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Bedrock Geology of the Montpelier Quadrangle, 2004

Detailed bedrock geologic mapping was conducted in the Montpelier Quadrangle during the summers of 2002-2003 by the VT Geological Survey (Kim, J. and Gale, M.) and
students from the University of Vermont (King, S. and Pascale, L.) and Middlebury College (Orsi, C.). Pascale, L., Orsi, C., Kim, J., and Klepeis, K. (UVM) conducted
additional analyses and presented the results as a poster at NEGSA in 2004. The table below includes figures and text from the poster by Pascale, et.al. . Click here to view the bedrock map of
the Montpelier quadrangle.

	Orthophoto mosaic of the Montpelier quadrangle with photolineaments identified through stereoscopic analysis. NNE trending photolinears are parallel to major lithologic contacts such as the Richardson Memorial Conact (RMC) - a major unconformity separating Pre-Silurian from Silurian-Devonian rocks. These photolinears appear as a series of distinct ridges and valleys/wetlands near the RMC that become progressively less abundant as one moves away from the RMC. A series of east-west trending stream valleys and ridges on the western slope of Long Meadow Hhill comprise a set of prominent photolinears that are parallel to a dominant fracture set in the area. Similarly, NW-SE trending ridges and valleys are found throughout the quadrangle and are likely related to a strong NW-SE trending fracture set. Some linear segments of the Winooski River are also thought tobe fracture-controlled.
	Comparison of photolineaments and bedrock structures.
	Comparison of water well yields east and west of the RMC.
	Orientation of dikes in Vermont.
	Correlation of fracture data in the Montpelier and Colchester quadrangles.
	Representative lithologies Metasedimentary and metaigneous rocks of the Montpelier Quadrangle are Pre-Silurian to the northwest (Moretown and Cram Hill Formations) and Silurian and Devonian to the southeast (Shaw Mountain, Northfield and Waits River Formations).
	3D TIN of the Montpelier quadrangle