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Found 171 results

  1. Petrified Wood - Nebraska 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Petrified Wood SITE LOCATION: West Point, Cumings, Co., Nebraska, USA TIME PERIOD: Late Cretaceous (75-100 Million Years Ago) Data: Lake Superior Agate - Petrified wood (from the Greek root petro meaning "rock" or "stone"; literally "wood turned into stone") is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization. All the organic materials have been replaced with minerals (mostly a silicate, such as quartz), while retaining the original structure of the stem tissue. Unlike other types of fossils which are typically impressions or compressions, petrified wood is a three-dimensional representation of the original organic material. The petrifaction process occurs underground, when wood becomes buried under sediment or volcanic ash and is initially preserved due to a lack of oxygen which inhibits aerobic decomposition. Mineral-laden water flowing through the covering material deposits minerals in the plant's cells; as the plant's lignin and cellulose decay, a stone mold forms in its place. The organic matter needs to become petrified before it decomposes completely. A forest where such material has petrified becomes known as a petrified forest. Kingdom: Plantae
  2. Petrified Wood - Nebraska 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Petrified Wood SITE LOCATION: West Point, Cumings, Co., Nebraska, USA TIME PERIOD: Late Cretaceous (75-100 Million Years Ago) Data: Lake Superior Agate - Petrified wood (from the Greek root petro meaning "rock" or "stone"; literally "wood turned into stone") is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization. All the organic materials have been replaced with minerals (mostly a silicate, such as quartz), while retaining the original structure of the stem tissue. Unlike other types of fossils which are typically impressions or compressions, petrified wood is a three-dimensional representation of the original organic material. The petrifaction process occurs underground, when wood becomes buried under sediment or volcanic ash and is initially preserved due to a lack of oxygen which inhibits aerobic decomposition. Mineral-laden water flowing through the covering material deposits minerals in the plant's cells; as the plant's lignin and cellulose decay, a stone mold forms in its place. The organic matter needs to become petrified before it decomposes completely. A forest where such material has petrified becomes known as a petrified forest. Kingdom: Plantae
  3. Petrified Wood - Nebraska 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Petrified Wood SITE LOCATION: West Point, Cumings, Co., Nebraska, USA TIME PERIOD: Late Cretaceous (75-100 Million Years Ago) Data: Lake Superior Agate - Petrified wood (from the Greek root petro meaning "rock" or "stone"; literally "wood turned into stone") is the name given to a special type of fossilized remains of terrestrial vegetation. It is the result of a tree or tree-like plants having completely transitioned to stone by the process of permineralization. All the organic materials have been replaced with minerals (mostly a silicate, such as quartz), while retaining the original structure of the stem tissue. Unlike other types of fossils which are typically impressions or compressions, petrified wood is a three-dimensional representation of the original organic material. The petrifaction process occurs underground, when wood becomes buried under sediment or volcanic ash and is initially preserved due to a lack of oxygen which inhibits aerobic decomposition. Mineral-laden water flowing through the covering material deposits minerals in the plant's cells; as the plant's lignin and cellulose decay, a stone mold forms in its place. The organic matter needs to become petrified before it decomposes completely. A forest where such material has petrified becomes known as a petrified forest. Kingdom: Plantae
