Boomer seismic profiles, Charity Shoal structure, northeastern Lake Ontario

Single-channel seismic profiles were acquired over a 9-km2 area using a 100 J boomer seismic source (1-4 kHz; C-boom Ltd.) and 8-element hydrophone . Seismic profiles were collected along north-south and west-east lines. The survey navigation was recorded with an onboard D-GPS (± 0.5 m) and the seismic array positioned using a layback correction. The seismic processing flow included picking of water bottom first breaks, bandpass filtering (200-3500 Hz) and application of time-varying gain (TVG) in Vista 2D/3DTM software. In a final step, a zero-offset correction was applied to suppress water-bottom multiples using RadexplorerTM software . Depth scales on the seismic sections were estimated using a water column velocity of 1450 ms-1 and 1600 ms-1 for unconsolidated sediments above bedrock.