Bottom Pressure Tilt at the International Field
A bottom pressure-tilt instrument is installed at the summit of Axial Seamount in the International District hydrothermal field. This instrument measures the rise and fall of the seafloor due to melt migration in the subsurface. Currently, the seafloor is rising and this is believed to reflect the influx of magma into the core of the volcano.The instrument rests on a frozen lava flow - called a sheet flow. The small black marble in the yellow plate at the instrument base indicates that the platform it level. Photo credit: NSF-OOI/UW/CSSF; Dive R1723; V14.