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I'd like to start by saying I am a complete novice. But I have always been very interested in prehistoric life and paleontology. After recently getting back into the hobby I researched my local area. I have an interest in marine reptiles and was hoping to find a mostly untouched site with the possibility of finding some. Reviewing various bedrock maps and surveys I found one site that might work. I am aware I will need to review permitting and regulations before doing anything but for now i'd like to just identify areas with potential. I was wondering if anyone would help me assess it given the information I have found. Site description: ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Name Jurassic marine rocks ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Geologic age Devonian to Late Jurassic ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Lithologic constituents Major Sedimentary > Clastic > Sandstone (Bed)Feldspathic to volcaniclastic Metamorphic > Metasedimentary > Metaclastic > Slate Minor Igneous > Volcanic (Pyroclastic) Metamorphic > Metasedimentary > Metaclastic > Argillite Incidental Sedimentary > Clastic > Mudstone (Bed) Metamorphic > Metasedimentary > Metaclastic > Quartzite Sedimentary > Clastic > Conglomerate (Bed) Sedimentary > Chemical > Chert (Bed) Igneous > Volcanic > Mafic-volcanic > Andesite (Flow, Volcaniclastic) Sedimentary > Clastic > Siltstone (Bed) Sedimentary > Carbonate > Limestone (Bed) ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Comments Primarily argillite, slate, feldspathic to volcaniclastic sandstone, and pyroclastic rocks. Includes some rocks of Paleozoic age ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Here is my thinking: The geologic age of the rocks ranges from the Devonian to the Late Jurassic. Marine reptiles, such as ichthyosaurs and plesiosaurs, first appeared in the Late Triassic and continued to evolve and diversify throughout the Jurassic. Therefore, rocks from the Late Jurassic are particularly promising for finding marine reptile fossils. The rock types present at this site also suggest a good chance of finding fossils. A large portion of the site consists of sedimentary rocks such as sandstone, mudstone, conglomerate, siltstone, and limestone. These rock types are known to often contain fossils, as they form from the accumulation of sediment, which can include the remains of organisms. Additionally, the presence of marine sedimentary rocks such as limestone is a strong indicator of a past marine environment, where marine reptiles would have lived. Furthermore, although there is some metamorphic rock present, such as slate and argillite, these are low-grade metamorphic rocks that have undergone only mild metamorphism. This type of metamorphism is less likely to destroy fossils compared to the high-grade metamorphism that produces rocks like gneiss and schist which is common in other formations in the area. The presence of volcanic rocks and pyroclastic suggest some volcanic activity, which can sometimes be associated with excellent preservation conditions if organisms are rapidly buried by ash. I am trying to find pictures of the rocks in the area but it is a bit challenging. I'll update the thread if I can find some decent ones. Please let me know your thoughts on this location from a purely geological perspective. Thank you, -Ged

https://news.utexas.edu/2023/06/27/newly-discovered-jurassic-fossils-are-a-texas-first/