The Ruth Mason Quarry presents a fascinating snapshot of time in the Cretaceous world. Perhaps two thousand dinosaurs were wiped out in what appears to have been a single incident. The dinosaurs involved were adult and juvenile Edmontosaurus. The smallest of these appear to have been of minimum size for migrating animals, 1/4 size of the adults. It is believed that flash flooding, during migration season may be the cause of this monumental mishap.

The bones were transported from upstream and deposited down the coastal plain, in a fossil stream channel north of what is now Faith, South Dakota. Some bones were scavenged along the way; all became disarticulated. The scene was completely covered over with sediment and debris within about a five-year period.

This replica skeleton was produced from over 400 original bones found at the Ruth Mason Dinosaur Quarry near Faith, SD. It is lightweight and easy to assemble. Two people can set it up in about an hour! Makes a great display alone, with contemporaries from the Cretaceous, or as part of a migratory herd (much like the herd this one was from). Some of Edmontosaurus’s contemporaries include T. rex, Triceratops, Struthiomimus, ornithomimid, Denversaurus and Packycephalosaurus.

Go to the Edmontosaurus page for more on this species.