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For whatever reason, I used to completely dismiss the Austin chalk as a formation of any interest. I viewed it almost through the same lens that I view the Edwards formation, as if it was some barren uninteresting hinderance that gets in the way of cooler formations. Accidentally finding a large Parapuzosia ammonite in it once changed that a bit, but for the most part I still ignored it... Turns out I was just looking in the wrong places, and had very little understanding of its members. @LSCHNELLE recently explained a lot of it better to me, and so equipped with new knowledge I decided to try and discover a member of the Austin Chalk I've been wondering about for a while now, which I always falsely assumed was its own formation. I found myself deep in a Travis county creek, following very specific instructions I had read on an old thesis from the 80's I found online. To avoid being too long winded - nothing stood out to me as different in the geology, so I think that the vertebrate rich member I was seeking still eludes me. Yet, I wouldn't say I was skunked, because I found some very interesting invertebrates that even a simpleton like myself can appreciate My first find had me cheering and jumping, partly because of how just picture perfect the insitu was, but mostly because it was just an aesthetic looking echinoid I haven't seen before. Here it sat below, as I originally saw it: Fortunately, what's left in the matrix I believe is still in great detail. It's just on a smaller-than-it-looks exposed portion where the wear took a toll, as you will see at the end when I show more photos. For another hour and half beyond this, I was just sloshing my way through the water, very slowly, admiring the highly fossiliferous limestone as I went. Usually when I scout a new spot, it ends up being more exploring than actual hunting, and yesterday was no different. Close to my turn around spot, I for whatever reason took strong notice of inconspicuous looking pebble lying loose on its own. Picking it upon a whim, I was surprised to see it was another echinoid of the same type I found earlier, albeit in worse condition. Pictures all at the end. (update: I now know that these are cidarids - funny that on april fools day, I make two of my rarest invertebrate finds, back to back. Odds are I won't have a luckier day in the invertebrate field ever again) Walking back was a serene vibe with few fossils - I was distracted by the new greenery that's been blooming lately. When I got back to where I found the first echinoid, I decided to poke around a bit more, and was surprised to find two ammonites - one large (Mortoniceras?) which I removed, and a much smaller ammonite as well. Results below! No vertebrates but these were well worth it! @JamieLynn put together a phenomenal guide of the inverts by formation that we can find in our central texas stratas, but I wasn't able to find these echinoids in it. I'm aware they need prep, but if you know what they are already please chip in! Results below: Echinoid #1: Echinoid #2 - While it's in worse shape than even the first, I think the substantial attached matrix has protected a lot of it. We'll find out when it preps! Larger ammonite I removed - glue will come to the rescue here. I'm rather sure that the inner coils are preserved under that! Smaller ammonite below: This was just one day sandwiched into what is so far a very busy weekend for me on the paleo front - lots of exploring, and also some good work brewing on two interesting, older vertebrate finds. I'll update this post when i eventually manage to get these echinoids cleaned - the hard limestone they're in will be tough for hand tools - perhaps this is my signal to finally buy a scribe. (update: rest assured, I won't be tackling these echinoids with my rudimentary prep skills - It'll be done by a professional)

