Mapping bedrock surface contours using the horizontal-to-vertical spectral ratio (HVSR) method near the middle quarter srea, Woodbury, Connecticut

Craig J. Brown; Emily B. Voytek; John W. Lane; Janet Radway Stone

doi:10.3133/ofr20131028

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Mapping bedrock surface contours using the horizontal-to-vertical spectral ratio (HVSR) method near the middle quarter srea, Woodbury, Connecticut

Craig J. Brown·Emily B. Voytek·John W. Lane·Janet Radway Stone

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Abstract

The bedrock surface contours in Woodbury, Connecticut, were determined downgradient of a commercial zone known as the Middle Quarter area (MQA) using the novel, noninvasive horizontal-to-vertical (H/V) spectral ratio (HVSR) passive seismic geophysical method. Boreholes and monitoring wells had been drilled in this area to characterize the shallow subsurface to within 20 feet (ft) of the land surface, but little was known about the deep subsurface, including sediment thicknesses and depths to bedrock (Starn and Brown, 2007; Brown and others, 2009). Improved information on the altitude of the bedrock surface and its spatial variation was needed for assessment and remediation of chlorinated solvents that have contaminated the overlying glacial aquifer that supplies water to wells in the area.

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Source-reported bounding extent: 41.508527° to 41.612696° latitude; -73.267336° to -73.145155° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Craig J. Brown, Emily B. Voytek, John W. Lane, Janet Radway Stone. 2013. Mapping bedrock surface contours using the horizontal-to-vertical spectral ratio (HVSR) method near the middle quarter srea, Woodbury, Connecticut. https://doi.org/10.3133/ofr20131028

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