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This past Sunday I had the opportunity to join in a Dallas Paleo Society sponsored trip to the Ash Grove quarry in Midlothian, Texas. As with other quarries in this area, they are mining the carbonates of the Austin Group and often expose the Atco Fm. (Upper Cretaceous / Coniacian aged) near the base of the operations. In this case, the fossiliferous rock was found in various piles that had been moved aside during their work and usually can be identified by its grey color, speckled with black bits (the black bits either being fossils or phosphatic "pebbles"). Thanks go out to DPS for organizing this and to the Ash Grove quarry for allowing us in. Due to recent rains inundating an area of the quarry containing previously quarried material, we went to a very new part of the operations, where the sought after rock had just been dug up in the last week or so. Unfortunately, fossil hunting in this case greatly benefits from the rock having had a chance to weather so fresh stuff was not necessarily ideal, but the weather was fantastic, so that was good. The Atco is a marine deposit, part of the large inland waterway that cut north/south-ish across North America during much of the Cretaceous. It is a lag deposit , although the exact details of its deposition are the source of much debate. For most of the collectors on this trip, sharks teeth are the primary target, but there are other fossils to be found in the rock. First off, a couple of pictures of the group (there were about 50 participants) getting organized, heading down into the quarry and out collecting. A picture of the rock we were primarily searching for: Here is what I found. The last quarry trip in this area I was on, I came away with well over 100 small, but nice, teeth. This time was quite different, I probably only have a half dozen complete teeth, but a couple of pretty nice ones, so I was OK with that. This one looked really nice when I found it in the rock. The color was fantastic, a nice brown (almost all the teeth here are black), a little over an inch long blade (most teeth here are quite small), and very sharp edges still present. I cleaned it up a bit when I returned home and put a scale on it (increments are CM's). Unfortunately the root on this Cretoxyrhina mantelli is a little punky I think due to pyrite or some other diagenetic change. During cleaning a nice little tooth showed up just underneath (see third picture below) that looks like a little C. mantelli or a small Scapanorhynchus raphiodon posterior The other nice find of the day for me was a Ptychodus atcoensis, my best and largest Ptychcodus by far (I don't see these a lot in my collecting) and a new species for me. I neglected to take a picture that showed the whole rock it was in, about a grapefruit sized chunk of limestone but here is a close up of what was peaking out. When I returned home, I put my air scribe to work to see if it was complete or not, luckily it was and is in great condition. I have opted to leave it in the matrix for now and have trimmed down the rock to a more reasonable size. Lastly here are a few of the other fossils I picked up. A couple of bivalves (probably Ostrea for the small one on the left and Lopha for the larger) and then a chunk of what would have been a large Inoceramus which are quite common in this material. The fourth picture is wood I am told (I'm not a plant guy) which also was quite common in the the rock. That is all for now, thanks for taking a look. Mike

Well, you have probably already seen a few posts about the Dallas Paleontological Society's field trip to Ash Grove Quarry in Midlothian Texas. And Here's ANOTHER ONE! As it turns out, quite a few of us went on the same field trip but DIDN'T REALIZE WE WERE ALL ON THE SAME FIELD TRIP. That's what happens when you are mostly online friends and havn't actually met in real life! That and there were 50 people on the field trip....but it's a big quarry! Sorry I missed connecting in real life with @EPIKLULSXDDDDD, @PaleoPastels and @ClearLake! This actually was my first field trip with DPS and first time to this quarry so I wasn't very sure how things would play out, but we had a beautiful mostly cloudy day with a very nice breeze. As many of you know...quarrys in Texas can be brutal. We've been having surprisingly rainy and coolish weather, so it truly was a great day for hunting. Nice big rain the night before but not super muddy. Driving into the Quarry: I told you, there were a BUNCH of us The guy leading the trip, Francisco was really nice, made sure we were all geared up in our very very fashionable vests. He led us down to the bottom of the quarry where they had just placed a big pile of the strata we were looking for, so we didn't have to wander very far to find the right geology. Roger Farish, the DPS trip leader showed us what we were looking for...greyish rocks with lots of phosphate nodules. Most of the fossils are phosphatized, so the black was somewhat easy to see against the dryer grey, but in areas where it was still wet....that black was a bit tricky to see against the background. My first nice find was a good size Scapanorhynchus (goblin shark) about 3/4 inch long. And then a bit later in some of the pools of water, a lovely vertebra, also 3/4 inchish And there were some very nice big spiders. Don't worry. They were friendly. But.....what made my day, my month, my year was the next find. I found a Plesiosaur tooth. Yep. It was just sitting all nice and pretty on top of a small bank of mud and rocks off to the side, just sitting there waiting for me. It's kinda scrappy, but I don't care. I love it. I literally was shaking when I took it over to Roger F for confirmation it was indeed what I thought it was. So thank you Mother Nature! Here's some cleaned up and better pictures. It is one inch long So after that, I was just happy to wander around, maybe find something else...kind of wanting a Ptychodus tooth but content if I didn't find one and lo and behold....I see a tiny edge sticking out of a big chunk of rock and thought that sure looks like a ptychodus. I chipped it out and yep, a nice, if slightly broken, Ptychodus atcoenses. Not quite as nice as the one @ClearLake found, but I'm pleased with it. So a 3 1/2 hour drive up, a few hours of hunting and then drive back home again turned out to be totally worth it and an epic day for me. I found a plesiosaur tooth!!!!