With the end of the semester approaching, school has picked up and I have been too busy to embark on many adventures. When my schedule finally cleared up one afternoon following a brief rain in Austin, I jumped at the opportunity to do a bit of exploring. One of my goals right now is to check out new parts of the creek I hunt on. Scanning through my list of potential spots, I decided to try and be the first one out to a very promising location. Like my previous hunts, this place ran through the Ozan formation, so my expectations were set on some nice Cretaceous specimens as well as the usual native artifacts that Central Texas is so famous for. After I parked and carefully scaled my way down to the water's edge, I was immediately met with several pairs of shoes and jackets. Thinking I had been beaten to the punch, I decided I might as well head down the stream and meet whoever it was to discuss the location and fossils in general. Thankfully, the trip was saved when they turned out to be a kind group of fishermen. After a brief chat, I carried on to get the hunt started. The mud was an absolute nightmare. I had never been up to my knees in it until then. Somehow, I managed to trudge my way through without getting one of my water shoes sucked away into a different dimension. When I finally reached the first gravel bar, I was instantly rewarded with the nicest Ptychodus tooth (E) I have found yet. Scattered around the bar were tons of flakes and a couple of larger worked pieces (G, I) that were unfamiliar to me. Before moving on, I also stumbled upon what would've been the largest point I'd ever found (H). Unfortunately, it was pretty banged up. The previous rain wasn't that big in terms of flooding, so I spent the most time scouring the gravel still under water as I reasoned that the stuff on dry land was less likely to have been moved around in the storm. It was during this moment that I found my first mosasaur vertebra of the day (A). This one was exciting to me as I personally thought it very much resembled the verts that famously come out of the NSR's Ozan formation. Within a couple feet of it I found another half piece of mosasaur vertebra (B). With the close association of these two bones, I went into a bit of a frenzy. Nothing else came up, but I knew that there was a massive exposure just up ahead so I hurried on. Along the way I ran into a fragment of the smallest point I've come across (F). At its size, I wonder if the original piece would've been a true arrowhead. Once I reached the main exposure, I immediately got to probing around. I came across two more pieces of bone that I believe are both belonging to mosasaurs (C, D). They have bony structures, but they are also pretty beat up and may have come from a different formation in comparison to the other two verts I collected. With the day winding down I picked up a nice big Exogyra ponderosa for my dad's friend as well as a couple of preforms. I tried to look around in the exposure for any hints of mosasaur, but that shale is extremely difficult to get through. All in all, it was a great success. I think I've found my new go-to spot! With the addition of potentially 4 new mosasaur verts, that's a 400% increase in my total mosi collection! P.S. Does anyone else get "Tetris Syndrome" after scanning gravel bars for way too long? For hours after the trip, I literally could not stop seeing gravel and chert flakes every time I closed my eyes. An overview of the finds: Closeups for ID: A: First mosasaur vert of the day. To me, it strongly resembles those found in the NSR's Ozan formation. This one was covered in a clay-like matrix. B: The second vert of the day. Seems to be broken in half and from the same formation as A. Appears to have pyritization on some parts of it. C: Third vert which I believe is mosasaur. This one is beat up and seems to be of differing material from A and B. Could it be from the Austin Chalk which is present farther up the creek? D: The last "vert" of the day. This one I am least confident about. It appears to have a bony texture, but is very worn and has a confusing shape. It seems closer to C than A or B, but it also feels very distinct in it of itself. What do you guys think? I suppose it could be something else entirely! E: A nicely preserved Ptychodus tooth. I'm thinking anonymous or mammillaris, but my ID skills are pretty lackluster. F: "True" arrowhead fragment? G: Strange artifact. The angle seems too wide to be a point. I think it's too thin to be an adze. Obviously missing a huge chunk from that fresh curved break. What do you guys think? H: Fragment of a large point I: Another strange fragment. I think it may be an adze since it's a bit more robust. Fresh break on one edge. Let me know if you want any more close-ups. Thanks for reading!

I found this rock in Austin, TX in Waller Creek next to an exposed outcrop of the Maastrichtian (Late Cretaceous) Austin Chalk. I’m wondering if it’s a mosasaur vertebra or humerus? Several mosasaurs have been found in creeks nearby, and the wavy pattern in the rock reminds me of fossilized bone. I’ve included three photos of the rock that I found in Austin, and a photo from Otero et al. (2016) of a Maastrichtian mosasaur right humerus (scale bar = 50 mm) that looks similar.

Can anybody ID what this is? I found this several years ago in the North Texas creeks. It has some spots on the top and broken shells mixed with it. Could that round dark spots be coral or bryozoans?

My family and I love to explore creeks on the weekends. We've found many fossilized oyster shells before, but this is by far the largest specimen to date.

My next door neighbor, Jim, was kind enough to take me to my cataract surgery today, and after I took him out to breakfast, we had a little time to kill before my follow up appointment. On a whim, I suggested an Austin Chalk creek stomp since current drought conditions wouldn't result in muddy shoes. It was a fortuitous move, as the creek outperformed expectations. The bedrock there is slow to erode, so I've rested the site for a few years. We got 2 nice Eutrephoceras nautiloids. The one that Jim is posing with below is now cut to a nice pedestaled display piece which I presented to him and his wife tonight. (And I kept one eye closed while running the rock saw...left eye surgery is tomorrow, so no more flying rock dust for a few weeks.)

I didn't even realized they found the Mosasaur at this Garland Duck Creek (creek, not a formation), but in the Austin Chalk formation. I live just two miles from location and walked on this creek several times. Creek is several miles long. This was a rare find. Here is the follow up video.

While visiting family member in Central Texas, I couldn't resist stopping by roadcut next to the Interstate 35. Road crews are adding lanes so they were cutting lots of shoulder next to the highway embankments. I'm finding Inoceramus and giant clams measuring about 3 to 4 feet across. I have also seen similar giant clams in the DFW Austin Chalk layer, but this one looks almost intact.