  4. Paper just released that describes the dorsal vertebrae in detail of the titanosaur Dreadnoughtus schrani from Argentina that was described in 2014. If you ever wanted to know what the different areas of a dorsal vertebra were called this gives you more than you ever need. It also gives you relative position in the vertebral column. You will be tested on the pronunciation and spelling of these words Check the scale bar it's 50 cm (appox 20 inches) Complete dorsal vertebrae are very rare especially this well preserved. This discovery gives paleontologist an opportunity to use these specimens to compare against other taxons. It also gives them a better understanding of their position in the sketal structure. https://www.app.pan.pl/article/item/app003912017.html Osteology of the dorsal vertebrae of the giant titanosaurian sauropod dinosaur Dreadnoughtus schrani from the Late Cretaceous of Argentina Kristyn K. Voegele, Matthew C. Lamanna, and Kenneth J. Lacovara Acta Palaeontologica Polonica 62 (4), 2017: 667-681 doi:https://doi.org/10.4202/app.00391.2017 app62-Voegele_etal_SOM.pdfapp003912017.pdf Supplemental Images app003912017.pdf Dreadnoughtus 2014 paper https://www.nature.com/articles/srep06196
  5. Tiny once thought to be a Triceratops its actually a Torosaurus Paper says Tiny is the most complete Cretaceous dinosaur found in Colorado http://www.denverpost.com/2017/12/05/thornton-triceratops-torosaurus/ Current bone map provide by Joe Sertich curator Denver Museum of Nature and Science Press Release from Museum
  6. MOSASAUR JAW.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Mosasaur Jaw Oued Zem, Morocco TIME PERIOD: Late Cretaceous (73-95 Million Years Ago) First and most importantly, mosasaurs are not dinosaurs. Mosasaurs (from Latin Mosa meaning the 'Meuse river', and Greek sauros meaning 'lizard') are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. Mosasaurs probably evolved from an extinct group of aquatic lizards known as aigialosaurs in the Early Cretaceous. During the last 20 million years of the Cretaceous period (Turonian-Maastrichtian ages), with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators. They became extinct as a result of the K-Pg event at the end of the Cretaceous period, about 66 million years ago. Kingdom: Animalia Phylum: Chordata Class: Reptilia Order: Squamata Family: †Mosasauridae
  7. Fossil Mosasaur Teeth.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Fossil Mosasaur Teeth Khourigba, Morocco TIME PERIOD: Late Cretaceous (~70 Million Years ago) Data: First and most importantly, mosasaurs are not dinosaurs. Mosasaurs (from Latin Mosa meaning the 'Meuse river', and Greek sauros meaning 'lizard') are an extinct group of large marine reptiles. Their first fossil remains were discovered in a limestone quarry at Maastricht on the Meuse in 1764. Mosasaurs probably evolved from an extinct group of aquatic lizards known as aigialosaurs in the Early Cretaceous. During the last 20 million years of the Cretaceous period (Turonian-Maastrichtian ages), with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators. They became extinct as a result of the K-Pg event at the end of the Cretaceous period, about 66 million years ago. Kingdom: Animalia Phylum: Chordata Class: Reptilia Order: Squamata Family: †Mosasauridae
  8. In March of this year I found a heteromorphic ammonite that has had me curious ever since. So yesterday I finally sent an email about it to a local ammonite expert, Ron Morin, who is associated with the Dallas Paleontological Society. I had a correspondence with him in May of this year as it related to him identifying my Phlycticrioceras trinodosum heteromorphic ammonite which I recently added to 'Collections'. That's when I first talked to him. Then at the Dallas Paleontological Society's Fossil Mania event in October, I was talking to Roger Farish about my unidentified ammonite. He recommended that I contact him again for identification. Here is the email and the pictures that I sent him yesterday. I will post an update to this thread when he responds, which from my experience might be weeks. I have edited it to remove any slightly sensitive information like my name and more specific location information (I'm paranoid), as well as to fix any grammatical errors and to add relevant reference designations in between the < and > symbols: "Hello! I am Heteromorph, the one who contacted you to identify my Phlycticrioceras trinodosum specimen in May of this year, and I was wondering if you could help me identify another heteromorphic ammonite from the Upper Coniacian stage of the Austin Chalk. This specimen was found on March 23 of this year in a creek in Ellis county. It is, in fact, within half a mile of where I found the last specimen that I sent to you for identification. The stratigraphy of this area is the Atco member of the Austin Chalk, Prionocycloceras gabrielense zone. My problem is that even though it resembles P. trinodosum, there are differences that would make me reluctant to indenify it as such. To date, I have not found one like it. It is