Bedrock Geologic Map of the Hubbard Brook Experimental Forest, Grafton County, New Hampshire, USGS/OFR 00-45

Our mapping study was funded by the USGS Toxic Substances Hydrology Program and
was undertaken for the following reasons: 1) to ascertain whether the area
might have a greater number of mappable lithologic units than shown on Barton's
(1997) map, and to verify the stratigraphically higher formations shown on the
map; 2) to have sufficient data to draw geologic cross- sections through the
Mirror Lake research site; 3) to gather more data on brittle fracture
distribution and orientation; and 4) to assess the degree to which the
subsurface lithologies, ductile structures, and fractures observed at the two
Mirror Lake well fields correlate with the geology of the surrounding region.

The bedrock geology of the Hubbard Brook Experimental Forest, Grafton County,
New Hampshire is described in this report of new field investigation. The
database includes contacts of bedrock geologic units, faults, folds, and other
structural geologic information, as well as the base maps on which the mapped
geological features are registered. This report supersedes Barton (1997).

Data were originally collected in UTM coordinates, zone 19, NAD 1927, and
reprojected to geographic coordinates (Lat/Long), NAD 1983. The database is
accompanied by two large format color maps, a readme.txt file, and a
explanatory pamphlet.