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Found 39 results

  1. Silly Season

    It’s that time of year... Ancient Marine Fossils Unearthed in Plano, nbcdfw.com
  2. Ive recently started donating some important Mosasaur finds of mine to Mike Poclyn at SMU for his continuious research of Mosasaurs. I donated Russellsaurine premaxilla from the Austin Chalk formation in a creek in Dallas County and then a rare Halisaurine dentary which is the only Halisaruine skull piece Mike has ever seen from the North Sulphur river. Mike is truly a awesome guy and I am looking forward to continue working with him in contributing rare finds for research.
  3. Micro teeth? Not sure

    Found in Atco formation in Texas, Coniacian age. Looking in my Welton Farish book and I can’t find anything similar. Maybe spines of some sort? Kind of looks like teeth and kind of not. Lost on this one. Scale is in mm.
  4. Found this digging through my micro gravel. It comes from the late Cretaceous, bottom of the Austin chalk, top of Eagle ford, Atco formation area. It is 3mm in length and I would say 1ish in width. Internal mold of something, crustacean maybe? Really not sure.
  5. Edwards Check Dams

    A few weeks ago my mother, Stella (dog), and I went to a old-reliable heteromorph site in the Atco. After I dragged all my equipment to the part of the site that I was going to work, she went walking with Stella to look at some of the check-dams full of brought in Edwards limestone, chicken wire bags full of the brought in matrix put in the ditches for sediment control. In 2017 while we were at the same Atco site she was looking at a dumped pile of the Edwards and found a rare cidarid (see thread here) that compares well with Temnocidaris (Stereocidaris) hudspethensis. The sight of seeing that bizarre looking fossil just laying on the ground was quite a shock for both of us and motivation to hunt the dams more, and since then she has been casually looking over every check-dam hoping for another one. But because this Atco site is also rich in heteromorphs, I tend to focus all my attention on the chalk and neglect the Edwards dams, in these cases to my slight ire but also amazement at what she found with Stella. She did it again on the 9th, and found another cidarid that appears to be the same species as the last one from 2017, though from a different dam. I was at my Atco pile when she came over and showed it to me, completely blowing away all my finds in a very welcome way. The brought in Edwards is early upper Albian in age (about 107.6 mybp) and is a very fossiliferous crystalline limestone jammed packed with rudists and Chondrodonta sp. as well as the occasional gastropod. It makes for quite the sensory overload when trying to look for other things amongst the fossiliferous morass. The limestone is also interspersed with somewhat softer red sandstone that infills crevices in the much harder limestone and is more quickly weathered away in older exposures. I have tried so-far unsuccessfully to isolate the quarry from which the matrix originated to ask them permission to get a chance at the fossils before they are dumped in bags and hauled tens of miles to sites, damaging them. The problem is that there are multiple quarries in the nearest counties that expose the Edwards, namely Hood and Johnson counties. I have seen this matrix at sites all over North Texas, but I don't know if all that matrix is from the same quarry as the matrix from my Atco site since the Edwards is heavily quarried for fill all over the state. For now we are left to dig though the jumbled, knocked around bagged matrix, but even so the limestone is extremely hard so the fossils are not usually completely destroyed. And the site is big with lots of busted open bags. This latest cidarid is in about the same condition as the first, that being not so great but not so bad. Both specimens are missing most of their adoral sides and their apical plates are gone, leaving their circular apical scars. But they are still quite nice and intricately detailed, and also preserve some of their big mamelon tubercles, with the first specimen preserving 2 and the latest preserving 5, though there could be more under the globs of matrix stuck to them. This latest is also bigger. The first had a diameter of 52 mm at the ambitus and a preserved height of 37 mm, while the latest is 59 mm at the ambitus and 45 mm in height, though keep in mind that since they are both missing most of their adoral sides they would have had more height in life. The apical scar on the first specimen is 19 mm in diameter and on the second is 21 mm, with