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Map showing publication footprint
  • Usage in publication:
    • Beaver Brook Member*
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Gneiss
    • Amphibolite
    • Schist
  • AAPG geologic province:
    • New England province
Publication:

Bell, K.G., and Alvord, D.C., 1976, Pre-Silurian stratigraphy of northeastern Massachusetts, IN Page, L.R., ed., Contributions to the stratigraphy of New England: Geological Society of America Memoir, 148, p. 179-216.


Summary:

Pg. 184-185, 208, App. 1 (in pocket). Beaver Brook Member of Nashoba Formation. Medium-gray sillimanitic biotite gneiss, amphibolite, schist, and calc-silicate rocks. Medium-grained, stratified, relict sedimentary structure. Thickness 1,580 m. Is uppermost member of the Nashoba. Overlies Long Pond Gneiss Member (new) of Nashoba Formation; underlies Tadmuck Brook Schist (new). Age is pre-Silurian.
Type locality: area bounded on northeast by Mill Road, on southeast by Foster Street in town of Littleton, on southwest by Old Turnpike-Littleton County Road in towns of Boxborough and Harvard, and on northwest by southeast foot of Oak Hill in towns of Harvard and Littleton, Middlesex Co., central MA; Ayer, Hudson, and Westford quadrangles, Middlesex Co., central MA. Origin of name not stated.

Source: US geologic names lexicon (USGS Bull. 1520, p. 9-10).


Map showing publication footprint
  • Usage in publication:
    • Beaver Brook Member*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • New England province
Publication:

Goldsmith, Richard, 1980, Stratigraphic names in the New London area, southeastern Connecticut; a revision, IN Sohl, N.F., and Wright, W.B., Changes in stratigraphic nomenclature by the U.S. Geological Survey, 1979: U.S. Geological Survey Bulletin, 1502-A, p. A91-A103.


Summary:

Age of Nashoba Formation changed from pre-Silurian to Proterozoic or Ordovician.

Source: GNU records (USGS DDS-6; Reston 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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