similar to P. trinodosum in that the whorl section is compressed, it has ventral tubercles, and it has an open planispiral shape. But it also has 3 key differences that make me think it is either a different species or it is very pathological. I list these below. First and foremost, the main difference is the lack of any ventrolateral tubercles, which are one of the defining characteristics of P. trinodosum. On both the specimen itself and its negative, it appears to be free of any ventrolateral tubercles. The only tubercles that I can see are the ventral tubercles which are something that P. trinodosum has as well. Second, the ribs are shaped differently than P. trinodosum. While P. trinodosum has rectiradiate ribs, this specimen has ribs which are rectiradiate until about half way up from the umbilicus, at which point it bends. Due to the fragmentary nature of this specimen, I have a hard time determining whether it bends abapically or adapically. Third, the ribs are more costate on this specimen than any of the twelve P. trinodosum specimens that I have found in the Austin Chalk. It has a rib index of 7, while the most costate specimen that I have found and know for sure is a P. trinodosum specimen only has a rib index of 5. While this is not unheard of for this species, with specimens of this species having rib indexes of up to 8 (Emerson et al. 1994), yet from my experience it is apparently very unusual for this part of the Austin Chalk. The closest thing that I have seen to my specimen is illustrated on Plate 11, fig 2 of Young, 1963 (as P. sp. cfr. douvillei), the similarity being the fact that they both have rib indexes of 7. After that, though, the similarity ends in that P. sp cfr. P. douvillei still has ventrolateral tubercles and rectiradiate ribs. I also found a very small P. trinodosum negative in the same creek just a few feet away. It has ventrolateral tubercles and a rib index of 4. The ribs are rectiradiate. A photo of it is not attached here. My specimen is 87mm long including its negative and has a whorl height of 34½mm. The oval whorl section is compressed like P. trinodosum. It is shown first in the attached photo DSCN5355. Aside from the specimen in question, for reference I have also attached photos of two P. trinodosum specimens that I have found. They are both from within 5 miles of the creek site, so they are on roughly the same stratigraphic level. What I am calling P1 is shown first in the attached photo DSCN5281 <F13> in comparison with the specimen in question. P1's negative is shown first in the attached photo DSCN5394 <22>. The positive is 69mm long when both pieces of it are measured together but 53mm when just measuring the largest piece. It has a whorl height of 31mm and a whorl breadth of 9mm. Rib index of 4. It was found within a quarter of a mile of the creek site. Because it is has just a slightly shorter whorl section to the specimen in question it is a good comparison piece. The specimen which I am calling P2 is shown in the attached photo DSCN5361 <F27>. It is only a negative but I am attaching a picture of it here because it is the specimen that I referenced earlier with a rib index of 5. It is 23mm long and has a whorl height of 15mm. It was found about 4-5 miles to the south-west of the creek site. For reference, here is a post I made about the P. trinodosum specimen that I sent you a picture of in May. I thank you very much for your help in advance. Sincerely, Heteromorph" I have given an alphanumerical designation to each picture for ease of reference. I guess it is probably kinda silly to have so many pictures that this is necessary. If this is stupid, than I extent my apologies to the Mods. I will patiently receive correction. Thank you to everyone in advance. F1 F2 F3 F4
  9. The Transylvanian area of Romania boasts a rich fossil record of dinosaurs, which lived on an island (Haţeg Island) during the very end of the Cretaceous. Many of these are dwarfed in body size or exhibit other unusual features thought to be linked to their insular habitat. One of the most common of these dinosaurs is the rhabdodontid ornithopod Zalmoxes. This paper takes a look at new specimens found at the Nălaț-Vad locality. A catalog of Zalmoxes (Dinosauria, Ornithopoda) specimens from the Upper Cretaceous Nălaț-Vad locality, Hațeg Basin, Romania. (American Museum novitates, no. 3884) Brusatte, Stephen.; Dumbravă, Mihai.; Vremir, Mátyás.; Csiki-Sava, Zoltán.; Totoianu, Radu.; Norell, Mark. http://digitallibrary.amnh.org/handle/2246/6781
  10. whose humerus