the crushed calcite fragments of the apical plates seen in the cavities left behind on both. I really didn't expect her to find another specimen of this rarity again, but apparently this matrix is a honey hole brought in by the truck load, making this site two honey holes in two epochs. Then on Wednesday I went by the same check dam from which this latest cidarid came and found what really appears to be a belemnite, but that is for another topic in the ID forum. Hopefully I can post that find soon. Since new Atco exposure at the site has temporarily slowed down I have an excuse to take a good hard look at the Edwards dams tomorrow afternoon. If we find anymore from the dams I will post it to this thread, so hope to see more In the mean time, here are the pictures of the echinoids, the check dam from which this latest specimen came, and a nifty Chondrodonta sp. she found in said dam. I welcome any other finds that anyone has found in the Edwards or its equivalents and any tips on how to prep limestone as hard as crystalized concrete. Also, sorry for the picture quality. My Nikon decided to die a few months ago for some reason and I have yet to get it fixed, so if anyone knows a camera repair shop that fixes Nikons in the DFW area, I am all ears. *Pictures incoming, computer acting up*
  6. I found this Phlycticrioceras trinodosum heteromorph specimen in June of 2018 whilst hunting the middle/upper Coniacian Atco formation. It is the largest fragment of this species that I am aware of, having a whorl height of 51 mm as opposed to 47 mm of the largest fragment I've seen published. This genus is a bigger, rarer, and (mostly) younger cousin of Allocrioceras. I sent pictures of it to Keith Minor and he pointed out that there was also an echinoid sticking out of the specimen, something which I had totally missed! With much of the echinoid still stuck in the living chamber it is hard to get a definitive ID. But because it has such a shallow anterior ambulacra, which gives the anterior end a more smooth rather than definitive heart shape, he ruled out both Mecaster texanus and batensis. He suggested Micraster since the site has a strong European component in both the bivalve and ammonite faunas, and because the periproct side has the right shape. From finding other, although not as well preserved specimens that show similar morphology he appears to be right. I have yet to confirm this ID with Andrew Smith, but either way I think the piece is worth showing. And reading this thread got me thinking about how this could have happened and what effect it could have had on the echinoid's preservation. My thought is that because irregular echinoids lived and today still live most of their lives burrowing in the sediment it is unlikely that it would have crawled into the living chamber, but instead that it was blown into it post-mortem via currents that had dredged it out of the sediment. I already know that this site was a high energy environment from my other finds here so this seems the most likely possibility to me. But because of the fact there is still at least one spine still attached to the specimen it could not have been swept up from the sediment too long after death or all of its hairlike spines would have blown away. I do, however, find it interesting that it is positioned anterior first with its posterior towards the aperture, the position I would expect to see it in if it had indeed crawled into the shell. The specimen is also the best preserved echinoid from this site so far. Despite the ammonites being generally well preserved and not too crushed, most of the echinoids that I have from the site are terribly crushed, flakey, and often infested with rotting pyrite. I think being encapsulated in the chamber very much reduced those effects. Even though the ammonite and the echinoid are a bit crushed, the echinoid would have probably been worse off otherwise. The heteromorph fragment length is 70 mm and the whorl breadth, being a bit crushed, is 13 mm. I would think that this specimen, with its open planispiral coiling, would would have been at least over a foot in diameter when complete. It is the robust (female) morph of the species with a rib index of 5½. For comparison in Fig. 1 I pictured it with my most complete P. trinodosum specimen. From the part of the echinoid that is exposed I can measure 25 mm in length, 25 in width, and a thickness of 8 mm. I have also found abundant yet scattered fish remains at the site, so perhaps one day an ammonite-fish will come my way. But until then, anyone else got ammonite-echinoids to show? Fig. 1. Fig. 2.
  7. Crab carapace?

