PALEOENVIRONMENTAL STRATIGRAPHIC RECONSTRUCTION AND CONTROL ON THE DISTRIBUTION OF THE LOWER KEYSER FORMATION OF CENTRAL PENNSYLVANIA

For long periods of geologic time, shallow inland tropical seas were the primary depositional regimes of the Appalachian Basin. The Silurian-Devonian carbonate sequence provides exemplary records of this sedimentation, with one such example being the time-transgressive Keyser Formation. Keyser lithofacies represents deposition upon an epeiric ramp across a range of shallow marine environments. However, varying interpretation of these lithofacies has led to inconsistencies in the literature that must be dealt with to ensure proper attempts are made at correlations on a local scale.

In West-Central Pennsylvania, a unique package of strata occupies the lower Keyser, which differs remarkably from the established lithology currently in use for the state. Here, the distribution of this lithological change is mapped through outcrop exposure and its controls are hypothesized. Transgressive-regressive cycle sedimentation and event correlation are used to create a paleoenvironmental stratigraphic reconstruction for Central Pennsylvania as a means of clarifying the variation in lithofacies encountered throughout Keyser stratigraphy.