Marshalltown Formation
| Marshalltown Formation | |
|---|---|
| Stratigraphic range: Middle to Late Campanian, | |
| Type | Geological formation |
| Unit of | Monmouth Group |
| Underlies | Wenonah Formation |
| Overlies | Englishtown Formation |
| Lithology | |
| Primary | Glauconite, sandstone |
| Other | Siderite |
| Location | |
| Region | New Jersey, Delaware |
| Country | United States |
| Type section | |
| Named for | Marshalltown, New Jersey |
The Marshalltown Formation is a Late Cretaceous (Campanian)-aged geologic formation in New Jersey and Delaware, US. Dinosaur remains diagnostic to the genus level are among the fossils that have been recovered from the formation. It contains the most extensive Campanian-aged dinosaur fauna from New Jersey and Delaware.
The famous Ellisdale Fossil Site, a konzentrat-lagerstätten which contains one of the most diverse Cretaceous vertebrate assemblages (likely rapidly buried in a massive flood event) known from eastern North America/former Appalachia, is an exposure of this formation.
The Marshalltown Formation stretches across southern New Jersey to northern Delaware, and is largely composed of marine sediments deposited off the eastern shore of Appalachia, although the Ellisdale site represents a fluvio-deltaic or tidal-estuarine environment reminiscent of the modern Albemarle Sound, and thus has more of a terrestrial influence.