- Definitions (Source: thefreedictionary.com)
- slickenside: a polished, striated rock surface caused by one rock mass sliding over another in a fault plane
- playa: a nearly level area at the bottom of an undrained desert basin, sometimes temporarily covered with water
- Even though dinosaurs became extinct dozens of millions of years ago, their remnants, mainly in the forms of fossilized bones and footprints, allow us to infer many things about their lifestyles. The size of the prints can allow archaeologists to determine the size of their feet, and extrapolate that to their height, length, weight, body shape, and posture. They can also provide insight into how they walked and got around. Bones might give us a more accurate representation of their size and anatomy, especially when they are fully assembled into skeletons, but footprints should not be discounted, especially since they provide their own valuable information, and can even be correlated with the bones. On the other hand, these fossils cannot really tell us their specific diets; it can be inferred that they ate plants and animals based on their range of motion, but the exact species cannot be determined. Also, they cannot really tell us anything about their organs, internal body systems, or outer coverings or skin.
Tag: Field Trip
Field Trip Response
Most of the fossils and footprints found in the Connecticut Valley are from the Triassic and Jurassic periods (found by radiometric dating of basalt layers), which is when the Hartford Basin was formed. The Hartford South quadrangle has the youngest formations, including the East Berlin Formation which contains tracks of Eubrontes and other dinosaur footprints. In the black shale layers there are also fish fossils. In the New Haven arkose, Newark group, and Portland arkose are the remains of plants and animals from the Triassic period. The fossils are grouped into 2 categories: the impressions left in the sediments by living things and the actual fossilized remains of plants and animals.
These are all pretty great and cool and everything, but just because they’re there, doesn’t mean we can start painting a picture of how everything was and how these creatures found there way there. For example, the fossils found there don’t necessarily tell us all the creatures that lived there. There were several dinosaurs represented by the bones: Anchisaurus, Ammosaurus, Coelophys, Yaleosuarus. These all share similarities, but they don’t mean there weren’t other, completely different dinosaurs lurking about. What do footprints tell us? Well, they’re the markers of the comings and goings of creatures. And that’s what makes me question, and it makes Baird question too, whether the tracks show dinosaurs they haven’t found the bones of. There could be ones who migrated through the area seasonally for food or mating. Sure, prosauropods were the most abundant, but maybe they were there for only a specific time period that just so happened to coincide with their death?
arkose: a granular sedimentary rock composed of quartz and feldspar or mica;a feldspathic sandstone
lithology: the physical characteristics of a rock or stratigraphic unit.
