Pg. 8 (table 1), 11 (table 3), 57. Zullinger Formation of Conococheague Group. Consists of cyclically-bedded stromatolitic-mechanical limestone, interbanded limestone and dolomite, interlaminated limestone and dolomite, and thin dolomite. Several thin local quartz sand beds. Thickness 2,500 feet. Underlies Shadygrove [Shady Grove] Formation (new). Overlies Elbrook Formation. Age is Late Cambrian.
Described from Cumberland Valley, southeastern Franklin Co., central southern PA.

Source: US geologic names lexicon (USGS Bull. 1350, p. 846).

Named for Zullinger, Franklin Co., PA. Type section is road cuts 1 mile west of Zullinger on State Highway 16. Zullinger used to be lower part of Conococheague Formation. This paper raised the Conococheague to group rank and divided it into a lower Zullinger Formation and an upper Shadygrove Formation. Zullinger is composed of blue-gray limestone frequently interbedded within dark blue-gray dolomite. Basal 115 feet is 3 to 4 foot thick beds of interbanded limestone and dolomite with subordinate interbeds of mechanical and algal limestone. Above this are 5 feet of sandy dolomite and 87 feet of algal and mechanical limestone. Algal pipes and clastic filled channels are prominent. The main body of the formation is composed of approximately 1550 feet of cyclical carbonates. Thickness of formation is probably 2500 feet. Conformably overlies Elbrook Formation; underlies Shadygrove Formation. Trilobites suggest late Dresbachian to Trempealeauan age (Late Cambrian), however, stratigraphic column shows Middle and Upper Cambrian. Geologic map included in report.

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

Used Zullinger Formation on correlation chart for PA. Upper Cambrian.

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