Bedrock geologic map of the Bellows Falls 7.5- x 15-minute quadrangle, Windham and Windsor Counties, Vermont, and Sullivan and Cheshire Counties, New Hampshire

Arthur J. Merschat; Gregory J. Walsh; Peter M. Valley; Ryan J. McAleer; Thomas R. Armstrong

doi:10.3133/sim3535

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Bedrock geologic map of the Bellows Falls 7.5- x 15-minute quadrangle, Windham and Windsor Counties, Vermont, and Sullivan and Cheshire Counties, New Hampshire

Arthur J. Merschat·Gregory J. Walsh·Peter M. Valley·Ryan J. McAleer·Thomas R. Armstrong

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Abstract

Introduction The bedrock geology of the Bellows Falls 7.5- x 15-minute quadrangle, Vermont and New Hampshire, consists of polydeformed Ordovician to Devonian metasedimentary, metavolcanic, and metaplutonic rocks of the Connecticut Valley trough, Bronson Hill anticlinorium (or Bronson Hill terrane), and the Central Maine terrane. Previous work in this area includes a 1:62,500-scale published map and text (1946), State geologic maps of New Hampshire (1997) and Vermont (2011), and various maps and reports presented largely as parts of field trip guidebooks. A provisional open-file map of the geology of the Vermont part of the Bellows Falls 7.5- x 15-minute quadrangle, completed in 1997, is incorporated and revised on this map based on additional fieldwork. This study recognizes three major structural levels from west to east and from lowest to highest: (1) autochthonous rocks of the Connecticut Valley trough; (2) allochthonous rocks of the New Hampshire sequence and Bronson Hill arc in the Monroe thrust sheet (or nappe), including the Skitchewaug nappe; and (3) allochthonous rocks of the Fall Mountain thrust sheet or nappe.

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Scientific Investigations Map Report

Source-reported bounding extent: 43.125° to 43.25° latitude; -72.5° to -72.25° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Arthur J. Merschat, Gregory J. Walsh, Peter M. Valley, Ryan J. McAleer, Thomas R. Armstrong. 2025-05-21. Bedrock geologic map of the Bellows Falls 7.5- x 15-minute quadrangle, Windham and Windsor Counties, Vermont, and Sullivan and Cheshire Counties, New Hampshire. https://doi.org/10.3133/sim3535

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United STates place Bellows Falls 7.5- x 15-minute quadrangle place Cheshire County, Sullivan County, Windham County, Windsor County place New Hampshire, Vermont place Report subject Scientific Investigations Map subject

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