Expedition log by MBARI Senior Scientist Aaron Micallef

When we reached our working area, we were still met with ice cover, which forced us to adapt our plans. Instead of deploying all the instruments we had hoped for, we began with multibeam mapping to chart the seafloor, sub-bottom profiling to peer beneath the sediments, and a series of gravity cores and multi-cores to recover samples. From these cores, we extracted porewater for geochemical analyses, and in one gravity core, we even found ice embedded within the sediment.

A real highlight came with the first autonomous underwater vehicle (AUV) survey at a site called Garry Knolls. The AUV delivered gorgeous sub-meter resolution bathymetry, capturing details of the seafloor landscape that are difficult to resolve from a ship. These new data not only provide a fresh perspective on the subtle features and processes shaping this part of the continental shelf, but will also be compared with surveys carried out decades ago to see how the seafloor may have changed over time.

In parallel, we are acquiring controlled-source electromagnetic (CSEM) data to determine the extent and distribution of sub-sea permafrost, adding a new dimension to our investigation.

The team is energized by the flow of new data and the sense of discovery that comes with each successful deployment. At the same time, the persistent ice and the tight schedule add a note of anxiety. There is always the question of whether we will be able to accomplish much of what we set out to do. For now, though, the combination of technical achievements, teamwork, and determination keeps spirits high as we push further into the expedition.