CONTINENTAL AND MARINE ICHNOLOGY OF THE UPPER DEVONIAN (FAMENNIAN) CATSKILL AND LOCK HAVEN FORMATIONS, NORTH-CENTRAL PENNSYLVANIA: IMPLICATIONS FOR INTERPRETING PALEOENVIRONMENT AND PALEOSALINITY

Results from our study-in-progress demonstrate that the Upper Devonian (Famennian) Catskill Formation (Fm) contains trace fossil-lithofacies associations that represent continental, transitional, and marine environments. Marine trace fossil-lithofacies associations in the Catskill Fm were compared with those of the underlying and interfingering Lock Haven Fm, including in its type section, to confirm that transitional and marine environments are, in fact, recorded in the classic continental successions of the Catskill Fm. Localities include Blossburg, Burlington, Canton, Covington, Lock Haven, Mill Creek, Ralston, Red Hill, Steam Valley, Tioga, and Trout Run.

The Catskill Fm contains lithofacies associations deposited in continental, transitional, and marine environments. Beaconites, Camborygma, Kouphichnium, Lockeia, lungfish burrows, Naktodemasis, Palaeophycus, Paleohelcura, Planolites, cf. Reniformichnus, scorpion burrows, Sagittichnus, Scoyenia, Steinichnus, and Undichna, as well as rhizoliths, rhizohaloes, and rhizocretions occur in proximal and distal fluvial-alluvial deposits. Most fluvial overbank deposits exhibit weak pedogenic modification, with some intervals of moderate to strong pedogenic modification. Kouphichnium, Palaeophycus, Planolites, Skolithos, and Teichichnus occur in transitional deposits. Acanthorhaphe, Arenicolites, Asteriacites, Belorhaphe, Berguaeria, Chondrites, Conichnus, Cruziana, Curvolithes, Diplichnites, Diplocraterion, Gyrolithes, Helicoichnus, Kouphichnium, Lingulichnus, Lockeia, Monocraterion, Olivollites, Parahaentzchelania, Phycodes, Rhizocorallium, Rosselia, Rusophycus, Sagittichnus, Scolicia, Selenichnites, Thalassinoides, Treptichnus, and Undichna occur in strata deposited under brackish to normal marine salinities. This includes strata mapped as Catskill Fm (Burlington) and Lock Haven Fm (Covington, Tioga, Lock Haven).

The marine and transitional trace fossil-lithofacies associations of the Catskill and Lock Haven fms share Planolites, Palaeophycus, and Teichichnus in thin, flaser, wavy, and lenticular interbedded sandstone and mudstone. The Lock Haven Fm consists of lithofacies association deposited by fluvial-, deltaic- and tidally-influenced shallow marine environments.