Guest solius symbiosus Posted March 24, 2008 Share Posted March 24, 2008 I found this today. I have seen it a couple of times over the years, but always passed it up ... thinking it was a group of bivalves. Today however, found 5 of these in an area about the size of one square foot. They were sitting on a ledge of calcarenite that is inter tongued with a deeper water shale and limestone. The calcarenites were very shallow water/ beach deposits. If you look at the outcrop photo, you can see a clayey layer that was probably a storm deposit. They were found on the ledge at the contact of the flood stuff. They are from the Millersburg mb, Lexington lm. Late Middle Ordovician. Outcrop dorsal ventral x10 (as you can see, there is really no structure) x20 Link to comment Share on other sites More sharing options...
ShadyW Posted March 24, 2008 Share Posted March 24, 2008 I'm certainly no expert, so this is really just a random guess from me... but it looks like a plant seed of some sort. Every complex scientific problem has an elegant and simple solution... and it is wrong. Link to comment Share on other sites More sharing options...
Guest solius symbiosus Posted March 24, 2008 Share Posted March 24, 2008 It is from the Ord, so it is not plant material. Link to comment Share on other sites More sharing options...
Harry Pristis Posted March 24, 2008 Share Posted March 24, 2008 It is from the Ord, so it is not plant material. Hmmm. No structure suggests a trace fossil. How about an infilled burrow or nest chamber, excavated by a storm and cast upon the beach? I see some globular forms -- are those egg impressions? http://pristis.wix.com/the-demijohn-page What seest thou else In the dark backward and abysm of time? ---Shakespeare, The Tempest Link to comment Share on other sites More sharing options...
jkfoam Posted March 24, 2008 Share Posted March 24, 2008 Umm, Harry raises some interesting points to consider. When I first looked at it I thought maybe a Scyphozoa such as a jellyfish or sea anemone (Brooksella came to mind), but then I thought it had a mineral character to it. Could it be a goethite pseudomorph after pyrite or marcasite that had weathered badly. Scyphozoa fossils are really rare because of the unusual circumstance required for preservation JKFoam The Eocene is my favorite Link to comment Share on other sites More sharing options...
Guest solius symbiosus Posted March 24, 2008 Share Posted March 24, 2008 I don't think it is a pseudomorph. There is some pyrite in in the matrix of the surrounding rocks, but it is sparse, and the grains are small(<1mm). The only eggs I can think of would be some kind of Ostracoderm, but they have never been found around here. The globules are composed of silt sized grains in a clay matrix. If it is a trace fossil, the critter had a sophisticated systematic method if it was feeding. When I first saw this years ago, I thought it was a colony of bivalves with the original material dissolved away, leaving an internal mold. Whatever it is, It is rare to this area. This is just the 2nd or 3rd time I have seen this in 25 years, and the first time in multiples. Link to comment Share on other sites More sharing options...
Guest solius symbiosus Posted December 9, 2009 Share Posted December 9, 2009 I thought that I would bump this since we have so many new members, and I still haven't IDed the thing. It has been suggested that they are mamaleons from a stromatoporoid... but I don't think so. It has also been suggested that they are "algal balls". Grinding a thin section will probably give a definitive answer, but I kind of hate to cut the thing. Any ideals??? Link to comment Share on other sites More sharing options...
Terry Dactyll Posted December 9, 2009 Share Posted December 9, 2009 Solius Symbiosus.... Ive no idea what they are, but keep posting the geology lessons and photos of the strata's you come accross.......Thanks.... Cheers Steve... And Welcome if your a New Member... Link to comment Share on other sites More sharing options...
Shamalama Posted December 9, 2009 Share Posted December 9, 2009 Interesting fossil, Solius, Maybe some sort of coral or bryzoan? The Ventral side looks like a coral that started on a muddy surface like some Favosites that I've collected. Have you shown it to any "experts" beyond us? -Dave __________________________________________________ Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPheeIf I'm going to drive safely, I can't do geology. - John McPheeCheck out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/ Link to comment Share on other sites More sharing options...
frozen_turkey Posted December 10, 2009 Share Posted December 10, 2009 Looks like a fish's crushing mouth plate to me. Link to comment Share on other sites More sharing options...
Placoderms Posted December 11, 2009 Share Posted December 11, 2009 Interesting fossil, Solius, Maybe some sort of coral or bryzoan? The Ventral side looks like a coral that started on a muddy surface like some Favosites that I've collected. Have you shown it to any "experts" beyond us? I am leaning towards Shamalama's bryozoan idea but first could I get a side view? When I get home I'll look up somthing that may look similar and found in Upper Ordovician shale. Link to comment Share on other sites More sharing options...
erose Posted December 11, 2009 Share Posted December 11, 2009 Solius, Get your hands on a copy of this: OSGOOD, R. J., JR. 1970. Trace fossils of the Cincinnati Area. In Palaeontographica Americana, 6, Paleontological Research Institution, Ithaca, NY. I bought one about ten years ago from PRI. They certainly may have more. Link to comment Share on other sites More sharing options...
Guest solius symbiosus Posted December 12, 2009 Share Posted December 12, 2009 Interesting fossil, Solius, Maybe some sort of coral or bryzoan? The Ventral side looks like a coral that started on a muddy surface like some Favosites that I've collected. Have you shown it to any "experts" beyond us? It is not bryozoan or coral,There is no structure. Yes, I have shown it to a few people, but their areas of expertise is specific. I think that Harry and erose has hit on something. Erose, is there something specific in the journal that is similar? And, if so, could you enlighten, please? Link to comment Share on other sites More sharing options...
Redlichia Posted February 20, 2010 Share Posted February 20, 2010 It is not bryozoan or coral,There is no structure. Yes, I have shown it to a few people, but their areas of expertise is specific. I think that Harry and erose has hit on something. Erose, is there something specific in the journal that is similar? And, if so, could you enlighten, please? Interesting find,maybe are algae balls,not sure,or some type of preservation of jellyfish or sea anemone. Congrats! ->>>>> < Link to comment Share on other sites More sharing options...
New Members growlator Posted March 7, 2010 New Members Share Posted March 7, 2010 I hope this is a valid contribution- When I saw this fossil of yours I immediately thought of a worm feeding trace known as paleodictyon. A relevent publication may be "Treatise on Invertebrate Paleontology - Part W - Trace Fossils (1975)" Do a search for Paleodictyon on google books and you should be able to get a preview of the relevant pages within that book. Alternatively, here are some other links. Paleodictyon Wiki Google Image Search If not paleodictyon, perhaps it is some other related trace fossil. Whatever it is, I think it is fascinating. Also, hello to the forum, this is my first post! Link to comment Share on other sites More sharing options...
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