sentences:  Very few fossils exist in the Bald Eagle Formation, and most of them are trace fossils.However, at the base of the formation is the "Orthorynchula" biostratigraphic marker bed, which contains abundant "Orthorynchula" brachiopods.Relative age dating of the Bald Eagle places it in the Upper Ordovician period, being deposited between 488.3 and 443.7 (±10) million years ago.