Dinosaur Tracks Guide

geography Where can Guide to be found? Dinosaur fossils can be found at many locations The Earth’s ocean throughout North America and around the world. basins and continents have not always been Within the eastern United States, most rocks at the the same as we see land surface are either too old or too young to them today. contain dinosaur fossils. However, in a few places of the Connecticut River Valley weathering and erosion exposes rocks of just the right age! The geography of the Earth has changed over hundreds of millions of years, from the time Dinosaur track fossils can be Dinosaur tracks are abundant throughout the of the dinosaurs to the present day. found within the Connecticut Connecticut River Valley region. River Valley, which was part Geologists now know that the continents of an ancient system of rift move at a rate of approximately 1 to 4 valleys that formed during the . How were the tracks made and which centimeters per year as they shift on tectonic birth of the Atlantic Ocean in the dinosaurs made them? plates. That is similar to the rate at which your Late Triassic and Early Jurassic. Image source: fingernails grow! Olsen and Rainforth (2003) (see rectangle on image) . What was the ancient geography of the region like and where can dinosaur tracks During the Today, dinosaur tracks can be seen throughout the Triassic Period, a region preserved in local parks and museums. be seen now? supercontinent known as Pangea Some specific locations include: Answers to these questions can began to break . Amherst College Beneski Museum of Natural History, be found in this illustrated apart as the Amherst, MA educational guide. North American . Barton Cove Campground, Gill, MA and the African . Boston Museum of Science, Boston, MA plates began to . Dinosaur Footprints Reservation, Holyoke, MA separate. . Dinosaur State Park, Rocky Hill, CT The climate was . Nash Dinosaur Track Site and Rock Shop, warm and tropical South Hadley, MA USGS as North America . Powder Hill Dinosaur Park, Middlefield, CT Dilophosaurus, Earth, was much closer . Springfield Science Museum, Springfield, MA

mic a Jurassic‐age dinosaur to the equator. aa . Yale Peabody Museum of Natural History, Dyn

This New Haven, CT This was the Coelophysis, Possible track makers of source: dawn of the age a Triassic‐age dinosaur dinosaur footprints of dinosaurs! Map Content and Design by Daniel A. Vellone, PG, Professional Geologist © 2013 Edited by J. Bret Bennington, PhD, Professor of Geology, Hofstra University within the region How were dinosaur Who made the in the tracks made? Connecticut River Valley? Dinosaur tracks are first made when a dinosaur Dinosaur tracks are called trace fossils. Paleontologists do not know exactly which species of dinosaurs steps in soft sediment (like mud), often along made the tracks found throughout the Connecticut River Valley. This is because very few fossil remains the shoreline of a river or lake (a). After the of actual dinosaur skeletons have been found within this region. Paleontologists compare the size and dinosaur’s foot is removed, an impression is shape of individual tracks to dinosaur skeletons of the same age from elsewhere made, much like when you walk across sand at around the world to determine the size and type of dinosaur that the beach (b). The sediment dries and becomes may have left the impressions. The distance between footprints Coelophysis bauri firm, eventually filling in with additional mud to in a trackway can also be used to estimate the speed at preserve the track (c). which the dinosaur was moving when it made the tracks. Numerous types and sizes of tracks are found within the Connecticut River Valley. Most of these tracks m oo are believed to be made by bipedal theropods – © John Conway meat‐eating dinosaurs that walked upright on Image source: Ontograph Studios (a) (b) (c) two legs. dinosaursrock.c

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Im Coelhlophysis was a small, which dinosaur made a particular fossil predatory dinosaur that lived (d) (e) (f) track, dinosaur tracks are given separate about 200 million years ago, species names from dinosaurs known As the track‐bearing layer is buried beneath during the Late Triassic Period. from skeletons. © Gregory S. Paul other layers over time, the sediment hardens Image source: Princeton Field Guide to Dinosaurs into rock. When exposed by erosion the rock splits along the natural layering and the Eubrontes tracks are large (10‐20 inches) and were made by large, bipedal, theropod dinosaur track fossil is revealed (d) producing dinosaurs similar to Dilophosaurus. These dinosaurs probably reached a length of 20 feet. both a negative (mold) and positive (cast) Anchisauripus tracks (6‐10 inches) were made by medium‐sized, bipedal, theropod impression in the rock (e and f). dinosaurs. These dinosaur probably reached a length of 7 to 10 feet. Grallator tracks (3‐6 inches) were made by small to medium‐sized, bipedal, theropod dinosaurs. These dinosaurs probably reached a length of 3 to 7 feet. Coelophysis or a Image source: similar‐sized dinosaur is believed to be the track maker of Grallator. Olsen et al. (1998) Did you know that the first known dinosaur tracks discovered in the United e e States were fdfound in the CiConnecticut River VVllalley in MhMassachusetts ? Vellon

J. In 1802, a young farm boy named Pliny Moody uncovered dinosaur tracks while plowing a field in Erica South Hadley, MA. Edward Hitchcock, an early American geologist and President of Amherst College,

Photo: extensively researched the dinosaur tracks of the region, though he believed they were made by Dinosaur tracks at Nash Dinosaur Track Site gigantic birds. Today, scientists recognize an evolutionary link between dinosaurs and modern birds.