Geochemical Comparison of Karst and Clastic Springs in the Appalachian Valley & Ridge Province, Southeastern West Virginia and Central Pennsylvania

The Appalachian Valley and Ridge (V&R) Province extends over 11 states and is an essential water supply. The regional geology consists of more resistant clastic rocks, typically sandstones and mixed shales, which form the ridge tops and mountain flanks, and carbonate rocks that underlie the valleys. In this study, we report the geochemistry of different types of springs on and near Peter’s Mountain in Monroe County, WV. More than 250 springs have been mapped in the ~225 km2 study area on and adjacent to Peter’s Mountain. These data are compared with preliminary data collected from sandstone-sourced springs from central PA and northcentral WV. Six sandstone springs in WV and PA were sampled and monitored for comparison to the Monroe County springs. Springs were grouped by geologic and geomorphologic location: Group 1: sandstone-sourced springs in WV and PA; Group 2: springs in the Martinsburg Formation on the western flank of Peter’s Mountain; and, Group 3: springs in the carbonate valley west of Peter’s Mountain. In general, Group 1 springs are smaller and more ephemeral than the other groups; their waters have low pHs (4.1-6.0), low specific conductivities (24 to 55 μS/cm), and low concentrations of dissolved ions. Group 2 springs are also small and ephemeral but have higher pHs (6.7 -8.4) and specific conductivities (73-308 μS/cm) due to the mixture of shales and carbonates in the source formation. Temperatures in these springs range from highly consistent to highly variable. Although the Group 2 springs along Peter’s Mountain have Ca and Mg concentrations similar to the Group 3 carbonate springs, they can be distinguished by higher Ca/Mg mole ratios. In contrast, Group 3 springs have higher pHs (6.6-8.4) and higher specific conductivities (144-750 μS/cm).