The proposed relocation of the Concord-Westminster Highway, Route 2, in Lancaster, Mass., requires a long, deep cut between stations 138 and 155. A preliminary seismic survey was made of the site in October 1949. At that time five transverses were made along the base-line, and three transverse to it. This work showed an anomalous situation in the vicinity of shot point E. In order to obtain the required additional data to resolve these anomalies, four more seismic transverses were made in November 1949. Two of these were run along the base-line between station 138+52 and station 145+12 in such a way as to yield, in conjugation with the preliminary survey, depth data of a 660-foot transverse. One of the primary functions of this long line was to obtain a reliable bedrock velocity. The other two transverses were transverse to the long transverse. This report comprises all of the seismic and geologic work performed at this site.
The work was done as a part of a cooperative program of the Massachusetts Department of Public Works and the United States Geological Survey.