Abstract The stratified red beds of the Catskill Formation are conspicuous in road cut exposures on the Allegheny Plateau of north-central Pennsylvania. During this field trip we will visit and explore several fossil localities within the Catskill Formation. These sites have been central to recent investigations into the nature of Late Devonian continental ecosystems. By the Late Devonian, forests were widespread within seasonally well-watered depositional basins and the spread of plants on land from the late Silurian through the Devonian set the stage for the radiation of animals in both freshwater and terrestrial settings. A diverse assemblage of flora and fauna has been recovered from the Catskill Formation including progymnosperms, lycopsids, spermatophytes, zygopterid and stauripterid ferns, barinophytes, invertebrates and invertebrate traces, and vertebrates such as placoderms, acanthodians, chondrichthyans, actinopterygians, and a variety of sarcopterygians including early tetrapods. Since the early 1990s, highway construction projects along the Route 15 (Interstate 99) have provided a new opportunity for exploration of the Catskill Formation in Lycoming and Tioga counties. The faunas along Route 15 are dominated by Bothriolepis sp. and Holoptychius sp. and also include Sauripterus taylori and an assortment of other interesting records. The most productive Catskill site, and the source of early tetrapod remains, is Red Hill in Clinton County. Red Hill presents a diverse and unique flora and fauna that is distinct from Route 15 sites, and also provides a spectacular section of the alluvial plain deposits of the Duncannon Member of the Catskill Formation.

Abstract The stratified red beds of the Catskill Formation are conspicuous in road cut exposures on the Allegheny Plateau of north-central Pennsylvania. During this field trip we will visit and explore several fossil localities within the Catskill Formation. These sites have been central to recent investigations into the nature of Late Devonian continental ecosystems. By the Late Devonian, forests were widespread within seasonally well-watered depositional basins and the spread of plants on land from the late Silurian through the Devonian set the stage for the radiation of animals in both freshwater and terrestrial settings. A diverse assemblage of flora and fauna has been recovered from the Catskill Formation including progymnosperms, lycopsids, spermatophytes, zygopterid and stauripterid ferns, barinophytes, invertebrates and invertebrate traces, and vertebrates such as placoderms, acanthodians, chondrichthyans, actinopterygians, and a variety of sarcopterygians including early tetrapods. Since the early 1990s, highway construction projects along the Route 15 (Interstate 99) have provided a new opportunity for exploration of the Catskill Formation in Lycoming and Tioga counties. The faunas along Route 15 are dominated by Bothriolepis sp. and Holoptychius sp. and also include Sauripterus taylori and an assortment of other interesting records. The most productive Catskill site, and the source of early tetrapod remains, is Red Hill in Clinton County. Red Hill presents a diverse and unique flora and fauna that is distinct from Route 15 sites, and also provides a spectacular section of the alluvial plain deposits of the Duncannon Member of the Catskill Formation.

ABSTRACT With waterfalls and the deepest gorge in Pennsylvania, Ohiopyle State Park provides opportunities to observe a variety of habitats and three-dimensional (3-D) exposures of the Pennsylvanian sandstone most responsible for shaping Laurel Highlands landscapes. Evidence for the relationship between bedrock, ancient climates, and the landscape can be observed at some of the most scenic natural features of the park: Baughman Rock Overlook, Cucumber Falls, Ohiopyle Falls, Meadow Run Waterslide and Cascades, and Youghiogheny River Entrance Rapid. Channel azimuths and lateral variations in thickness of upper Pottsville fluvial/deltaic sandstone suggest that deposition was influenced by deformation of this part of the Allegheny Plateau during the Alleghanian orogeny. Geologic features of Pottsville sandstone outcrops include a 10-m- (~33-ft-) long Lepidodendron fossil and a 3-D exposure of a meter-high Pennsylvanian subaqueous sand dune and scour pit. Cosmogenic age dating has indicated very slow erosion of hard sandstone in an upland location at Turtlehead Rock and informed estimation of Pleistocene/Holocene waterfall retreat rates of Ohiopyle and Cucumber Falls. Bedrock exposures supporting scour habitats along the Youghiogheny River occur only in a limited area of Youghiogheny Gorge where knickpoint migration and bedrock erosion were relatively recent. Geologic factors, including locations of major tributaries, development of bars that constrict river flow, and proximity of Homewood sandstone outcrops as sources of boulder obstacles in the river, contributed to the class, location, and nature of whitewater rapids in the lower Youghiogheny River.

