Geophysical characterization of the Precambrian basement in northwest Pennsylvania, U. S.

Summary Few integrated studies combining different geophysical data sets have concentrated on the Precambrian basement in the northwestern part of the Pennsylvanian Appalachian basin. In this study, we present an indirect method for characterizing the structure and composition of the Precambrian basement utilizing newly acquired magnetic and gravity data. Depth-to-basement estimates made by using the radially averaged power spectrum analysis, Standard Euler calculations and 3-D model inversions over the gravity and magnetic data indicate general agreement with a sedimentary basin having a base at approximately −9,000 to up to −15,000 ft subsea. A gently dipping Precambrian basement with laterally varied density and magnetic susceptibility with a significant high susceptibility area found within the basement likely due to lithological variations within this unit. These results may have implications for areas of enhanced oil and gas production found within the region.