Lines 3 and 4

Line three has been completed, and line four is in progress. The ship is now near the boundary between US and Bahamas waters, with continued great weather and glassy seas.

Photos and updates from Susie and Anastasiia

The view from the deck.

The team has been processing the seismic data from lines one and two, and they found that line two contains strong reflections 10-11 seconds down the trace that correspond to the Moho discontinuity (the boundary between the crust and the mantle, where the change from crustal to mantle media affects the velocity of a penetrating seismic wave).

The work boat was deployed again to check on the guns and streamers. The proximity of the guns to the streamers at this point in data collection was cause for concern, because in the event of rough weather, the instruments could knock into each other and sustain damage.

The technical crew heads back to the main ship, having completed necessary checks and adjustments to equipment positioning.

The recalibrated streamer-airgun equipment trails behind the Marcus Langseth.