Sedimentary velocities of the western North Atlantic margin

Abstract

Abstract During the 1954 cruise of the USS San Pablo and USS Rehoboth, 27 seismic refraction profiles were shot primarily to obtain detailed sedimentary data in the western North Atlantic. This work combined with later work, which also emphasized sedimentary data, provides 60 profiles in which gain and filter settings were adjusted to give coherent sedimentary arrivals. Good agreement was found among solutions obtained by several different methods for sediment thickness and velocity. Results indicate that velocity gradients are variable and are greatest near the liquid-sediment interface; wide-angle sedimentary arrivals in the deepsea profiles are reflections; refracted arrivals from the sediments are restricted to a zone shoreward of about halfway up to the continental rise.