Marine sedimentary rocks (lower Pliocene? and upper Miocene) (ORTm;0)

Massive, thick-bedded sandstone with minor interbeds of siltstone; local fossiliferous conglomerate lenses. Includes principally the Empire Formation of Baldwin (in Beaulieu and Hughes, 1975), originally considered of Pliocene age, but, on the basis of contained molluscan assemblage, now restricted to a late Miocene age (Addicott, 1983)

State	Oregon
Name	Marine sedimentary rocks (lower Pliocene? and upper Miocene)
Geologic age	Late Miocene to Early Pliocene
Original map label	Tm
Primary rock type	sandstone
Secondary rock type	siltstone
Other rock types	local fossiliferous conglomerate lenses
Lithologic constituents	Major Sedimentary > Clastic > Siltstone (Bed) Sedimentary > Clastic > Sandstone (Bed) Incidental Sedimentary > Clastic > Conglomerate (Bed)
Map references	Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000.
Unit references	Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000. Beaulieu, J.D., and Hughes, P.W., 1975, Environmental geology of western Coos and Douglas Counties, Oregon: Oregon Department of Geology and Mineral Industries Bulletin 87, 148 p. Addicott, W.O., 1983, Biostratigraphy of the marine Neogene sequence at Cape Blanco, southwestern Oregon: U.S. Geological Survey Professional Paper 774-G, p. G1-G20. [http://pubs.er.usgs.gov/publication/pp774G]
Geographic coverage	Coos