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Map showing publication footprint
  • Usage in publication:
    • Greenback Member
  • Modifications:
    • Named
  • Dominant lithology:
    • Silt
  • AAPG geologic province:
    • Cascades province
Publication:

Balster, C.A., and Parsons, R.B., 1969, Late Pleistocene stratigraphy, southern Willamette Valley, Oregon: Northwest Science, v. 43, no. 3, p. 116-129.


Summary:

Named as uppermost member (of 4) of Willamette Formation [Silt]. Type locality designated as exposures from Greenback School, NE/4 SE/4 sec.4 T13S R4W, south 13 km to Irish Bend on Willamette River, Linn Co, OR. Consists of gray silt with iron-manganese concretions. Overlies Malpass, Irish Bend, or Wyatt Member (all new) of Willamette Silt. Age given as late Pleistocene.

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


For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).

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