THE STRATIGRAPHIC UTILITY OF THE TRACE FOSSIL PTERIDICHNITES BISERIATUS IN THE UPPER DEVONIAN OF EASTERN WEST VIRGINIA AND WESTERN VIRGINIA, USA

摘要

Similar lithologies and lithofacies are present in two Upper Devonian siliciclastic units, the Brallier and Foreknobs formations, in eastern West Virginia and western Virginia, USA. Specimens of an unusual trace fossil, Pteridichnites biseriatus, occur in variable numbers throughout both stratigraphic units. P. biseriatus is present in abundance in the lowermost Brallier and this abundance-zone serves as a local stratigraphic marker for the Brallier. The trace fossil, originally suggested as an indication of polychaete or arthropod locomotion, is herein proposed as the locomotion trace of an unidentified ophiuroid.