    Unknown fossil. Found just below a tidal deposit and above a deep water lime deposit. In this layer there are a lot of good sized amonites, and a smattering of pelecypods and scallops and oysters and protocardia and urchins that become much more common just up the rock sequence. Just a bit deeper are fairly common trace fossils of burrowing shells.
  8. Bone like fossil with cuts

    Found this bone like fossil while exploring the creeks in far north Dallas. This area I believe is part of the Austin chalk formation. whats odd is the two small cuts and what looks like worms fossilized on the underside. It’s hard like rock.
  9. Giant Inoceramus clam?

    I am a bit excited and probably rash in my thinking on this. I’m sitting in a creek and I believe I’m sitting on the remains of the largest clam I have ever seen. I’m having a hard time processing it and don’t know how to confirm my suspicions of how large this beast is. Would anyone even be interested in checking this out? Here are some pics. If I am correct this clam goes at least from a foot to the right of the black thing to at least 3 feet to the left of my hammer. This is is a layer of shell across the top of it. More shell Sounds like I may have an overactive imaginations, but I’m not sure how to explain it otherwise. What do you guys think?
  10. Tiny Aptychus or Bivalve Steinkern?

    Yesterday I hunted an Upper Santonian Austin Chalk site in Ellis county between downpours of rain. This was my first time at the site. I was looking around a pile of rocks with some boulders mixed in and found this on one of the boulders. It is tiny, whatever it is, about 1 cm wide. Now I must admit that I am more familiar with the fauna of the Upper Coniacian Austin Chalk but to me this looks more like half of the aptychus of an ammonite than a bivalve. Since an aptychus was made of calcite I believe that it would be preserved in chalk, though the actual fossilized material is gone and this is just the steinkern of what ever it was. Here is the best picture that I have of it. Sorry that the quality is poor. I took it while I was at the site and I can’t get a better picture right now. Hopfully this will be sufficient.
  11. Dust Masks

    So far the only prep tools that I have are different types of picks. Because of this there isn’t that much chalk dust being put into the air at one time. I currently wear surgical masks which are less restrictive than other dust masks but they seem to be ok for what I am doing. If at some point in the future I start using tools that generate more dust, such as air scribes, would these kinds of masks work or would I need more restrictive ones? What do you use? Thank you all very much for the help that I have received. I am just beginning to prep fossils and I am trying to learn as much as I can.
  12. I have a Tridenticeras peramplum ammonite steinkern from the Austin Chalk that has part of it incrusted with algae/moss from sitting in a small creek where I found it. What would be recommended to clean moss off of chalk fossils, not just ammonites? What ever the method that is recommended I would first try it out on a fossil-less chunk of chalk to make sure that the process wouldn’t be detrimental to the matrix. I also don’t want to scratch the fossil by scrubbing it with something overly abrasive since the matrix weakens when wet. I usually use a soft bristled toothbrush for cleaning dirt off of specimens. Would that enough? Thanks in advance!
  13. Austin Chalk fossil

    I got off work early last Friday and had about 90 minutes to kill before picking my daughter up from school. So I decided to see if I could find anything in a local nature preserve with Rowlett Creek running through it, which consists of the Austin Chalk formation. There were lots of Inoceramus clam shell fragments. One fragment that I found was over 10 inches wide, but still only a tiny fragment of what must have been an enormous clam. As I was exploring I came across this rock which I though was unusual. When I first saw it I thought someone had gotten might bored and sat there hacking away at the rock to make all the hash marks, but upon closer inspection I realized the hash marks went more than surface deep. It has to be a fossil of some kind, but I’ve never seen anything like it. The only thing I can think of is maybe it is some type of a cast of a pile of shells that were together. The marks go about 4 mm or so into the Chalk so maybe it is what is left of clam fossils and the rest of the fossils have eroded away. Do any of you know what kind of fossil this is?
  14. Cracking Open Chalk Chunks

    Right now I am almost exclusively hunting in the Austin Chalk Formation. I am curious what tools I would need to crack open chunks of it to look for fossils. What kind of chisel and hammer would be recommended? Is that all that would be needed? The matrix that I am working with is medium hardness.
  15. I had about an hour and a half to go hunt for fossils today. Someone had been asking to go hunting with me and today was the only time I’d be free to go until after New Years. There has been a lot of construction on highway 75 in McKinney, TX and they took a lot of the rock dug up during construction and dumped it in a field by 75 just north of the county courthouse on the east side of 75. I had seen the piles of construction rock several times and wanted to check out what fossils might be in the McKinney underground. I doubted there would be much of interest, because it’s the Austin Chalk and I live near and on it and there are very few fossils in the chalk that are preserved well and they are mostly chalk clam casts from what I’ve seen. The other things I’ve seen where the actual clam was preserved mostly had fragments of the shell and nothing whole. But I was hoping if it had been dug up maybe it would be preserved better. No such luck, but it was interesting to see. Here are a few pics I took. There were lots of clam remnants, some quite large. Someone can correct me if I’m wrong, but I believe they are Inoceramus clams. This was the dump site. It had been there a while. This is a good example of the colors you will see. The brown to taupe color (on the right) I believe to be the outer layer of the original shell. The yellow and rust color (on the left) is where the original shell pulled away from where the clam was when the chalk split. This slab is about 2 feet long and about as much wide at the top. You can see numerous layers with clam spanning the whole width and length. Sometimes multiple clams were overlaying one another. I put my key fob on this for scale. I think there were 2 clams here. One on top left and another that is only a fragment, but still looks to have been well over 12 inches wide. There were a few specimens where the whole layer of the outer shell was preserved fairly well. This is one of them. I put my hand in the pic for approximate size. I think my hand is about 8 inches long. So this clam was about 5 inches wide. I left my heavy duty hammer and chisel in the car. I tried breaking the rock so I could carry it out, but I didn’t manage to break it. Heres another one of similar size. This one must have been quite large by my estimation, but nowhere near as big as Inoceramus clams get. I read in Wikipedia that one over 3 meters had been found. This could easily have been 20 inches across or more. Most all of the slabs were 2 feet plus. The chalk often split or broke easily, but it was hard to pull apart in the plane of the clam shell in one piece. The fossils were quite fragile and not of the best quality, but they were cool to see. It was an interesting visit, but I wasn’t able to bring much home sad to say.
  16. Ammonite aptychus?

