Seismic-Refraction Profile across the Gulf of Maine

Abstract

On August 11, 1949, the USS MENTOR shot one partially reversed refraction profile across the northern Gulf of Maine, from a point southeast of Portland, eastward beyond Matinicus Rock (Fig. 1, shot 13). Three portable seismographs were set up at Falmouth, near Portland, Maine, on Mt. Desert Island, Maine, and at Crowell, Nova Scotia. The Crowell station was too far to the east to obtain clear ground arrivals from most of the shots. The failure of one of the engines of the MENTOR near shot 30 prevented the completion of the run and made it impossible to obtain a fix on the Lurcher Shoal buoy, which would have controlled the shot positions of the eastern half of the profile. As a result the eastern leg remained unreversed, and its results are unreliable.