Abstract The Allegheny Portage Railroad, just one leg of the Pennsylvania Mainline Canal system, was the first railroad over the Allegheny Mountains, an imposing physiographic barrier to westward migration in the early 1800s. Construction of the canal system began in 1826 and continued until ca. 1840 without interruption. The Allegheny Portage Railroad began construction in 1831 and opened for business in 1834. This astonishing engineering feat took less than four years for completion, despite the necessity of 10 inclined planes and the use of the new-fangled railroad locomotives. Construction made use of many of the natural resources occurring along and adjacent to the right-of-way, especially the Pennsylvanian-aged sandstones used for the “sleepers” that held the rails in place. Travel occurred in sectional canal boats, boats that were built in two or three pieces that could be easily loaded onto rail cars. Passengers and goods were loaded onto the boat sections in Philadelphia, which were then hauled by horse or locomotive to the Susquehanna River west of Lancaster. The boats traveled north on the Susquehanna River canal to the mouth of the Juniata River north of Harrisburg, then along the Juniata River canal to Hollidaysburg near the foot of Allegheny Mountain. There, the boats were taken from the water, loaded onto rail cars, and hauled over the mountain on the Allegheny Portage Railroad to Johnstown where they were unloaded into the Conemaugh River canal for the journey to Pittsburgh. A New Allegheny Portage Railroad was built in the 1850s to bypass the inclined planes. It was no sooner built, however, when the state sold the entire canal system to the Pennsylvania Railroad for less than half the cost of construction. The Pennsylvania Railroad promptly dismantled the Allegheny Portage Railroad and filled in the canals. Today, the Allegheny Portage Railroad National Historic Site oversees and administers the preservation of the few remaining aspects of the old railroad.

Abstract The Allegheny Portage Railroad, just one leg of the Pennsylvania Mainline Canal system, was the first railroad over the Allegheny Mountains, an imposing physiographic barrier to westward migration in the early 1800s. Construction of the canal system began in 1826 and continued until ca. 1840 without interruption. The Allegheny Portage Railroad began construction in 1831 and opened for business in 1834. This astonishing engineering feat took less than four years for completion, despite the necessity of 10 inclined planes and the use of the new-fangled railroad locomotives. Construction made use of many of the natural resources occurring along and adjacent to the right-of-way, especially the Pennsylvanian-aged sandstones used for the “sleepers” that held the rails in place. Travel occurred in sectional canal boats, boats that were built in two or three pieces that could be easily loaded onto rail cars. Passengers and goods were loaded onto the boat sections in Philadelphia, which were then hauled by horse or locomotive to the Susquehanna River west of Lancaster. The boats traveled north on the Susquehanna River canal to the mouth of the Juniata River north of Harrisburg, then along the Juniata River canal to Hollidaysburg near the foot of Allegheny Mountain. There, the boats were taken from the water, loaded onto rail cars, and hauled over the mountain on the Allegheny Portage Railroad to Johnstown where they were unloaded into the Conemaugh River canal for the journey to Pittsburgh. A New Allegheny Portage Railroad was built in the 1850s to bypass the inclined planes. It was no sooner built, however, when the state sold the entire canal system to the Pennsylvania Railroad for less than half the cost of construction. The Pennsylvania Railroad promptly dismantled the Allegheny Portage Railroad and filled in the canals. Today, the Allegheny Portage Railroad National Historic Site oversees and administers the preservation of the few remaining aspects of the old railroad.