View Full Version : Fossil Info Requested
Reighan Aug 12th, 2006, 08:04am Hi! I'm Reighan. I haven't posted until now because there hadn't been any cephalopods in the local glacial deposits I've been studying. (I'm a beginner.)
But this one seems to be an orthoconic nautiloid?
http://i103.photobucket.com/albums/m142/Reighans-Rocks/crincepha.jpg
And then there is this, which looks like aragonite. Is it some kind of cephalopod?
http://i103.photobucket.com/albums/m142/Reighans-Rocks/wuzzat2.jpg
http://i103.photobucket.com/albums/m142/Reighans-Rocks/wuzzat2d.jpg
http://i103.photobucket.com/albums/m142/Reighans-Rocks/wuzzat2b.jpg
Any comments will be appreciated! Thanks in advance.
Reighan Aug 12th, 2006, 08:10am Ooops. I'll figure out how to resize pictures... :oops:
cuttlegirl Aug 12th, 2006, 08:10am :welcome: , I 'm not a fossil expert so I can't make any suggestions for you, but you've come to the right place!
Reighan Aug 12th, 2006, 09:35am :smile: Thank you! There is a lot of very good reading here, so I'll be visiting frequently.
Architeuthoceras Aug 12th, 2006, 10:36am :welcome: Reighan.
The first photo is probably an orthoconic nautiloid as you thought, a little out of focus, but it looks like septa with some cameral deposits and a siphuncle.
I dont know about the fossil in the other 3 photos, it looks more like a crinoid stem than a cephalopod shell.
Reighan Aug 12th, 2006, 10:59am Thank you, Kevin. The material from the glacial deposit is providing an unending educational experience. So far the crinoidal things have been Carboniferous calcite-in-limestone and some Ca-Mg impressions, so the aragonite would be a new one... Thanks again!
Reighan
Phil Aug 17th, 2006, 10:12pm Glad you made it over here Reighan, and welcome to TONMO.
Definitely a nautiloid that first one, and a nice find too. Was that your first from Wales?
Reighan Sep 11th, 2006, 10:06am Hi, Phil
Just popped in and found this message. Sorry it took so long to respond. I've been bogged down with rocks and minerals. (BTW, the 'aragonite' in the non-ceph above is quartz <groan>.) (So much to learn...)
The nautiloid above was my first, and so far is the only one. Before I found that, we'd found only corals, crinoid bits, and brachiopods in Carboniferous limestone, which is why I noticed the nautiloid--because of the matrix! I'd never found anything at all in New Jersey, so the glacial drift on this beach is overwhelming (but wonderful). The more Mike & I learn, the more things we recognize and find, so... there are probably cephalopods out there somewhere. The most recent good 'un is a bit of chalk cidaroid.
ATB,
Reighan
Phil Sep 11th, 2006, 11:03am Well, it may be your first, but it's certainly a good place to start! Well done! Keep going, you'll get a corker one of these days, trust me.
Architeuthoceras Sep 11th, 2006, 02:03pm It is possible that the other fossil is the silicified siphuncle of an Actinocerid. :wink:
Reighan Sep 13th, 2006, 04:40pm Thanks, Phil, for the encouragement. :smile:
And, thank you, Kevin, for the suggested ID. Sorry about my misidentified mineral. :oops: I Google-ed 'Actinocerid', and followed a lot of tangents, and learned quite a bit, so thanks for that as well.
ATB,
Reighan
Phil Sep 13th, 2006, 08:30pm I just tried to find a good basic description of Actinocerid nautiloids but to my horror found that the superlative website Paleos has been taken down for good! Oh no, this is terrible news.
I believe that the siphuncle is sub-ventral in these forms and tends to bulge out into each chamber like a inflated ring; these rings also contain heavy cameral deposits used as counterweights to control the orientation of the conch.
Hopefully Kevin will have a much better description.
Reighan Sep 13th, 2006, 08:51pm Thanks, Phil. That helps. Even considering my lack of knowledge, there didn't seem to be a lot of information on Actinocerids. Initially I got the impression they were all Australasian, which would have been a stretch even for this drift. :lol: But if mine is an actinocerid, then it's probably Silurian? 8-)
aNmLlUvR09 Sep 13th, 2006, 08:57pm this is absolutely the most interesting message board i've ever been on...i dont understand half of what anyone is saying and its so thrilling! :)
Phil Sep 13th, 2006, 09:23pm Thanks, Phil. That helps. Even considering my lack of knowledge, there didn't seem to be a lot of information on Actinocerids. Initially I got the impression they were all Australasian, which would have been a stretch even for this drift. :lol: But if mine is an actinocerid, then it's probably Silurian? 8-)
Well, according to Clarkson's book the Actinceratina were a Suborder of Orthoceratid nautiloid that thrived from the early Ordovician (when most of the Orders and Suborders appeared) but became extinct in the early Carboniferous. I'm pretty certain that their distribution was global and I'm sure that examples of actinceratids have been found as wide afield as Utah, Japan and Europe. Rayonnoceras is a particularly well known form. Maybe it is worth asking which nautiloids are known from Wales on Joe and Lucy's site?
this is absolutely the most interesting message board i've ever been on...i dont understand half of what anyone is saying and its so thrilling! :)
Don't worry, old chap. I've no idea what people are talking about on here either most of the time, and I've been here for four years! :wink:
Architeuthoceras Sep 14th, 2006, 12:01am Here I go using some more big words...
Actinocerids are characterized by usually having cyrtochoanitic septal necks, convex/bulbous connecting rings, annulosiphonate endosiphuncular deposits with canals running radially from a central hollow, and cameral deposits that can show up on all sides of the chamber.
alot of times the only thing preserved is the siphuncle which would basically look like a straight string of pearls.
below is a photo of a longitudinal section of Rayonnoceras, an actinocerid from the Mississippian of Utah. Rayonnoceras was one of the last of the actinocerids, they are more a Silurian to Devonian ceph.
Reighan Sep 14th, 2006, 07:52am aNmLlUvR09: I usually have to read everything with heavy use of books and a web browser. :smile: I try to do the same thing when I post but, as you can see from this thread, I still get things very wrong sometimes. :oops:
Phil: I'm passing the information on to Joe and Lucy. It kinda puts experts at a disadvantage when I provide inaccurate data... :oops: , so I'm grateful for the information I get here. Makes life easier for everyone. Another complication is that we're not sure where my rocks are coming from. (Any glaciologists out there?) :hmm:
We're currently focused on 'new1', a rock with lots of bits (mostly brachs, no obvious cephs) showing on the surface that I haven't seen in anything else I've found. (I'm hoping it's a very old one; at least it is a very different one.)
Kevin: Thank you for the very useful big words :smile:
and for the picture. I hope I can use the terminology some day... it's more accurate and it would reduce my verbosity. :grin:
Reighan
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