Squeezing Water From Stone. A Summary of My July/August Trips Across Cretaceous Texas!

[Mikrogeophagus]

With time running out before the start of the school year, I decided to spread my attention across three DFW formations to get a little taste of what each has to offer. Instead of shooting out a handful of smaller topics, I've decided to combine my trips into a single larger post. I wouldn't say any individual find is a jaw-dropper or museum-worthy, but they, all together, give a nice glimpse into what each formation can yield.

 

In order from oldest to youngest:

 

Goodland

 

This adventure took place in Oliver Creek with the Dallas Paleo Society. It's a regular spot for the group on private property. The site is well known for its plethora of echinoids and highly sought after Oxytropidoceras (still working on the pronunciation) ammonites. A huge crowd of hunters arrived in Justin for the meet-up. I was worried it would be too crowded for the creek, but there was plenty of elbowroom and something for everyone. I'd say about half of the people spent the morning scouring the gravel beds whereas the others got to hammering away in the limestone ledges. Once my brother and I found the good layer, we were nonstop working out urchins and ammonites. The echinoids (A) were literally everywhere and preserved in great condition. We came out with a baggie full of them, but left many more behind. It was pretty easy to find ammonite fragments too. However, finding a complete ammonite with at least a little structural integrity was a tougher challenge. Luckily, fortune was on our side and we came away with four decent Oxytropidoceras's (B). The two pictured below are the largest and prettiest ones. Prepping them will be a challenge though. They are too fragile for the hammer and chisel, but a little too tough for my new dental pick (I bent it a bit already ). Along with these, we also got a neat selection of gastropods and bivalves (C). The Society continued on to a second location, but we decided to call it a day early since my brother was a bit tired of the heat and rock dust.

 

A). Several Holaster whitei from the Goodland Limestone. The ones straight from the ground have amazing preservation. One urchin is covered in oysters (Plicatula?). A coating of b72 gave them a nice sheen.

 

B.1). An Oxytropidoceras ammonite. 

 

B.2). The best Oxytropidoceras of the bunch. Its got an interesting feature that I am curious about. There seem to be some fragments of the original shell still attached in a couple of locations. These "shell fragments" have reddish orange splotches on a white base and have a distinct texture to them (I'm not sure if porous is the right word). I wonder if the red coloration is just staining or if they could be indicative of the shells original coloration. When I first noticed them I immediately thought of the red striped shells of modern nautiluses... but I am probably getting ahead of myself  .

 

C). An assortment of bivalves and Tylostoma snail. The two smallest clams appear to be Protocardia texana while the scallop is, I assume, Neithea. The largest clam is smooth and difficult for me to ID.

 

 

Denton Clay

 

Took a trip to a construction site. Didn't find anything and then got my leg cut on a rusty post. Got a tetanus booster and no lockjaw thankfully. 0/10 would not come back!

 

 

Pawpaw

 

I've been poking around a couple of construction sites located on the Pawpaw formation west of Ft. Worth. They've both been decently productive, though I wish I could've had more time to really look through them thoroughly. It's a really interesting layer with some notable dinosaur finds and shares some visual similarities with the Woodbine in my opinion. The sites I went to cut through I variety of levels in the Earth. I think they are all still within the Pawpaw, but I am honestly not sure. In a more elevated cut, I found the specimens shown in (A). I was super excited when I pulled my first Coenholectypus only to realize that it was very poorly preserved and covered in lots of matrix. I tried some vinegar on it which cleaned it a bit, but the way it's shattered and degraded on the other side makes me think this is as far as I'll go with it. In a lower layer, I found some really interesting fragments of purple ammonites and a bivalve (B). I tried hard to find something complete, but the best I could come away with was the tiny purple heteromorph I added additional pics of. I think the sites needs some rain as many of the fossils were covered in dust and hard to spot. Definitely places I will check out again when I'm back home. Lastly, I decided to include an updated pic of the micro Engonoceras that is seen in my pfp (C). I only just recently acquired paraloid b72 and have been enjoying it immensely. After applying some to my micro ammonite, it has obtained that beautiful "wet" look that really brings out its color and details. I've got some older pyrite ammonite encased in paraffin wax that I may try replacing with b72. I have a feeling they will look much better.

 

A). Bivalve and damaged Coenholectypus urchin.

 

B). Purple fragments of typical ammonites, heteromorphs, and a bivalve. A complete ammonite of this nature still eludes me despite my efforts.

 

C). My Engonoceras with a fresh coat of b72.

