Pica Posted October 11, 2013 Share Posted October 11, 2013 Hello All, Can anyone ID this warn specimen? I think It's a large reptile tail vertabrae. Found in Barrington, Cambrideshire recently... Not sure if the hexagonal appearance is due to erosion or not. Any clues much appreciated. Best Pica Link to comment Share on other sites More sharing options...
paulgdls Posted October 12, 2013 Share Posted October 12, 2013 (edited) Pica Looks like an ichthyosaur vertebra. If from the Oxford clay its Ophthalmosaurus, if from the Kimmeridge clay its likely to be either Ophthalmosaurus or Brachypterygius. The vertebrae a few infront of the tail bend become wide and the rib attachment moves up the side of the centrum so would look like your find in terms of shape. Anterior caudal of Ophthalmosaurus found today in the Oxford clay for comparison and a pre tail bend vertebra (as found) from the same species in anterior, dorsal (showing the neural canal and neural arch attachment points) and ventral views. best wishes Paul Edited October 12, 2013 by paulgdls Link to comment Share on other sites More sharing options...
Pica Posted October 12, 2013 Author Share Posted October 12, 2013 Paul, Fantastic! Thanks so much for the ID. I think it's Kimmeridge clay but it was on a heap of spoil so its not like I pulled it out of its origin. Though in a chalk pit 80' deep... Good work! I prefer yours... Don't s'pose you wanna swap ;-) Thanks again Pica Link to comment Share on other sites More sharing options...
DE&i Posted October 12, 2013 Share Posted October 12, 2013 (edited) Hi Pica, Well done with your find i think its most likely to be Ophthalmosaurus , the only exposures of Kimmeridge clay itself i know of is a thin band around the Fens in Cambridge im not aware of any at Barrington. Regards, Darren. Edited October 12, 2013 by DarrenElliot 1 Regards.....D&E&i The only certainty with fossil hunting is the uncertainty. https://lnk.bio/Darren.Withers Link to comment Share on other sites More sharing options...
Pica Posted October 12, 2013 Author Share Posted October 12, 2013 That's tremendous! I really had no idea. I took it to Sedgwick and they were inconclusive. Thanks for taking the time over a second rate specimen Pica Link to comment Share on other sites More sharing options...
paulgdls Posted October 13, 2013 Share Posted October 13, 2013 Pica/Darren Take a look at this description of the geology: http://jncc.defra.gov.uk/pdf/gcrdb/GCRsiteaccount190.pdf Doesn't mention anything about Oxford or Kimmeridge clay. Could it be from the Gault or Greensand? If you find the jaw I'll do a swap. Paul 1 Link to comment Share on other sites More sharing options...
Pica Posted October 13, 2013 Author Share Posted October 13, 2013 Cheers Paul, Sorry, I'm still learning about the geology and proper descriptions of it as the forum is no doubt aware. Greensand, yes - this is what attracted me to the site in the first place... if I find the jaw it'll be a miracle; I can't find legitimate access to the quarry and I don't much like being chased up hill when carrying sacks of rubble! I suppose I could always sneak in dressed as a boulder and just move very slowly?! Seriously though, I am desperate to get back in so I'm looking for a field trip heading that way. Does anyone know how to get access? I'm ignorant of that too! Thanks again Pica Link to comment Share on other sites More sharing options...
paulgdls Posted October 13, 2013 Share Posted October 13, 2013 Hi Pica, Very rare bits then from the Greensand. Re. being chased uphill. Keeps you fit, but I guess the adrenaline rush might be a bit severe. cheers Paul Link to comment Share on other sites More sharing options...
DE&i Posted October 13, 2013 Share Posted October 13, 2013 Pica/Darren Take a look at this description of the geology: http://jncc.defra.gov.uk/pdf/gcrdb/GCRsiteaccount190.pdf Doesn't mention anything about Oxford or Kimmeridge clay. Could it be from the Gault or Greensand? If you find the jaw I'll do a swap. Paul Hi Paul, As you know i read that PDF so was a little confused as to the actual geology of Barrington , there is some Icthyosaur finds donated from the quarry at the NHM , they were found about 50 meters below the chalk with the chalks age around 90 million years . Ive never heard of Icthyosaurs found in a chalk enviroment , would that be quite rare. Regards, Darren. Regards.....D&E&i The only certainty with fossil hunting is the uncertainty. https://lnk.bio/Darren.Withers Link to comment Share on other sites More sharing options...
Kosmoceras Posted October 13, 2013 Share Posted October 13, 2013 Hi Darren, A few very rare ichthyosaur fossils have been found in the chalk, 5 species in total from the Cretaceous all incomplete fragmentary bits like vertebrae, teeth or other small bone fragments. The most comprehensive section was part of a skull 900mm long. They are more common (well, still very rare) in the Cambridge Greensand, a type of basement bed in the chalk. What I have found with Barrington is that the Boulder Clay which rests on top contains Jurassic erratic fossils such as belemnites from the Oxford Clay - so could it be from there? Regards, Thomas Link to comment Share on other sites More sharing options...
Pica Posted October 14, 2013 Author Share Posted October 14, 2013 Hi Darren and Thomas, just to add to the mystery, I found the bone on top of a pile of rocks that could have been from anywhere, but I assumed these where dug out of the floor which is Cambridge Greensand. The heap also yielded large ammonite fragments in something resembling a very hard yellow chalk, large flint sponges and huge concretion fragments. I was like a kid in a sweet shop. If it hadn't been 35 degrees in the glare of a chalk pit, I might have stayed longer. can't wait to return and am working on access. Best Ben Link to comment Share on other sites More sharing options...
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