    went hunting in a small site that normally produces small crow shark teeth and enchodus teeth and pieces of turtle shell and found this bone. not sure what it belonged to.thanks
  11. Possible dinosaur remains found in Lithuania

    Dear Guys, I recently found two remains (serrated tooth and scale) of possible small dinosaurs in the Late Cretaceous erratics of South Lithuania, Eastern Europe. The tooth is about 1,2 cm length, scale is 4 mm length. If the remains belong to dinosaurs, which dinosaur fossils it could be? Any opinions are very welcome Best Regards Domas
  12. Chiropractor discovers BC's first dino skull. Looks like a Tyrannosaurid. Pretty good find while on holiday http://www.cbc.ca/amp/1.4158748
  13. Bone Fragment

    I literally joined the forum 5 minutes ago, and I am still learning about the technicalities of paleontology. So if I use terms or vocabulary in the wrong context please excuse me. I have recently acquired a bone fragment that was found in the Hell Creek Formation near Jordan Montana,and it is from the Late cretaceous period. This is all I currently know about this fossil. I need help identifying the species that this bone fragment is from. Thanks for the help !
  14. Sauropod tooth from Hungary

    A new paper is available that will shed new light on Late Cretaceous titanosauriform evolution in Laurasia: http://www.nature.com/articles/s41598-017-03602-2#Sec4 The titanosaur fauna from Late Cretaceous Europe has been well documented in the literature over the generations, but the discovery of a basal titanosauriform tooth in Santonian-age sediments in Hungary is important because it fills a gap in the fossil record of post-Cenomanian, pre-late Campanian European titanosauriforms and suggests that Late Cretaceous non-titanosaur somphospondylians may have been more widespread in Laurasia than previously thought because the discovery of sauropod remains from the Bissekty Formation of Uzbekistan shows that some latest Cretaceous European titanosaurs may have evolved from a central Asian ancestor.
  15. Late Cretaceous small tetrapods found in Lithuania

    Dear Guys, I made the pictures of possible big discovery in Late Cretaceous erratics of Lithuania. There are some frog bones in flints (ilium, urostyle, tibiofibula, scapula), snake pieces (tibiofibula like of Tetrapodophis! and one thin scale), and toothed birs upper and lower jaw fossils. If you could confirm these finds, it will be the first further my article in scientific magazine and I wish it will be successful. There will be some posts, please review the pictures and tell what do you think. At first, I will show you frog remains. Best Regards Domas The second part- snake remains.
  16. Zuul crurivastator David Evans of the ROM contributed in describing a new ankylosaur from northern Montana's Judith River Fornatikn. One of the most complete Ankylosaurs ever found ROM's release http://www.rom.on.ca/en/collections-research/research-community-projects/zuul http://blogs.discovermagazine.com/deadthings/2017/05/09/meet-zuul-crurivastator-i-aint-fraid-of-no-ankylosaur/#.WRJrc5BlDxA http://www.sciencemag.org/news/2017/05/demon-faced-dinosaur-named-after-ghostbusters-baddie
  17. Denticle

