Apollo Vent Field Site Details:

The Apollo vent field offers a rare glimpse into environments that could be windows into ocean systems elsewhere in our Solar System – on moons such as Enceladus and Europa. The Apollo vent field also offers an important comparison to the Sea Cliff hydrothermal site surveyed earlier in this expedition, which was first found in 1990 by Rona et al. and had not been visited in the last ~15 years. Both vent fields are different from the conventional “black smoker” hydrothermal systems, instead emitting clear fluids at temperatures around 300°C. This site was visited on June 6 and 7, 2019 at a depth of ~2700m.

Working with the SUBSEA team, Dr. Shannon Kobs Nawotniak of Idaho State University (ISU) Department of Geosciences, with PhD student Ashley Shields and MS student Angela Garcia, found Apollo Vent Field by closely examining the seafloor shape at Sea Cliff in high resolution bathymetry data. The ISU team used a 1m/pixel bathymetric map (currently under review) created with AUV by Dr. David Clague and his team at Monterey Bay Aquarium Research Institute. The ISU team considered the roughness of the ground, orientation of barely perceptible ridges, and position relative to the Gorda Ridge axis to determine potential hydrothermal sites. When the SUBSEA team finished other science objectives early during one ROV dive, the team was able to ground truth the proposed location, covering ~1500m2 approximately 1 km NE of Sea Cliff Vent Field. Data collected included temperature readings (300°C.), water samples for chemistry and microbiology, and ~0.5 m/pixel bathymetry and backscatter data.