    I recently hunted in the Austin Chalk (in Austin) for the first time and am unfamiliar with the fossils there. I posted another ID question for something I found and the ammonite suggestion sent me on a research mission. Now I'm wondering if something else we found was actually ammonite aptychus instead of the bivalves I thought they were. Most of the ones I saw online were MUCH smaller, but looked very similar. What do you think? I didn't bring this home so can't get any other pictures/measurements. I really need to pack a ruler in our gear! I have pretty average sized hands.
  17. Cretaceous bivalve/mollusk?

    Founds this in Austin, in the Austin Chalk. It's 10 cm across. Any ideas what it is?
  18. Unusual tooth

    Good afternoon, I found this is Travis county after a recent flood. I'm in the creek often and have never seen this. Hoping y'all can ID, thanks IMG_20170809_170048.jpg
  19. I'm still breaking down shale chunks that I brought home from the Martin Marietta quarry in Midlothian, TX. Site covers the Atco contact between the Eagle Ford shale & the Austin Chalk formations. Lots of micro stuff in there. Here are my latest tiny finds. Scale in all photos is in millimeters. Pycnodont fish tooth. Thanks to Mike Everhart for the ID! Ptychotrygon sp. ray tooth #1 Ptychotrygon sp. ray tooth #2 Vertebra, I suspect fish of some type or other, That's the offbeat stuff. Most of the rest is all shark teeth in varying condition. Haven't gotten photos of those yet, too big for my micro camera.
  20. Echinoid in situ

    From the album Grayson Co. Texas finds

    Echinoid in situ. Found in the north northeast corner of Grayson county Texas in Choctaw creek. Washita group possibly Weno?
  21. Post Oak Creek Microtooth ID help

    I brought home a bucket of gravel from Post oak creek in Sherman Tx. to sift through, and came across this beauty. The size is approx. 1.5 to 2 mm.
  22. April 9 was my birthday, and what a coincidence... it also happened to be a day when Dallas Paleo Society had a field trip scheduled into the Martin Marietta quarry down in Midlothian, TX... and I got on the list. The first "find" of the day was when Polly, our trip leader, presented me with a birthday cupcake. After signing our release forms, the DPS crew was led into the quarry. We were taken to an area where they had just dug up some fresh rock. Everyone scattered about the area, and soon the "clink.. clink..." of rock hammers on shale was heard everywhere. (Just for the record, the site is in the basal Atco formation of the Austin Chalk.) I wasn't doing so well. Nothing seemed to be turning up in the older section that I had decided to check out, so I wandered back over into the new area with everyone else. Nothing much happened in the first few minutes of surface collecting, then I saw THIS... My first ever fossil fish tail! Probably no chance of ever getting a genus or species ID on this. Still, it's Cretaceous Fish, and that's good enough for me. I was lucky that the slab had split right there, so both the tail & counterslab were right next to each other. I sat down and started going through the other rock in that area, and found this, too: Might be part of the same fish, but I think I'll have to do a bit of prep work on it to be able to tell if it's head, body chunk, or what. I have the fish material stored in a temporary jacket til I get time to lay some Butvar-76 on it. (Continued... )
  23. ammonite or clam fragment?

    Hi Y'all, I'm new to fossil hunting but have been having great fun tracking down fossil areas in a creek bed from a 1924 paper I found online. I don't know what excites me more, finding fossils or finding the exact locations the author discussed, right down to the sketched lemonite stains on joint faults and rusted nodule of marcasite! In any case, at one of these spots — Upper Cretaceous/upper Austin Chalk layers, Near Selma, TX — I found some well-weathered Exogyra laeviuscula as expected and also this fossil fragment in the chalk rubble at the base of the outcrop. It kinda looks like a ammonite fragment or clam fragment, but it's hard to tell. Not much was showing when I found it and I've been using it as a bit of practice for cleaning techniques, so a bit more is visible now. I've soaked it in vinegar, then sodium bicarbonate, then water, used picks on it, then repeat repeat repeat. It's not a showpiece but I need the practice... Anyway, wondering if anyone knows what kind of fragment it is? I should also note that after I was able to scrape most of the chalk off, which was fairly easy, there is a much harder caramel color stone or mineral beneath in between the fossil stripes that really resists removal.
  24. My finds so far from the Dallas Paleo Society field trip to the Martin Marietta quarry. ( I still have a lot of matrix to break down.) IDs are based on my comparing the teeth to the best of my ability with Welton & Farish's book on fossil sharks & rays of Cretaceous Texas. A shark tooth peeking out of the matrix. I managed to fumble-finger while trying to extract it in the field, and lost the side cusp. An overview of the teeth. Top row, L to R: Unknown, Cretodus, Scapanorynchus, unknown, Cretolamna. Bottow row, L to R: Carcharias? symphyseal tooth, broken Scapanorynchus crown, rest unknown. (Continued in next post)