Sediment slides and turbidity currents on the Laurentian Fan: sidescan sonar investigations near the epicenter of the 1929 Grand Banks earthquake.

At the head of the Eastern Valley of the Laurentian Fan, west of the epicenter, arcuate slide scars cut undisturbed upper-slope sediment and lead downslope to a lineated erosional seabed. At a water depth of about 1600m, this erosional seabed passes into extensive fields of 100m-wavelength gravel waves situated on the broad, irregular valley floor. Timing of cable breaks downfan suggests that flow velocities were sufficient to rework gravel deposits into large bedforms during waning flow stages over elevated areas of the valley floor.-from Authors