DINOSAURS OF THE DISTRICT OF COLUMBIA

For more than 100 years, dinosaur fossils have been found within the District of Columbia’s 69 square miles. To date, all of the discoveries have been in mid-Cretaceous beds (Potomac Group, Aptian). Upper Cretaceous marine sediments (Severn Formation, Maastrichtian), which have yielded dinosaur fossils in Maryland, have not yet produced dinosaur remains within the District.

Three identifiable dinosaur groups are known from fossil remains, “Capitalsaurus”, a probable tyrannosaur, was found in 1898. Astrodon, a sauropod, was found in 1942. A raptor-like dinosaur was found in 1959. There have been unconfirmed reports of other dinosaur finds, but as yet none of these can be documented.

All of the discoveries have been recovered in the course of normal construction activities which go on daily in the city. As there is very little outcrop, it is likely that future finds will follow a similar pattern. In order to maximize the recovery of new fossil discoveries, public awareness of the existing fossils is essential.