Ordovician in Tennessee (Help!)

[Terri]

I learned the history behind the area I am collecting in now. It was actually briefly quarried a few years ago. When I walked onto the property I suspected to walk across the top of a hill, instead I walked down into the hill. I mistakenly assumed the area had washed out in the flood last spring, but they took out the topsoil and pounded up the rock for gravel. So it is not a natural outcrop, I suppose that explains the little pockets of shale (what I think is shale). There are several different "levels" exposed in about a 5 acre area that was worked.

Here a a couple of things found yesterday: In the first pic. maybe a couple of orthocones? You can see some of the "blueish" gravel, that I think is shale. The second, a couple of gastropods and the third what I suspect may be oil shale, don't know what the fossil is..

 

[Hajar]

Very pretty finds! I think I see burrow-fills in that lower photo, some filled with coarse material (sand?), others filled with fine-grained material now weathered out. If you can see distinct burrow linings they could be Palaeophycus and if not, perhaps Planolites.

 

[Terri]

Thanks Hajar! I'll have to do some reading on trace fossils.

 

[Architeuthoceras]

Nice pics of the Actinocerid, shows some cameral deposits, still can't quite make out the septal necks.

The bottom photo in the next set looks a little too coarse for shale, with trace fossils as Hajar noted. The flat topped gastropods are something akin to Rhaphistomina. In the top pic (low left) is a high spired gastropod, possibly Subulites. The thing above (hi left) may be a cephalopod or a crinoid stem, hard to tell for sure without a siphuncle. If it is a cephalopod the internal molds have shifted again.

Did they leave a wall in the quarry? a pic of that would be nice.

 

[Terri]

No wall, the sides are soil all the rock along the bottom, I do have some pictures though, I'll sort through them and post a few. It doesn't look like a typical quarry.

 

[Terri]

The first picture is looking up about a 30ft. grade, which is the closest thing to a wall there is and the sides must have really washed out during the flooding. In the second picture I'm at the top looking down, and the third is just a sample of the rock exposed across the bottom, I may have already mentioned but about 5 acres of exposed rock, practically every inch full of fossils. What I have shown you from the site is a very small sampling (trying to stay on topic) there's probably no more than an inch or two not covered in fossils most of them very small but in mass quantities.

 

[Architeuthoceras]

Thanks for the photos Terri, it really helps to see the collecting locality.

Only about 30,000,000 sq in. left to explore huh.

 

[DWhatley]

Kevin,
I am trying hard to learn and follow Terri's adventures but when you said there was a possible ceph or crinoid stem I tried to locate it. Is this it or the segmented part to the left of this?

 

[Architeuthoceras]

D, your pic is probably a Bryozoan, seen in the upper right corner of the pic below.

here is the Cephalopod/Crinoid

The segments look like internal molds of the chambers of a ceph shell but a few have slipped and are laying almost flat. I have seen a lot of crinoid stems look like this, but very few cephs, the siphuncle usually keeps them in line. I can't see any sign of a siphuncle in this fossil.


This is the hi-spired gastropod.


And this is a cross section of one of the "Flat topped" gastropods, the top is facing the upper right corner.

Hope these help.

 

[Terri]

Sorry about the quality of my photos ya'll! New camera on the way, but must wait until Christmas!

Thanks for the explanation Kevin, and your right (of course) after looking more closely, it is a crinoid.

D here are a few more examples of crinoids found at this location. Kevin please correct me if I am wrong in what I think I am seeing here.

In the center and top of first pic. a cross section of a crinoid? To the left and center of pic. a crinoid stem.

In the second pic. to the center and right crinoid pieces scattered around and to the left ?molds scattered around where the thin layer of (crinoid) sediment broke off.

 

[DWhatley]

I was hoping for some kind of soft bodied octop parts and noticed the Bryozoan could look like an octo or feather star (but not the stem ). Vicarious fossiling is becoming a fun sideline and your indulgence for dumb questions is much appreciated!

Looking at Terri's rocks is almost as much fun is going through a small plankton tow

 

[Architeuthoceras]

You are right Terri, excellent examples of most of the parts of Crinoids.

Crinoid Morphology

 

[Terri]

Thanks Kevin! That's a great link, hadn't ran across that one.

 

[Terri]

This is a curious little fossil, looking closely, I think it could possibly be a nautilod, it appears to be a phragmacone with a little bit of a living chamber (I could be very, very wrong) It's about 2cm. long(lost my ruler again) I don't see a siphuncle but something weird on the end.

 

[Architeuthoceras]

Looks like another little C. B. , a little weathered on the body chamber and the first few chambers missing.

The thing on the end is curious, can't make anything out of it.