Sixty-five million years ago, Mantua, New Jersey was on a continental shelf under the Atlantic Ocean.
The water was warm, and the beach nearby was covered with mangrove trees. The organisms found at the quarry may have lived underwater on the continental shelf, traveled through the open ocean, or lived nearby on land. The land-dwellers floated out to sea, eventually sinking to the bottom to be buried here, in the green sand.
Explore the habitats that creatures here lived in when they were alive:
Below the sea floor, in the sand
Many of the clams and snails found here would have buried themselves in the sand at the bottom of the sea. Animals that live like this are called “infaunal”. Since they were already buried when they were alive, they have an excellent chance of fossilizing, which means we probably have a more complete record of these types of animals than any other found at the quarry.
The sea floor
The seafloor is a diverse landscape that parallels the land in many ways. Some animals lived attached to rocks, others crawled around on legs or slimy snail-feet, and some probably looked more like plants than animals. It’s likely there were plants here, too, in fact – but they haven’t been preserved in the fossil record. Animals that live on the seafloor are called “epifaunal” and include the vast majority of animals we find at the quarry, like clams, oysters, snails, shrimp, lobsters, sea urchins and sponges.
The open ocean
Think fish, sea turtles, sharks, rays, and mosasaurs. Everything that swims through the waters of the open ocean is called “nektonic.”
Even though this location was under the Atlantic Ocean at the time when the fossils were deposited here, some of the fossils we find are from organisms that lived on land. How they got here can’t be known for sure, but they probably died on the beach or in a stream and floated out to sea, sinking here to be buried in the sand with everything else. Animals and plants that live on land are called “terrestrial” and the ones we find at the quarry are mostly birds and reptiles. We’ve also found part of one hadrosaur skeleton, and a few bits of wood from trees that grew on land.