Location Rocks of Ordovician through Mississippian age are exposedalong roads and railroads paralleling the Lehigh River between Palmerton and Jim Thorpe in Carbon County, Pennsylvania (Fig. 1). Rocks of the Ordovician Martinsburg Formation and the Silurian Shawangunk Formation are well exposed on the eastside of Lehigh Gap along an abandoned railroad bed (Fig. 2). Anunmaintained access road along the railroad bed is reached from Pennsylvania 248 just east of the former railroad overpass or byclimbing the slope near the east end of the bridge across the Lehigh River (Fig. 2). Part of the Silurian Bloomsburg Formationis exposed along a small side road paralleling Pennsylvania 248 (Fig. 2). This road is accessed from Delaware Avenue in Palmertonor Pennsylvania 248 just south of Aquashicola Creek. Several Lower, Middle, and Upper Devonian rock units arebeautifully exposed at Bowmanstown (Fig. 2). These exposuresare reached by exiting from Pennsylvania 248 to Bowmanstown. The Devonian Ridgeley (Oriskany), Schoharie-Esopus, Palmerton, Buttermilk Falls, and Marcellus Formations (Fig. 3) areexposed in a deep roadcut along the Northeast Extension Pennsylvania Turnpike at West Bowmans. Proceed west on Pennsylvania 895 from Pennsylvania 248 and park in a pull-off areaon the north side of the road at the east end of the bridge over theturnpike. It is possible to go over the southeast side of the bridge

The Devonian Catskill Formation has been divided into four magnafacies (Mf) which have been correlated throughout Pennsylvania. Lithologies in 28 sections and wells were assigned to 10 facies on the basis of grain size, color, bed forms, fossils, and other sedimentary features. Repeating patterns of facies were used to identify magnafacies. Mf-A, the basal magnafacies, is composed dominantly of interbedded marine and non-marine shale and fine sandstone and is inferred to have been deposited mainly in a mud-rich tidal-flat environment. Mf-B is dominated by thick red shales accompanied by thin, fine-grained sandstones and is interpreted as a low-energy fluvial deposit on an inactive arid coastal plain. Mf-B is interrupted occasionally by thin, transgressive sandstones of tidal origin. Mf-C is composed of thick sandstones deposited by braided rivers and localized in three major northwest-trending zones of sediment input. Mf-D is composed of thick, fining-upward cycles with sub-equal amounts of sandstone and red shale. It is inferred to have been deposited by meandering rivers and is thickest in the same areas that Mf-C is thick. Mf-A and Mf-B are richer in sand near the sediment-input centers. In most sections, the Mf are present in the order A, B, C, and D upward, with C missing in many areas and more complex relations in extreme northeastern Pennsylvania. All Mf tend to thin northwestward. This pattern of distribution presumably results from northwestward progradation of the fluvial environment. Numerous small non-economic Cu-U occurrences are concentrated in areas of thick, shale-rich Mf-B lying between the major sediment-input areas. Most are closely associated with marine transgressions. A few occurrences are in the upper part of Mf-A and in Mf-D, but none is in Mf-C. Most of the Cu-U occurrences are localized by small accumulations of plant trash in shallow fluvial or tidal channels. In contrast, Wyoming-type, roll-front uranium occurrences are localized near Jim Thorpe in large channel sandstones of thick Mf-D in the sediment-input areas. The Cu and U occurrences appear to have formed during diagenesis by migration of metalliferous pore fluids.

Abstract The thickest and most laterally continuous upper Carboniferous molasse in the central Appalachians is located in the Southern Anthracite Field of northeastern Pennsylvania. Substantial deposits extend throughout northeastern Pennsylvania where >90% of the total anthracite (original reserves) in the United States and the thickest coal beds of the eastern United States are located. The abundance of and demand for this resource allowed the region to prosper in the nineteenth and twentieth centuries. In Pottsville, Pennsylvania, the exposed Upper Mississippian to Middle Pennsylvanian molasse reveals a progressive evolution from a semiarid alluvial plain to a semihumid alluvial plain to a humid alluvial plain. The anthracite beds occur and thicken with increased humid conditions. The progression is also exposed in Tamaqua, Pennsylvania, where convenient access to the underlying Lower Mississippian strata is available, thus providing a section of all Carboniferous formations in the region. Finally, in Lansford, Pennsylvania, a renovated deep anthracite mine illustrates the historical methods and working conditions that existed to extract the valuable resource and allow the region to flourish and fuel the Industrial Revolution.

Abstract Stratigraphy, from the Latin stratum and the Greek graphia, has traditionally been considered the descriptive science of rock strata. In the last few decades, the critical value to stratigraphy of the information provided by nonlayered rock bodies—sedimentary as well as intrusive igneous rocks and massive metamorphic rocks of undetermined origin—has become evident. Non-layered rock bodies not only are the source of geochronometric (numerical) ages determined by isotopic methods, but they also provide crucial age information through the establishment of their cross-cutting and boundary relationships with layered and/or nonlayered rocks with which they are associated. The definition of stratigraphy should, therefore, be broadened to include the description of all rock bodies forming the Earth's crust and their organization into distinctive, useful, mappable units based on their inherent properties or attributes. Stratigraphic procedures include the description, classification, naming and correlation of these units for the purpose of establishing their relationship in space and their succession in time. As such, stratigraphy is concerned not only with the original succession and age relations of rock bodies, but also with their distribution, lith-ologic composition, fossil content, and geophysical and geochemical properties—indeed, with all observed properties and attributes of rock bodies and their interpretation in terms of environment or mode of origin and of geologic history. All classes of rocks—igneous and metamorphic as well as sedimentary, unconsolidated as well as consolidated—fall within the general scope of stratigraphy and stratigraphic classification.