Carnivore Coprolites & Tracks

[ErikHertz]

Here are a few specimens that have been poo pooed by collectors.  As I understand it carnivore coprolites like this need a "soft landing" They are produced in water and sink into the silt where protected as they fossilize. The holes are caused as the item surfaces and is exposed to the ocean tiny bivalves attach themselves to obtain minerals. Many have holes only on the side that was exposed. And others have no holes at all having never been in the ocean. The natural migration of barrier islands on the east coast is to move to the south west, this action is like a bulldozer track as the top moves west and south the contents sometimes  appears on the beach surface. Most fit into a specific type and all are smaller than a big dog, more like a cat or small dog sized creature, but none bigger. if they were a type of Coquina there would be larger specimens, there are none. There are however all sizes and types from different periods of Coquina from tiny pieces to hundreds of pounds.

There is evidence of shell fragments and often it appears the sample has landed on decaying vegetation or partially wrapped around a stick.

 

I even have one that has fragments, a termination point, obvious vegetation impression on one side and a foot print on the other side.  I have pressed a piece of clay in to each side  as a reverse study. In the first picture he foot print is less obvious than the vegetation impression. But when the excess is removed it reveals a triangular webbed clawed print.

[Gizmo]

This one's from the Cooper river, SC. From a dive trip last year.

 

 

[GeschWhat]

On 3/18/2020 at 7:20 AM, ErikHertz said:

Here are a few specimens that have been poo pooed by collectors.  As I understand it carnivore coprolites like this need a "soft landing" They are produced in water and sink into the silt where protected as they fossilize. The holes are caused as the item surfaces and is exposed to the ocean tiny bivalves attach themselves to obtain minerals. Many have holes only on the side that was exposed. And others have no holes at all having never been in the ocean. The natural migration of barrier islands on the east coast is to move to the south west, this action is like a bulldozer track as the top moves west and south the contents sometimes  appears on the beach surface. Most fit into a specific type and all are smaller than a big dog, more like a cat or small dog sized creature, but none bigger. if they were a type of Coquina there would be larger specimens, there are none. There are however all sizes and types from different periods of Coquina from tiny pieces to hundreds of pounds.

There is evidence of shell fragments and often it appears the sample has landed on decaying vegetation or partially wrapped around a stick.

 

I even have one that has fragments, a termination point, obvious vegetation impression on one side and a foot print on the other side.  I have pressed a piece of clay in to each side  as a reverse study. In the first picture he foot print is less obvious than the vegetation impression. But when the excess is removed it reveals a triangular webbed clawed print.

I really, really hate to poo poo these, but I don't think you have doo doo. They look more like internal casts. 

[GeschWhat]

Nice one @Gizmo!

[ErikHertz]

You seem to really know your stuff!  "Internal cast" I will have to google that. 

 

But what about the one with the reverse study in clay showing vegetation on one side and a foot print on the other?

[GeschWhat]

29 minutes ago, ErikHertz said:

But what about the one with the reverse study in clay showing vegetation on one side and a foot print on the other?

I don't think that is from vegetation. Most likely those groves were left by boring creatures. I'm guessing the stones have a high calcite content, making them fairly soft. Another possibility is it could have been formed when the sediment landed on broken bits and bobs on the sea floor. Those, being softer, likely dissolved or eroded away due to sand/wave action.

 

The I love that you did an imprint using clay! I did that once to a "coprolite," except I used model magic. I thought it might have had a footprint in it. Unfortunately, it likely wasn't a footprint nor a coprolite. However, I am determined. Someday I will find a coprolite that has been stepped in!  

 

Keep looking, I'm sure you will find a coprolite someday. 

[ErikHertz]

Thanks, you too know your stuff!!! I wish you could see this one. The print is less obvious but its there! it shows movement and claws and webs, it also is shaped as if it has been stepped on heal to toe.  The vegetation impressions on the other side are only on the surface and do not penetrate and if you look closely you can see the vegetation layered and various shapes, Oh and this one never made it to the ocean or it would have modern bore holes, which I am quite familiar with. 

 

I am glad you like the clay idea, it really reveals details that are easier to understand when in positive. It is so much easier than a plaster cast and can be fired and made permanent. You are the second expert to say its a cool idea.

 

I have asked this question but never got an answer, If it was a coprolite that was stepped on , What is that called in your field?

 I uploaded a edited picture to show the outline of the foot print.  I recognize and appreciate your knowledge, but I am not convinced.

 

[abyssunder]

Hello,

In my opinion the chance for coprolite might be very low for the samples posted. I would agree with Lori's remarks. There could be ichnofossils as tracemakers, as I see correctly.

[Bone Daddy]

I find a lot of "holey rocks" like the smaller ones in the photo. I have a box full of them that I find on Gulf Coast beaches. I think they are weathered and wave-tumbled limestone rocks that have experienced preferential weathering of less-robust components, which results in voids. These rocks are fossiliferous, so I expect the voids are from softer, less-mineralized materials eroding or dissolving out.

They are interesting in appearance and some have suggestive shapes. I pick them up because New Age practitioners called them "crick stones" or "fairy stones" and they actually pay money for the larger ones with appealing shapes. I don't share those beliefs, but I am more than happy to trade them my beach rocks for cash.

 

I believe the majority of these are Miocene/Pliocene in age.

 

Just my two cents.