East Waterford (new name) consists of red graywacke-type sandstones with interbeds of shale and siltstone. Assigned to Juniata formation as basal member from Tyrone Gap to Susquehanna Gap. Underlies Plummer Hollow red mudstone and sandstone member (new) of Juniata from Tyrone Gap eastward to about vicinity of Lost Creek Gap. Overlies Spring Mount sandstone member (new) of Bald Eagle sandstone; eastward overlies Lost Run conglomerate. Age is Ordovician (Cincinnatian).

Source: GNU records (USGS DDS-6; Reston GNULEX).

Subdivision of the Juniata Formation into three members in central PA is based largely on differences in the relative proportion of sandstone and mudrock. In the lowest East Waterford Member (lithofacies D of this report) red sandstones dominate over dark red mudrocks, and the sandstones are organized into beds that are medium to thick, cross-laminated, and laterally extensive and sheet-like. The middle Plummer Hollow Member (lithofacies E) contains more mudrock than sandstone, and the sandstone and mudrock are more or less regularly interbedded, in some places as fining-upward sequences. Abundant SKOLITHOS-like burrows filled with red mudstone occur in the sandstone. The upper Run Gap Member (lithofacies F) is largely red lithic wacke and underlies quartz arenite at the base of the Tuscarora Formation. Age is Ashgillian.

Source: GNU records (USGS DDS-6; Reston GNULEX).