|Geologic age||Middle Devonian|
Sedimentary > Clastic > Mudstone > Shale
Sedimentary > Carbonate > Limestone
|Comments||part of Hamilton Group 200-500 ft. (60-150 m). Secondary unit descriptions from USGS Lexicon website (ref. NY046) and references NY015, NY013, and NY021: Moscow Shale extended from western NY to western PA and in subsurface to northern WV and western MD (de Witt and others, 1993). Uppermost of five major formations in the Hamilton Group. In western NY, consists of gray to black shales, calcareous mudstones and thin limestone. Can be interpreted as a single major depositional sequence, representing 1.5 to 2.0 m.y. of geologic time and bounded above and below by angular unconformities. Lower portion according to authors "might be termed Portland Point subformation" and consists of the Tichenor, Deep Run, Menteth and Kashong Members. In the Cayuga Lake region and in Erie Co., members thin abruptly and merge into a thin limestone-rich interval previously termed the Portland Point Member. The upper, thicker portion of the Moscow consists of the Windom Shale Member in western NY and the Cooperstown Siltstone Member in central NY. In the Finger Lakes region another thin, silty, fossil-rich interval intervenes between the Kashong and the Windom and is here informally termed the "unnamed member." The unnamed member consists primarily of shales and thin concretionary limestone in western areas, but eastward can be subdivided into coarsening-upward mudstone to siltstone packages. The unnamed member extends from Hamilton in the Chenango Valley to just west of Bristol Valley where it is absent due to erosional truncation. It includes the informally named Barnes Gully bed at its base, MEGASTROPHIA beds, Curtice Road bed, and Geer Road bed. Between the Curtice Road and Geer Road beds is a 3-m-thick interval referred to as LONGISPINA-MUCROSPIRIFER shales. Age of the Moscow is Middle Devonian (Givetian) (Brett and Baird, 1994). Lowermost 50 m of the Moscow Formation in the Schoharie Creek and Valenti Road Sections is composed of gray mudstone interbedded with sandstone sets that vary in thickness from 1 cm to 1 m and contain small and medium-scale cross-strata and ripple marks. All strata is burrowed. The lowest 20 m is mudstone dominated and contains marine shelly fossils and quartz pebbles. The middle Moscow is composed of two 35-m-thick sandstone-dominated sequences, parts of which are exposed in this area. A mudstone-rich interval splits the two sandstone sequences. The upper Moscow is predominantly red and gray-green mudstone. The 130-m-thick lower to middle Moscow represents a regressive shoreline sequence on which three smaller-scale regressive sequences are superposed. In this area, the Moscow includes the lower Portland Point Member and the overlying Cooperstown Member. Overlies the Panther Mountain Formation and underlies the Gilboa Formation. Grades eastward into the Manorkill Formation. Age is Middle Devonian. Emphasis of article is on depositional environment. (Bridge and Willis, 1994).|
Fisher, D.W., Isachsen, Y.W., and Rickard, L.V., 1970, Geologic Map of New York State, consisting of 5 sheets: Niagara, Finger Lakes, Hudson-Mohawk, Adirondack, and Lower Hudson, New York State Museum and Science Service, Map and Chart Series No. 15, scale 1:250,000.
Brett, C.E. and Baird, G.C., 1994, Depositional sequences, cycles, and foreland basin dynamics in the late Middle Devonian (Givetian) of the Genesee Valley and western Finger Lakes region, IN Brett, C.E., and Scatterday, James, eds., Field trip guidebook: New York State Geological Association Guidebook, no. 66, 66th Annual Meeting, Rochester, NY, p. 505-585.
de Witt, Wallace, Jr., Roen, J.B. and Wallace, L.G., 1993, Stratigraphy of Devonian black shales and associated rocks in the Appalachian basin, IN Roen, J.B., and Kepferle, R.C., eds., Petroleum geology of the Devonian and Mississippian black shale of eastern North America: U.S. Geological Survey Bulletin, 1909-B, p. B1-B57.
Bridge, J.S. and Willis, B.J., 1994, Marine transgressions and regressions recorded in Middle Devonian shore-zone deposits of the Catskill clastic wedge: Geological Society of America Bulletin, v. 106, no. 11, p. 1440-1458.
USGS Geologic Names lexicon found at: http://ngmdb.usgs.gov/Geolex/
|Counties||Erie - Genesee - Livingston - Ontario - Wyoming|