DETERMINATION OF THE GEOLOGIC STRUCTURAL CONFIGURATION OF THE EAGLES MERE QUADRANGLE

In this project, the author redefines the upper and lower contacts of the Mississippian age Burgoon sandstone in the central portion of the Eagles Mere 7.5-minute quadrangle, Sullivan County, PA and addresses the inconsistencies of the contacts as shown on the geologic map of Berg (1977). Berg (1977) relied primarily on aerial photographs augmented by reconnaissance mapping to delineate stratigraphic contacts. The outcrop width of the Burgoon sandstone as shown on the Berg (1977) map is anomalously wide given the known thickness and regional dip of the Burgoon sandstone in the Eagles Mere area. This anomalous width may be explained by (1) inaccurately placed lithologic contacts on the Berg (1977) map, (2) folding of the Burgoon sandstone, (3) faulting of the Burgoon sandstone, or (4) a combination of the three. Detailed mapping of this area, completed by the author, demonstrates that the lithologic contacts of the Burgoon sandstone were largely incorrect on geologic map of Berg (1977). The distribution of Burgoon outcrop as mapped in this study suggests that the area may also contain previously unrecognized structural complexities. We also demonstrate the presence of previously unrecognized red beds in the upper portion of the Huntley Mountain formation underlying the Burgoon sandstone in this area. Berg suggested that the uppermost of these red beds be designated as the boundary between the two formations. Seismic refraction has determined the attitude and thickness of this red-bed to be approximately two meters thick and sub-horizontal where tested.