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Bedrock geologic and joint trend map of the Pinardville quadrangle, Hillsborough County, New Hampshire

Open-File Report 2013-1027

By:
and
DOI: 10.3133/ofr20131027

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Abstract

The bedrock geology of the Pinardville quadrangle includes the Massabesic Gneiss Complex, exposed in the core of a regional northeast-trending anticlinorium, and highly deformed metasedimentary rocks of the Rangeley Formation, exposed along the northwest limb of the anticlinorium. Both formations were subjected to high-grade metamorphism and partial melting: the Rangeley during the middle Paleozoic Acadian orogeny, and the Massabesic Gneiss Complex during both the Acadian and the late Paleozoic Alleghanian orogeny. Granitoids produced during these orogenies range in age from Devonian (Spaulding Tonalite) to Permian (granite at Damon Pond), each with associated pegmatite. In the latest Paleozoic the Massabesic Gneiss Complex was uplifted with respect to the Rangeley Formation along the ductile Powder Hill fault, which also had a left-lateral component. Uplift continued into the early Mesozoic, producing the 2-kilometer-wide Campbell Hill fault zone, which is marked by northwest-dipping normal faults and dilational map-scale quartz bodies. Rare, undeformed Jurassic diabase dikes cut all older lithologies and structures. A second map is a compilation of joint orientations measured at all outcrops in the quadrangle. There is a great diversity of strike trends, with northeast perhaps being the most predominant.

Study Area

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Bedrock geologic and joint trend map of the Pinardville quadrangle, Hillsborough County, New Hampshire
Series title:
Open-File Report
Series number:
2013-1027
DOI:
10.3133/ofr20131027
Year Published:
2013
Language:
English
Publisher:
U.S. Geological Survey
Publisher location:
Reston, VA
Contributing office(s):
Eastern Geology and Paleoclimate Science Center
Description:
1 Plate: 47.20 x 34.29 inches; Downloads directory
Country:
United States
State:
New Hampshire
County:
Hillsborough County
Other Geospatial:
Pinardville Quadrangle
Datum:
1983 North American Datum
Scale:
24000
Online Only (Y/N):
Y