Please ID shark tooth, poss shark vomit(?), fish coprolite

[Lone Hunter]

Stopped by a new home construction site, a tad NE of DFW airport, Eagle Ford Kef, so far just levelled with road cuts.  Stumbled upon this shark tooth and I lack the experience to ID it.  Next up the rock which is what I think is fish coprolite, it weighs nothing, doesn't look like any shark coprolite I've seen, and there were no other rocks that looked even close. Lastly, and I might be way off, I'm pretty sure is shark related, my first impression was it looked like a puddle of barf. These were just the biggest peices the rest was shattered. I know sharks vomit so that was just a thought , it has the makings of coprolite but lacks shape, eager to learn what it is!

[ThePhysicist]

First tooth is Cretolamna appendiculata. I don't think the second item is a coprolite, but it may have a fossil in it. The last grouping is simply a collection of fossils cemented together; you will likely find lots of cool microfossils if you break them up.

[Lone Hunter]

Thank you for the ID on tooth!  As far as the last pics, not sure I'm convinced yet, I have a ton of fossils cemented together, there's always at least one that's whole or identifiable. Everything on these looks already chewed up, some to the size of a grain sand. Also, I walked an area the size of football field and it was void of anything else, no sign of fossils, no dirt or concretions that color, no fill dirt or rock, that stuck out like a sore thumb. That's why .my thoughts went to something deposited it there, and shark tooth was only evidence. 

[ThePhysicist]

Broken fossils does not imply they were chewed, and besides, sharks don't masticate. Also, the shark your tooth belonged to would not have eaten shells, rather it would have eaten fish, other sharks, marine reptiles, etc.

 

As for this high concentration of fossils occurring in one spot, that's not unusual. Here are pieces of matrix found by @BudB:

It can be simply caused by natural processes:

@Uncle Siphuncle:

"Teeth often end up in lenticular lag deposits that are limited in extent.  Essentially a shallow depression in the sea floor that accumulated teeth etc when currents and/or wave action swept them into the lowest spot in the vicinity.  This is a common scenario in all ages of marine sediments.  I once found a 2 x 3 foot Eocene lag deposit that contained dozens of inch plus Galeocerdo and Brachycarcharias plus lots of smaller shark teeth, cutlass fish and barracuda teeth, my best ever shark vert, croc osteoderms, teeth and a nice croc vert, plus 50 big, thick gar scales.  These little lenses can be wet screened with a course and fine mesh screen to reveal treasures of all sizes."

Edited March 28, 2021 by ThePhysicist

[Lone Hunter]

Now I understand, it was hard to grasp that scenario in such a tiny spot.  Such a steep learning curve!  Thank you for the education!

[GeschWhat]

If these were found in the Eagle Ford Group, I'm pretty sure that is a coprolite in the second photo. They often have a lot of inclusions. Coprolites from that formation are generally light colored and very porous. So if it has fecal origins, it will stick if you touch it to the tip of your tongue.  I know that may sound gross, but it is a method commonly used in the field (in some formations) to differentiated coprolites from concretions. It also works on bone depending on the fossilization process and type of bone. If you are not that brave, just touch it with wet fingers. It should feel sticky.

 

The slabs are commonly referred to as hash plates. Fossil vomit (aka reguritalites) are usually isolated clusters and consist of bigger chunks. That is unless you are talking about animals like an octopus. They tend to project their scraps (and their poop). They gather in piles outside their hiddy-holes and are known as middens. Here are a few examples of what I believe to be fossil vomit in my collection. They are all from the UK, but might give you an idea of what to look for if you are interested in the "fun" fossils. 

[Lone Hunter]

Somehow I missed your reply and I'm just now seeing it,  I forgot all about the lick test, thank you so much for reminding me because that gave the answer!  It stuck like Velcro.  Appreciate all the info and so enjoyed that site and looking at your vomit. 

[JohnJ]

Consider also that some zones of the Eagle Ford are full phosphatic nodules.  They notoriously imitate fossil-like objects, shatter like the roots of shark teeth, and range from cream to jet black in color.

[Lone Hunter]

How would I tell a phosphatic nodule from an ironstone nodule or one of many types of concretions around here?

[JohnJ]

2 hours ago, Lone Hunter said:

How would I tell a phosphatic nodule from an ironstone nodule or one of many types of concretions around here?

You can easily scratch or break these phosphate nodules.