Biogeochemical Exploration of the Pescadero Basin Vents

Abstract

In 2015, the deepest high-temperature hydrothermal vents in the Pacific Ocean (3,700 m) were discovered in a sediment-covered pull-apart basin along the Pescadero Transform Fault in the Gulf of California. Biological communities were observed thriving among the carbonate chimney structures (Figure 1; Goffredi et al., 2017). As a result of their striking contrast to other hydrothermal systems, the high- temperature, high-carbon Pescadero Basin vents provided the opportunity to examine the influence of tectonic setting on the nature of seafloor vent sites, the fundamental geochemical controls on biological colonization in the deep ocean, and the role of fluid venting on global-scale ocean chemistry and climate. In November 2017, with support from the Dalio Ocean Initiative, a multidisciplinary science team led by Woods Hole Oceanographic Institution scientists set out on E/V Nautilus to investigate this area of active venting.