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  • Usage in publication:
    • Megunticook Formation
  • Modifications:
    • Overview
  • Dominant lithology:
    • Schist
    • Granulite
  • AAPG geologic province:
    • New England province
Publication:

Osberg, P.H., and Berry, H.N., IV, 1991, Stratigraphy of lithotectonic belts west of Penobscot Bay, Maine, IN Ludman, Allan, ed., Geology of the coastal lithotectonic block and neighboring terranes, eastern Maine and southern New Brunswick: New England Intercollegiate Geological Conference Guidebook, 83rd annual meeting, Princeton, ME, September 27-28, 1991, p. 358-373.


Summary:

Simplified stratigraphic column for the Islesboro-Rockport belt in eastern ME shows (ascending) Precambrian rocks of Gilkey Harbor, Islesboro Formation, Coombs Limestone, Cambrian Rockport Quartzite and Megunticook(?) Formation. Some question as to whether unit is correctly identified in this area and correlates with the type Megunticook in the St. Croix belt where unit consists of gray quartz-muscovite-biotite-andalusite-garnet schist and sparse beds of quartz-plagioclase-biotite granulite. Battie Quartzite forms a distinctive lens within the Megunticook. These rocks do not correlate with the Kendall Mountain and Woodland Formations in the Calais area, as previously thought. In St. Croix belt, underlies Penobscot Formation and unconformably overlies lower part of Jam Brook Formation.

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


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