Field of Science

What is this? Fossil?



After reading my posts on tubular fossils (here and here), a reader sent me pictures of an object he found while walking on the beach near some cliffs in Lusby, Maryland (USA). Is anyone able to tell him what it is? Is it a fossil, or an inorganic structure? If it is inorganic, any ideas on how it could have formed? More pictures below:


11 comments:

  1. Coprolite? If so, probably mammal. Maybe small/medium carnivore.

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  2. Looks more like a burrow to me.

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  3. Burrow made by a new species of dwarf Palaeocastor...or some other type of burrow.

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  4. if not a dwarf beaver, then perhaps a scorpion? They build spiral burrows with oval cross-section, obviously not likely if it's from a marine facies however.

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  5. Toby - I don't think a coprolite would have that distinctive spiral form.

    Mike (if that is Mike) and Neil - is it common for fossilised burrows to be dissassociated from their original matrix like that? I've got pretty much no experience with trace fossils.

    One possibility that occurred to me was that it might be an eroded steinkern from a large gastropod - does anyone know if this is likely?

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  6. I don't know if it's common but it's certainly possible. Say the burrow is in mud and is filled in by sand that gets cemented during diagensis. The shale erodes away leaving behind a cast of the burrow.

    Steinkern is certainly a possibility although I would expect it to taper in one direction (and perhaps it does I can't quite tell from the picture).

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  7. The first thing I also thought of was a fossilized burrow. Its not a tube though since there are none of the typical markings (seen even is the tube is eroded away). It could the burrow of something that makes a lining, like mucus. That would keep it intact if it were from marine sediment.

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  8. looks like a quite nice fossilised burrow. Unfortunately, I can't find any that match it in the resources I have to find. Your local museum should have a good reference book tho, try them :)

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  9. its defintely a gastropod what is left after the calcium fades away from the sand it is in I have found many with this design it is for sure a large gastropod insides.. the outershell has eroded away

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  10. for you fossil,
    it's a worm with a shell.
    I am a french amator of fossil, and i have fossil the same.
    The name is "Tenagodus striatus" for the regular form, and "Tenagodus anginus" for the irregular form.

    I you want me to give you some pictures from this fossil, i can give you, please scribe me a mail to : "sixneith.sixneith@laposte.net, and scribe in the subject fossil.

    Bye.

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  11. the age is miocene, in the burdigalien, 16 to 20 million years ago.

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