Trace fossils in the Mississippian of Ohio, USA.

The Vinton Member is the uppermost of four stratigraphic units in the Mississippian-aged, siliciclastics-dominated Logan Formation of eastern Ohio. Ascending from the base, they are the Berne Conglomerate Member, the Byer Sandstone Member, the Allensville Member, and the Vinton Member. The Vinton is dominated by sandstones, siltstones, and shales deposited in relatively shallow marine facies.

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.

The photo shows horizontal burrows atop a sandstone bed having compressed ripple marks. In very shallow, high-energy marine facies, burrows are vertically-oriented. In lower energy, offshore facies, burrows tend to be horizontally oriented. The Vinton Member is a relatively shallow marine deposit, but it does not represent a near-shoreline or shoreface environment.

Stratigraphy: Vinton Member, upper Logan Formation, Osagean Stage, upper Lower Mississippian