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Geologic Unit: Dalton
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Map showing publication footprint
  • Usage in publication:
    • Dalton phyllite*
  • Modifications:
    • [First used]
  • Dominant lithology:
    • Phyllite
  • AAPG geologic province:
    • New England province
Publication:

Emerson, B.K., 1892, [Hawley sheet, Massachusetts]: U.S. Geological Survey, unpublished report, __., [Proof sheets of geologic maps and text intended for a geologic folio but never completed and published in that form, although cited in USGS Bull. 191, 1902, USGS Mon. 29, p. 18, 1898, and USGS Bull. 159, 1899.]


Summary:

[Dalton phyllite is shown as underlying Hoosac schist and as overlying [underlying] Cheshire quartzite which rests on Becket gneiss.]

Source: US geologic names lexicon (USGS Bull. 896, p. 978-568).


Map showing publication footprint
  • Usage in publication:
    • Dalton phyllite*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • New England province
Publication:

Emerson, B.K., 1899, The geology of eastern Berkshire County, Massachusetts: U.S. Geological Survey Bulletin, 159, 139 p., (incl. geologic map, scale 1:165,287)


Summary:

Included the Dalton in Cheshire quartzite as defined and mapped. His map included Dalton type locality.

Source: US geologic names lexicon (USGS Bull. 896, p. 978-568).


Map showing publication footprint
  • Usage in publication:
    • Dalton formation*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • New England province
Publication:

Emerson, B.K., 1917, Geology of Massachusetts and Rhode Island: U.S. Geological Survey Bulletin, 597, 289 p.


Summary:

Pg. 32-34 and map. Dalton formation. At some places in western Massachusetts the lowermost Cambrian strata consist of gneissoid conglomerate having maximum thickness of 600 or 700 feet. The pebbles are chiefly quartz (black, blue, and commonly white) but a few are feldspar or gneiss [between 5 and 100 mm long]. This conglomerate can be traced for miles across Hinsdale and into Washington [western Massachusetts]. Is best exposed at site of former Dalton clubhouse, on high hill south of Dalton Station, in open pasture farther south and on southeast to new lookout tower. The conglomerate was originally feldspathic and has generally changed to a thin fissile light-colored gneiss or schist in which the muscovite is generally a greasy hydrated sericite. Grades into overlying Cheshire quartzite. Rests unconformably on Becket gneiss. Age is Early Cambrian. [According to personal communication of B.K. Emerson, the Dalton formation of 1917 publication is same as Dalton phyllite of 1892 Hawley sheet.]

Source: US geologic names lexicon (USGS Bull. 896, p. 568); supplemental information from GNU records (USGS DDS-6; Reston GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Dalton formation
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • New England province
Publication:

Osberg, P.H., 1952, The Green Mountain anticlinorium in the vicinity of Rochester and East Middlebury, Vermont: Vermont Geological Survey Bulletin, no. 5, 127 p.


Summary:

Correlation chart for Vermont shows Dalton formation in southwestern part of the State below Cheshire quartzite. Age is Early Cambrian.

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


Map showing publication footprint
  • Usage in publication:
    • Dalton Formation*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • New England province

Map showing publication footprint
  • Usage in publication:
    • Dalton Formation*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • New England province

Map showing publication footprint
  • Usage in publication:
    • Dalton Formation*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • New England province
Publication:

Ratcliffe, N.M., and Harwood, D.S., 1975, Blastomylonites associated with recumbent folds and overthrusts at the western edge of the Berkshire massif, Connecticut and Massachusetts; a preliminary report, IN Tectonic studies of the Berkshire Massif, western Massachusetts, Connecticut, and Vermont: U.S. Geological Survey Professional Paper, 888-A, p. A1-A19.


Summary:

Geographically extended into northernmost Connecticut on map (fig. 1 of report). Mapped undivided with Cheshire Quartzite. Age is Early Cambrian and late Precambrian(?).
[GNU staff remark (1990): Harwood's 1979 map of the South Sandisfield quadrangle (USGS GQ-1519) confirms presence only of Dalton in Connecticut; no Cheshire mapped in Connecticut in that quadrangle which covers same area as this paper.]

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


Map showing publication footprint
  • Usage in publication:
    • Dalton Formation*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • New England province

Map showing publication footprint
  • Usage in publication:
    • Dalton Formation*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • New England province
Publication:

Zen, E-an (editor), Goldsmith, Richard (compiler), Ratcliffe, N.M. (compiler), Robinson, Peter (compiler), Stanley, R.S. (compiler), Hatch, N.L., Jr., Shride, A.F., Weed, E.G.A., and Wones, D.R., 1983, Bedrock geologic map of Massachusetts: U.S. Geological Survey [State Geologic Map], 3 sheets, scale 1:250,000


Summary:

Used as Dalton Formation of Proterozoic Z and Early Cambrian age. Consists of one undivided formation and five informal members distinguished lithologically.

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


Map showing publication footprint
  • Usage in publication:
    • Dalton Formation*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • New England province
Publication:

Thompson, J.B., Jr., 1990, An introduction to the geology and Paleozoic history of the Glens Falls 1 degree x 2 degrees quadrangle, New York, Vermont, and New Hampshire, IN Slack, J.F., ed., Summary results of the Glens Falls CUSMAP project, New York, Vermont, and New Hampshire: U.S. Geological Survey Bulletin, 1887-A, p. A1-A13.


Summary:

Stratigraphic succession in Middlebury synclinorium in north-central part of Glens Falls quadrangle consists of (ascending) Late Proterozoic Dalton Formation and Pinnacle Formation, Lower Cambrian Cheshire Quartzite, Lower and Middle Cambrian dolomites (Rutland Dolomite, Dunham Dolomite as used by Cady (1945), Winooski Dolomite) with minor quartzite (Monkton Formation), and Upper Cambrian Danby Formation. Middlebury synclinorium is considered a parautochthonous shelf sequence.

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


Map showing publication footprint
  • Usage in publication:
    • Dalton Formation*
  • Modifications:
    • Revised
  • AAPG geologic province:
    • New England province
Publication:

Burton, W.C., 1993, Bedrock geologic map of the Sunderland quadrangle, Bennington and Windham Counties, Vermont: U.S. Geological Survey Miscellaneous Field Studies Map, MF-2224, 1 sheet, scale 1:24,000


Summary:

Rocks previously mapped as Mendon Formation in this area are here called Dalton Formation following the usage on the Vermont State geologic map by Doll and others (1961).

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


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