and some creatures that are even weirder all died around a small dried-up pond during a severe drought.  And across the valley there are giant corkscrew fossil casts from the dens of ancient beavers who lived in colonies like today's prairie dogs. The excavation is halted for now, but they've left some fossils in place, so beyond the visitor's center, I was able to go up to the bluffs and see bits of bone sticking out.  Super cool!

Here's a picture I took by laying on my belly and wiggling into a small cave in the cliff face, to get really close to one of the fossil bones.  I wonder if this is a rhino? 

Next over to the beaver dens:

And finally, a picture just to show how truly desolate this area of the country is.  The cornfields are long gone here in the very western part of Nebraska! 

All told, I'd call my fossil hunt a success!  But I'll still be looking for more as I head into Colorado and Utah...