If you’re like me, when you think about fossils in the eastern USA, you probably think of either Cenozoic fossils along the eastern and gulf coasts (e.g. Miocene/Pliocene/Pleistocene shark teeth, whale vertebra, and shells in Virginia and the Carolinas) or Paleozoic fossils further inland (e.g. Cambrian trilobites in Georgia or Carboniferous plants in Pennsylvania).
Or, if you live in the Piedmont and Blue Ridge areas of the Appalachian mountains like we did until last year, you don’t think about fossils at all, because all you have are igneous and metamorphic rocks!
Less well-known, however, is that the eastern USA has good Mesozoic (the “age of dinosaurs”) deposits, including Triassic, Jurassic, and Cretaceous fossils. The first reasonably complete dinosaur discovered anywhere in the world was the Cretaceous Hadrosaurus foulkii, found in New Jersey in 1858. While not as extensive as the Cretaceous exposures in the east, the eastern USA has a series of long Triassic and lower Jurassic basins running roughly parallel with the coast. One of the best fossil sites in these basins is the Solite Quarry.
Note: The Solite Quarry is privately owned and not open to the public. It is an active quarry, and both dangerous and illegal to trespass on the property. We excavate at the Solite Quarry as volunteers with the Virginia Museum of Natural History.
Located near the border of North Carolina and Virginia, the Solite Quarry is composed of layers of shale, mudstone, and sandstone that may represent an upper Triassic, shallow, rift valley lake. The Solite is known as a Konservat-Lagerstätte, a German paleontological term roughly translated “conservation storage place” (I prefer to think of it “preservation mother lode!”). A Konservat-Lagerstätte is a place where fossils are preserved extraordinarily well, and Solite is famous for the details visible on Triassic insects. These insects are found in a narrow bed only a few centimeters thick. Just above this insect layer is a second thin bed that preserves the remains of plants, fish, reptiles, and “clam shrimp” (formerly, “conchostracans,” which they’re still often called).
While the insects are usually too small to see, plenty of visible fossils are found in the “fish bed” above. Plant parts and seeds are found on occasion (I found a Fraxinopsis, shown here) but the real star of the Solite is the amazingly preserved fish and reptiles. The most common reptile here is the presumably aquatic Tanytrachelos ahynis (illustration of a swimming one here) a smaller relative of the better-known long-necked Tanystropheus (learn about the latter here and here). Tanytrachelos was an archosauromorph reptile. This means that it was related to the archosaurs, a group of reptiles which includes crocodilians, pterosaurs, and dinosaurs. In life, however, they probably looked something like a cross between a lizard and a salamander. While dinosaurs tend to get all the attention, there are certainly many other fascinating reptiles that lived during the Mesozoic!
While I enjoy collecting fossils for myself, that’s not our purpose at the Solite, and we do not keep these specimens. They are scientifically important, and are placed in the Virginia Museum of Natural History for research and preservation.
The Solite Quarry is part of the Carnian Triassic Cow Branch Formation. Although no dinosaur body fossils have been found in the Solite, dinosaurs and pterosaurs have been found in formations of similar depth, and ichnofossils (trace fossils) indicate that dinosaurs walked here.
Next time, I’ll talk more about the experience collecting and other species found here.
To be continued…