PREHISTORIC PALEONTOLOGISTS OF THE MIMBRES VALLEY, NEW MEXICO
Taxa represented in the fossil collection include brachiopods, bryozoans, corals, and crinoids. Fossil identification combined with previous geologic mapping of the region indicate that the Harris fossils originated from the Percha Shale (Devonian) and the Lake Valley Formation (Mississippian). The Box Member (late Famennian) of the Percha Shale is characterized by interbedded calcareous shales and limestone. This member contains a diverse assemblage of brachiopods and solitary rugose corals. The succession is disconformably overlain by the Lake Valley Formation. The Nunn Member (Tournaisian- Visean) of the Lake Valley Formation is a fossiliferous interval of interbedded shale and limestone. Abundant crinoids are present in this member. Outcrops of these formations are found approximately 4 km west of the Harris Site in the Georgetown region of the Pinos Altos Range.