    Sorry, it's blurry. Hopefully identifiable. It is 3/4" x 1/2". From a late Cretaceous site. Shark or Ray?
  18. Placement of terrestrial formations in the late cretaceous of North America as been constantly evolving and in October 2016 Denver Fowler a Paleontologist at the Museum of the Rockies published a very extensive paper on the subject and updated most units. This is very important when it comes to understanding dinosaur evolution and aids in describing species. This paper is in the process of going through peer review so is subject to change. Fowler DW. (2016) A new correlation of the Cretaceous formations of the Western Interior of the United States, I: Santonian-Maastrichtian formations and dinosaur biostratigraphy. PeerJ Preprints 4:e2554v1https://doi.org/10.7287/peerj.preprints.2554v1 The paper is pretty technical but all of the data is found in this excel file (supplemental information) which is a massive high-resolution stratigraphic chart for all of the formations from the late cretaceous of North America. It's nice to see it all laid out and a great reference source. https://doi.org/10.7287/peerj.preprints.2554v1/supp-1 To make it easy I've broken the chart apart so you can easily see most important dinosaur formations Texas The biggest change came with our understanding the Aguja and Javelina Formations of Texas part of the Tornillo group. The study indicated that the Aguja Formation deposits are only Campanian in age and that the Javelina Formation does not extend into the end of the Cretaceous. Very important when trying to describe species in those formations. Sellers have been comparing the Aguja to the Judith River in Montana well there is a correlation but its deposits are much younger that JR. Eastern Montana, N. Dakota, S. Dakota and Wyoming What I found interesting is that the Hell Creek is much older in Montana than in the adjacent states. The other interesting observation that can been easily be seen on these charts is that the how short a time frame the deposits of the Hell Creek/Lance formation are compared to the other major dinosaur formations. Central Montana Two Medicine and Judith River Formations are the two key formations in this locality Utah and New Mexico Utah depicted on the left and NM on the right Head North to Canada Alberta and Saskatchewan
  19. Lance Formation Micro Tooth

    I have some Lance formation matrix I purchased on that auction site and I have been slowly breaking it down. This is one of my finds. I don't have a scale small enough to measure it against so . . . It is a little smaller than the head of a pin, flea speck. I did a Google image search on Lance Formation micro teeth but came up with nothing. The photos were taken with my Nikon point an shoot through the eyepiece of my microscope. These photos are the best I can do.
  20. Small Vertebra (Hell Creek)

    Any help on the identity and position of this small (scale bar = 1 mm) vertebra from the Hell Creek Formation (Late Cretaceous) of S. Dakota, would be greatly appreciated. It looks like much of the neural arch and processes are gone. The centrum is a bit more dorso-ventrally flattened as compared to the turtle vertebra I posted the other day, and the ventral side (?) of the centrum has sinuses unlike the turtle vert (perhaps due to wear / breakage?).
  21. Richardoestesia isosceles?

    Is this a tooth of Richardoestesia isosceles? Scale marks on left side of tooth are in mm and on the right side are in 0.5 mm increments. Serration count ranges from about 6 to 8 per mm. What remains of the tooth is approximately 11 mm in length. Hell Creek Formation (Late Cretaceous: Maastrichtian), South Dakota.
  22. Hell Creek "Herptile"

    Could someone help me with the identification and position of this vertebra. I was thinking it was procoelous and maybe crocodylomorph? Scale bar = 1mm.
  23. Hi All, I am hoping someone might recognize this bone fragment. It is from the Hell Creek Formation (Late-Cretaceous) of South Dakota. It looks fishy to me but does not have the exterior texture of gar skull. The exterior is really "pocked", almost like small, conchoidal chips. If fish, maybe bowfin, paddlefish, or sturgeon skull fragment? Only other thought I had was maybe crocodilian or champsosaur skull fragment, but I am leaning fish. There might be enough structure on the interior surface for someone to recognize which bone. Top photo is the exterior surface, middle is interior surface, and bottom photo is close-up (under magnification) of the exterior surface. Scale is in cm / mm. Thanks for any help.
  24. Hell Creek Mammal

    Sorry for the barrage of Hell Creek posts, I finally have time to go through some of my summer collections. I am having a hard time with this mammal tooth (Hell Creek Formation, Late-Cretaceous, South Dakota). The occlusal surface is heavily worn. I was thinking perhaps Cimolodon? or Mesodma? Any help / suggestions would be greatly appreciated. Scale bar = 1 mm
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