Eubrontes dinosaur track from the Jurassic of Connecticut, USA.
Trace fossils are any indirect evidence of ancient life. They refer to features in rocks that do not represent parts of the body of a once-living organism. Traces include footprints, tracks, trails, burrows, borings, and bitemarks. Body fossils provide information about the morphology of ancient organisms, while trace fossils provide information about the behavior of ancient life forms. Interpreting trace fossils and determination of the identity of a trace maker can be straightforward (for example, a dinosaur footprint represents walking behavior) or not. Sediments that have trace fossils are said to be bioturbated. Burrowed textures in sedimentary rocks are referred to as bioturbation. Trace fossils have scientific names assigned to them, in the same style & manner as living organisms or body fossils.
This track was made by a theropod, a group of small to large, carnivorous, bipedal dinosaurs. The specimen comes from a Triassic to Jurassic terrestrial sedimentary succession that filled up a half graben, many of which occur along America's eastern seaboard. Such half-graben basins formed during the Triassic as the Pangaea supercontinent tried to rift apart, but failed. Pangaea successfully broke apart during the Jurassic.
Stratigraphy: East Berlin Formation, Newark Supergroup, Lower Jurassic
Locality: unrecorded / undisclosed site at or near the town of Rocky Hill, central Connecticut, USA
Info. at:
mrdata.usgs.gov/geology/state/sgmc-unit.php?unit=CTJeb%3B0
and
en.wikipedia.org/wiki/Eubrontes
