Above is several pictures of an unidentified plant fossil found in NW Arkansas this past week in the Dye Shale Member of the Bloyd Formation. The fossil is mostly pyrite with an outer coating of calcite (gray crust). It was found in a shale unit and the original plant, or tree, has been squashed by the weight of sediment above it.
At just over 6 feet long and less than an inch thick, it’s an unusually well preserved fossil, especially considering the Dye Shale isn’t known to contain many fossils. It’s also a marine unit and this is certainly a terrestrial plant. Perhaps it was washed in to the environment during a storm and rapidly buried, which led to its preservation. There are no obvious places where branches or leaves might have attached to the trunk and it has a distinct bark pattern that is unlike the well-known plants of the Pennsylvanian Period, such as lycopods, Lepidodendron, or Calamites.
If any fossil savvy readers have a suggestion for its identity, feel free to pass it along. Otherwise, we’ll keep looking into it.