 

 

Eagle Ford

 

Despite the fact that I've been actively fossil hunting for about a year, my experience with the Eagle Ford is focused mostly on only a couple of brief visits to Post Oak Creek. I decided that now was a good time to finally jump in and try to figure this famous formation out. I hit up a few spots at a local creek with huge exposures of bluish shale. Despite the urban sprawl immediately surrounding the area, the tranquility of the creek made me feel like I was out alone deep in the wilderness. There was plenty of foliage and animals to populate it. Something about the place made me wonder if I had somehow traveled back in time. I was quick to get to work, scanning the shale and splitting open some slabs. The matrix was loaded with tons of fragile fish parts. Every slab contained a smattering of scales (I think) and other miscellaneous fish parts. Most of the small things were so delicate they would poof away when exposed to the air. The bigger things were a bit stronger and I was thankfully able to stabilize them before they were mostly destroyed. Early on, I got lucky with a beautiful little Enchodus jaw (A). I believe it's a piece of the lower one. To go with it I always came across a couple of jaw sections with larger fangs (B). Unfortunately, the tips of them immediately popped off and disappeared into the ether before I could preserve them. One slab surprised me with a broken shark tooth that I assume is Cretoxyrhina mantelli (C). It was the only shark tooth I came across that day, but it gives me hope for future expeditions. Of the thousands of fish scales I found, I decided to try and preserve a larger one (D). These guys were very fragile so I'm happy he made it out mostly in one piece. Once again, a slab surprised me... this time with a tiny ammonite, something I don't usually associate with the Eagle Ford (E). And to round off the day, I noticed some protrusions jutting out of the shaly bank. When removing them, I noticed they were rounded orbs containing a concentration of fish parts. I assume that these are coprolites. I don't know much about these sorts of ichnofossils so please inform me if I'm wrong. If they are coprolites, are they from a fish or a reptile and how can you tell? 

 

A). Lower Enchodus jaw?

 

B). Some Enchodus fangs and jaws. Tips broke off when revealed. These guys are both consolidated in b72 and were originally in multiple pieces. Reattaching the fangs was some tedious work.

 

C). Cretoxyrhina mantelli?

 

D). Fish scale preserved in b72.

 

E). A tiny ammonite in the shale

 

F). A crappy ending with some suspected coprolites.

 

 

In Conclusion

 

I had a nice summer break with plenty of time spent exploring the world of fossils surrounding where I grew up. It was a lot to take in, but I truly learned a great deal about the oceans that once swept over North Texas. The diversity of marine creatures is astonishing and it impresses me every time I split open that next slab of shale. With the school year starting up again, I am moving back to Austin. It's been a hot second since I've traveled to my usual Ozan spots and I am excited to get back into business. I'll take the sudden burst of rain today as a sign of good things to come. I can't help but think of all the freshly revealed marine fauna that have finally gotten the chance to take their first gulp of water in roughly 80 million years.

 

Edited August 23, 2022 by EPIKLULSXDDDDD

[JamieLynn]

Great report and Beautiful Engonoceras!  The smooth Bivalve from the Goodland is probably Cyprimeria. 

[Jared C]

Nice report! C. mantelli indeed

[GPayton]

Awesome trip report! My recent hunt with @Jared C in the Eagle Ford has made me much more interested in the formation than I was previously, when my only experience with it was a single trip to Post Oak Creek. I had no idea there were so many tiny pieces of fish scales and fish bone scattered throughout the shale until I saw them with my own eyes. It's crazy to think how many different individual fish lived and died in that spot over the years to produce that amount of detritus.

I have to say I'm jealous of that Cretoxyrhina! That has been my bucket list shark tooth find ever since I started fossil hunting. Now that I know where they can be found hopefully I'll find one as nice as yours. 

[DPS Ammonite]

C). An assortment of bivalves and Tylostoma snail. The two smallest clams appear to be Protocardia texana while the scallop is, I assume, Neithea. Thelargest clam is smooth and difficult for me to ID.

 

Large clam is Cyprimeria texana.

 

 

https://samnoblemuseum.ou.edu/common-fossils-of-oklahoma/gallery/cretaceous-fossil-gallery/cretaceous-bivalves-gallery/

 

[Bill Hoddson]

Wish I'd read this earlier today. I'm in Colleyville for a couple of days, and really wanted to look for Texas fossils  (I live in Michigan).  Only place I could find that wasn't too flooded was the Haslet Community Park.  Not much to be seen, but I did find one piece of limestone that looks to have marine worm trails. 

[Mikrogeophagus]

@Bill Hoddson PM'd