Axial Seamount on the Juan de Fuca spreading center is the most magmatically robust volcano on the ridge, having erupted in 1998, 2011, and again April 24, 2015. It hosts numerous active hydrothermal fields and abundant sites of diffuse flow and it is one of the best-studied volcanoes along the global mid-ocean ridge spreading center. Axial Seamount magmas contain extremely high carbon dioxide concentrations supporting a robust subseafloor biosphere and it is the only site where there is greater than decade-long time-series studies documenting the evolution of microbial communities, and vent fluid chemistry and temperature following submarine volcanic eruptions. The summit of Axial Seamount was significantly transformed during the 2011 eruption with flows reaching nearly 3 km across the floor of the caldera, and > 8 km along the eastern fissure zone. The 2015 eruption on the northern rift system resulted in an ~ 7 km long, >400 ft thick flow. Three months after the eruption, the summit of the new, warm flow was covered by acres of microbial mats thriving off of volatile-rich, warm fluids circulating through the thick lava pile.
Questions to be addressed at Axial by the Cabled Array infrastructure include: 1) How do hydrothermal systems and associated microbial and macrofaunal communities change in response to magmatic, volcanic and seismic activity; 2) What is the flux of carbon from the seafloor to the hydrosphere; and 3) What is the nature of inflation and deflation events and their correlation with melt migration in the subsurface and release of volatiles into the vent systems? The myriad array of diverse data sets streaming live from sensors at the Axial Seamount will provide a strong foundation to study processes at within this dynamic system.
Location: 46°N, 130°W
Approximate Water Depth: 1,500 m at Summit
Description of Infrastructure:
5 Medium-Power J-Boxes: