Hamburg Member of Leithsville Formation here named in Sussex Co., northern NJ. Described as rhythmically bedded cycles of dolomite, shale, siltstone, and sandstone representative of mudflat to lagoonal environments. 95 ft (29 m) thick at type section west of Hamburg. Underlies Wallkill Member and overlies Califon Member, both of Leithsville Formation. Age is Early Cambrian.

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

The Hamburg Member of the Leithsville Formation is 85 to 100 ft thick at its type section. According to the author, this member has been found in southern NY, NJ, and eastern PA and is described as a rhythmically bedded series of sedimentary cycles ranging from 35 to 100 ft thick. It may consist of dark, organic, laminated to thinly bedded, dense dolomite and shale; light- to dark-gray, locally brownish-gray to green cyclical units of fine to coarse sandstone, siltstone, shale and very fine grained dolomite; thinly bedded to ribbony, brown to brick or bright red, occasionally green shale, siltstone and sandstone to low-grade orthoquartzite; or brownish-weathered, thin-bedded, to strongly-laminated siliceous to calcareous phyllite intercalated with thin-bedded, locally lense-like to laminated dolomite and chert. Overlies Califon Member and underlies Wallkill Member, both of Leithsville. It is estimated that the Leithsville in NJ varies from 500 to 800 ft thick. Author assigns an Early Cambrian age to the Leithsville, based on the discovery of the index fossil HYOLITHELLUS MICANS by Markewicz (1964, unpublished).

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