Carmel Church Day 3

It was a beautiful day today, and we spent about 9 hours at the site. We’re hitting a lot of bones now, even though we’ve only uncovered about 0.2 square meters. In the photo above, a rib (No. 3 from yesterday) is visible just to the right of center. The round object at bottom center is yesterday’s No. 1, a tail vertebra. Between it and the scale bar are three new bones, all apparently tail vertebrae. Note the shiny object just to the left of the vertebrae:

This is the Carcharocles megalodon tooth I tweeted about earlier. It’s fairly unusual for two reasons: it’s apparently not reworked (most of our C. megalodon teeth are), and it has been shattered. I’ve never seen this kind of damage in a tooth before, with the enamel actually peeled back around the breaks. I believe this is post-burial damage, and I suspect we’ll find a large rock underneath the tooth, but the tip also appears to be broken; that could be from biting into bone. Incidentally, the round object at the tip of the scale bar is a large fish vertebra.

Tim started expanding our pit to the south into the weathered part of the exposure, apparently wearing “danger red” to warn the flies and mosquitoes not to mess with him:

It’s tough to get good bones out of the weathered material, but Tim found several decent fragments, including this very nice fish vertebra with the neural spine intact:

The weather forecast looks good through the weekend, and if I can ever find a gap in the bones we may be able to make our first jacket early next week.

This entry was posted in Carmel Church Chondrichthyans, Carmel Church Osteichthyans, Carmel Church Quarry, Chesapeake Group. Bookmark the permalink.

4 Responses to Carmel Church Day 3

  1. Doug says:

    Let us know if there is a rock under that tooth. But how would the enamel be peeled back like that?

  2. Alton Dooley says:

    That’s what I’m not sure about…

    Unfortunately, I’m almost certainly going to take the tooth out in a jacket with the vertebrae, so we won’t know if there’s a rock there until the jacket is opened. That might be awhile.

  3. 220mya says:

    Irmis & Elliott (2006) described extensive longitudinal cracking of enamel from actualistic abrasion experiments. I suspect its a normal thing from exposure on the sea floor, etc.

    Irmis, R. B., and D. K. Elliott. 2006. Taphonomy of a Middle Pennsylvanian marine vertebrate assemblage and an actualistic model for marine abrasion of teeth. Palaios 21:466-479.

  4. Alton Dooley says:

    Interesting article. We see that type of abrasion a lot, especially in reworked teeth (and especially in rays). Much of the damage they describe only shows up in SEM images; I wonder if we would see the same in non-reworked teeth?

    The don’t figure the kind of splitting we see in this tooth. It occurs to me that I’ve seen numerous examples of C. megalodon teeth split longitudinally (although not shattered). I wonder if these large teeth are either prone to cracking this way when they hit into hard bone, or perhaps when exposed to seafloor conditions (I think the latter is more likely).

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