This is my best find to date and I would love your input and observations... I found this specimen in McKinney Texas (suburb north of Dallas) in late 2020. While my wife my was antique shopping, I went to a local housing development to look for fossils. To my surprise I found this beautiful tail fin in the Austin Chalk formation. It was in about a 300 lb boulder, but it was well worth the effort to salvage it. I have returned to the area to search for more sections, but after hours of searching I haven't found anything new. In the original boulder, I also found a suspected scale and a single vertebrae. I also have only a small part of the matching side. I have now cut down to pieces and would like to present them to you for your insights. I tried to picture them in different lights/contrasts for you. (the measuring stick is in inches, the only measure I had in the house)

Took a little trip out to West Texas last weekend. My parents have friends who have ranches out near Balmorhea (great to have friends with ranches...everyone should have friends who have ranches!). I knew the general area was one I had wanted to go hunting for echinoids in the Boracho Formation (some very special echinoids not found in my area). I did my research on Google maps and the Texas Geology website, hoping I could pinpoint the right roadcuts! The first one we stopped at (I thought was the right formation) turned out to be a different formation, but I found some cool little brachiopods that are different than any i have encountered before and a couple of echinoids (phymosomas) and that was all for that little roadcut. Checked out a few more in the area but didn't find anything. Definitely didn't find what I was looking for! So on to our weekend at the ranch. The owner said he know of a "beach" on the ranch where "sea shells" were found. I was really surprised because on the Geology map it is all Igneous and Quaternary - nothing at all that looked Cretaceous fossiliferous. So we went driving around the ranch to the spot and to my GREAT surprise, we found an outcrop of Austin Chalk! I don't know how, but it was there! I found inoceramus clam parts and some of the most beautifully colored Exogyra erraticostata! So that was a really special spot! ( @grandpa -another "fossil that shouldn't be there!"- but it was!) The final day we were to head home, I convinced my parents to drive 30 miles further West before we headed back east for home. I knew there were supposed to be some more outcrops of the Boracho accessible so we took a little side trip and happily I found the formation I was looking for! And I was rewarded with a most LOVELY little Anorthopygus texanus echinoid! I initially thought it was a Coenholectypus transpecoensis (which was mainly what I was hoping to find -which I did not find!) but was happy to discover it was a more rare Anorthopygus! My mom found a nicely presereved Wahitaster wenoensis, so that was great too. I also found a phymosoma, but it's pretty beat up. A small section of a nautiloid and a nice bivalve which I think is a Lima wacoensis quadrangularis rounded out my day. So it was a good haul to West Texa! My best finds from Boracho /San Martine formation Anorthopygus texanus - 25 mm : Washitaster wenoensis 25 mm a not so great Phymosoma 1 1/2 inches Lima wacoensis quadragularis 1 inch From the Austin Chalk Formation on the ranch: Exogyra erraticostata 3 inches From the first roadcut which was Buda formation Kingena (Waconella) sp? what's odd about them is this "dip in the lip" so I am not sure what species it is (it is for sure Cretaceous Kingena/ Waconella and not a Pennsylvanian Composita which it very much looks like -we had a nice long post on that!) A few pics of some of the critters on the ranch: Auadad (not native, but gone native) Javelina mama and baby! A mule deer wild turkeys

I was driving north on Interstate 35 near Waxahachie, Texas this afternoon. Saw pile of rock debris that were up 60 feet high near the Interstate 35 service road. I couldn't resist passing by, so I parked near the service road and walked around the debris for any fossils. Well, most of the fossils I found are small to large Inceramous clams. Not too much spectacular, but the clam attached to the matrix were near complete. Some of these clams have pyrite rust stains on them. Formation is Austin Chalk (upper Cretaceous).

I found this piece of rock with strange shape in the rock quarry nearby Interstate 35 between Temple and Waco, Texas. I did't see much other fossils other than this piece. Wonder what this is? Formation is on Austin Chalk.

I'm trying to identify a fossil I found inside a chunk of Austin Chalk or in the "Fau" Cretaceous layer in collin county. I believe it might be some sort of coral. I am leaving it for now hoping to determine what it is before trying to fully extract it. Might not ever try to remove it. Any ideas or opinions? would be interesting to see what others think. It appears to have a foot then a thin shell like skin with a scalloped edge at the base growing horizontally from the "foot" like a shute or pod. Found in creek collin county North of Dallas Texas

Is this called ammonite or another name for these specie? I found these at Dallas Trinity river grey clay / shale layer. I think these are upper cretaceous Austin chalk formation.