To log this Earthcache, send an email with the following information:
- Breathitt Formation EarthCache, GC4YFNM
- Estimate the thickness of the Breathitt Formation (the tan rock)
- Locate some fossils and do your best to identify what you have found. Describe the size, shape and your best identification of what you have found. What was the most common type you found at this site?
{OPTIONAL but encouraged}Post a picture of your find and your best identification. This will create a database for researchers.
The law of super-positioning states, left undisturbed, older sediments are on the bottom of a geologic column and newer sediments are on top. This law allows us to look back through prehistoric history and start to understand what life may have dominated our planet in different periods of time. Each geologic period creates a new layer of fossils, sediments and clues from earth’s past.
When there is a separation in the rock layers it is called an unconformity. Unconformities can be caused when sediments stop depositing. A new layer will form when sediments begin to deposit again.
A little over 300 million years ago, scientists believe planet earth was covered with thick, diverse swamps. This may have been one of the most diverse ecosystems of plants and animals on our planet. These swamps were believed to be shallow seas that may have been as large as the current Pacific Ocean. This was the Pennsylvanian period, one that lasted roughly 20 million years. During this time, the plant and animal remains that were buried formed our thickest coal deposits we mine today.
Near the beginning of this period, a layer rich in silt buried plants and animals creating a nearly five foot thick layer of fossils. This layer is characterized by a tan colored silt rock rich in dark carbon rich fossils that are easily identified. This is the Breathitt Formation. This formation is believed to cover most of eastern Kentucky and Tennessee and is currently below the thick layer of Pennsylvanian coal.
About 250 million years ago, when the supercontinent Pangea formed, the tectonic plates pushed against each other, building the Appalachian Mountain Range to the east. This tectonic pressure caused the once buried sea to lift high above the ocean floor. Weathering and erosion over time removed the top layers and finally exposing once again, the Breathitt Formation.
The location you are standing is one of the best examples of Breathitt Formation Fossils. Geology students from at least 10 major universities come here to examine and study the fossils. Dozens of invertebrate and hundreds of plant species have been found and identified in this location alone. These fossils date to the early part of the Pennsylvanian Period, nearly 320-340 million years ago. This formation was originally identified in Breathitt County, KY in the late 1890’s. About 40 Breathitt Formation locations have been identified, but the best preserved and complete fossils have been found here.
There are several publications and online resources to help you identify the fossils you can find at this location.
http://www.dcnr.state.pa.us/cs/groups/public/documents/document/dcnr_014599.pdf
http://identifyfossils.com/fwlinksPA.shtml
Your task is to locate and identify fossils. Post pictures of your finds and what you have identified. Your discoveries and documentation can help broaden the research at this location.
Congratulations to psyprof and cynwood on the FTF!