Ordovician in Tennessee (Help!)

[Terri]

Thanks Kevin, I knew you could calm down some of that pesky "informational noise" bouncing around in my head, any chance of an id. on the brachiopod? (I've looked) can't seem to find anything exactly like it.

 

[Terri]

It has been about a month and a half since I was out, while there are many things for people to do in the snow out here, looking for fossils is not one of them.

I feel your pain!

ps: Don't you folks back east ever sleep at night?

A late evening trip to Starbucks took care of that!

 

[DWhatley]

There are very few times there is not coffee in the coffee pot at my house. It is not always freshly made but the microwave is inches away . I suppose I will have to keep more normal hours if this temporary job thing works out tomorrow.

 

[Terri]

: any chance of an id. on the brachiopod? (I've looked) can't seem to find anything exactly like it.

Here is a pic of what I think this brachiopod would have looked like before the outer shell wore away, Rafinesquina is the closest matching brachiopod I've found but haven't found a pic. or reconstruction of a cross section

 

[cuttlegirl]

The next two pics. I just think are cool, the first a gastropod and the second...ummm , a cross section of a brachiopod?

That is an amazing fossil of a brachiopod.

 

[Architeuthoceras]

These brachiopods have a convex valve and a concave valve, hard to tell from the pics which is which, but you seem to have the inside and outside of both.
The fine ribs are on the outside and the hinges and/or brachidium are on the inside. I don't know much about brachs, but Rafinesquina or Strophomena are a good bets.

 

[Terri]

Thanks Kevin! Between the two I 'm leaning towards Strophomena.

 

[Terri]

That is an amazing fossil of a brachiopod.

Thanks CG, it's still out in the rocks where I found it, I was afraid I would break it. After looking at it again (when the weather allows) I think I will be able to collect it.

 

[hallucigenia]

That last picture with the brachiopod rubble reminds me of some of the Ordovician deposits I've seen in Indiana in the last couple of years -- I think the locality was called South Gate Hill. Seems likely to be a related formation.

Also, I think that in addition to all those big strophomenids I see a couple of rhynchonellid brachiopods as well -- lower left quadrant, see the ones with the deep ribs on them? Another common sort that one often finds as complete specimens in rocks that look like this, rather than single valves, and they preserve very nicely.

I totally want to take my lab class down to these deposits for their field trip in the spring. Those Maclurites specimens are absolutely gorgeous, they look like what we have in the museum, and those are some very nice complete crinoid stems as well. Wow!

 

[Terri]

Thanks Hallucigenia, in post #103, Kevin pulled together the geologic information for this location, Sandbian, Late Ordovician. As you can tell if you've read much of this thread, I'm not an "ologist" of any sort. I rely heavily on Kevin for all technical stuff.I'm not very good yet at describing fossils (properly) or dealing with maps.

I wasn't sure which picture you were seeing the rhynchonellid brachiopods in, would these be an example?

 

[Terri]

Here are a couple of gastropods along with what I think may be some ceph parts just to the left of center.

 

[hallucigenia]

Yes, those are rhynchonellids. (in #212) That's a nice slab, too.

I guess this is about twice as far as our scheduled distance to go on the field trip... pity, it's similar to the site we're going to hit near Bloomington but way better. I'm seriously coveting those Maclurites specimens there.

 

[Terri]

Oh no! This location certainly is a great place to learn from, (with the help of everyone here at Tonmo). There is just so much, nothing fancy, just what I would imagine to be a thriving late Ordovician sea bed. There's one area of the "quarry" where I'm finding all the gastropods, Haven't even scratched the service yet.

 

[Architeuthoceras]

A great brach plate there Terri! In the new gastropod pic, looks cephalopodish on the left (I was trying to make an Asaphid trilobite out of it but couldn't), something on the right at same level (maybe slightly lower) and just to the left of the top snail, probably just parts of larger snails.

I wish I had a couple of boulders of that rock to see me through the winter.

 

[Terri]

The really cool thing about that brach plate Kevin, is that it looks like at one time to have extended over a really large area I'm finding little pockets scattered around the exposed rocks there and all the brachs weathered out of the matrix just laying around.

I also was trying very hard to make something cephalopodish out of that rock, I have to have one to throw in every once in a while so I can sort of stay on topic. I was really confused with the lack of cephs here, I'm used to finding them on top of naturally exposed outcrops like those at the beginning of this thread, but after learning that some of the rock had been crushed and hauled off it made a little more sense, I think there are a more to be found there though.

I'm working on putting a series of pics. together to give you a better idea of the exposed rock I am looking at. Most of the gastropods are down in the lowest level and the brachs in a different area, I've found nautiloids in both, but the few Gonioceras are in the area where all the brachs are, anyway I'm working on that.

Have you ever ran across anything you believed or know to be chepalopod trace, as in touch or grazing marks?