Alden Pyrite Bed herein formally named for exposures along Spring Creek, between Crittenden Rd and U.S. Rte 20, Alden, NY. Important stratigraphic marker characterized by conspicuous pyritic nodules and phacopine trilobites in band of dark-gray calcareous shale. Incorrectly described by Fisher (1951) as a "marcasite horizon." Thickness ranges up to 80 cm. At type section unit occurs 15.5 m below the top of the Ledyard Member of the Ludlowville Formation and 7.3 m below the "Athol Springs bed" of Kloc (1983). Lies between dark-gray crumbly to blocky shales above and calcareous, medium-gray shales below. Unit extends from Cazenovia Creek in Erie Co to Jaycox Run in Livingston Co, a distance of 80 km. Age is Middle Devonian (Givetian).
Source: GNU records (USGS DDS-6; Reston GNULEX).
Alden pyrite interval occurs about 8 m above base of newly named Winspear submember [informal] of Ledyard Member of Ludlowville Formation. Unit is noted for its prized specimens of pyritized TORNOCERAS. Thickness about 1 m. (Name is credited to McCollum, 1980, SUNY PhD dissert.)
Notable exposures on Spring Creek, Alden Township, Erie Co., NY.
["Submember" not recognized as a formal stratigraphic rank term (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). Considered informal until formally published. The rank or lithologic term should not be capitalized.]
Source: Modified from GNU records (USGS DDS-6; Reston GNULEX).
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