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Where have dinosaurs been found in the United States


The United States is one of the places where it's easy to find fossils and you might be surprised to know that almost every state has dinosaurs. New Jersey was the very first state to identify and name a dinosaur—the Hadrosaurus—which was found in New Jersey in 1838. The state actually boasts six different species of dinosaur fossils. However, when we think of dinosaurs in the US, we mostly think of the western and southwestern United States. These areas of the United States lay claim to the most abundant dinosaur fossils, but dinosaurs have also been found as far north as Alaska and as far south as Alabama.


A little dinosaur geography

During the Cretaceous, the Western Interior Seaway split North America in two. This seaway ran from Montana to New Mexico (and extended into Canada and Mexico). The seaway essentially divided the country into two “island continents;” to the west was Laramidia and to the east was Appalachia. Laramidia in the west had a lot of sediment deposited in freshwater or near the shore. Fast forward tens of millions of years and the sediment in this part of the country continues to erode and expose fossil bearing layers.


The eastern island continent called Appalachia was itself eroding in the late Cretaceous, so bones weren’t given the time to fossilize. That’s not to say that the eastern US doesn’t have dinosaurs. They do exist, but they are mostly found close to the Atlantic Ocean which fed the fossils to the sea creatures. They’re there, they are just much more rare.


Dinosaurs continue to fascinate not only children and paleontologists, but most of us who are intrigued to think of these creatures who roamed the earth millions of years ago. If you want to indulge your inner paleontologist and find your own dinosaur fossils, go on a dinosaur dig for your next vacation.

See a list of where dinosaurs found in the United States






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