Benthic Flow Meter V16

During the VISIONS'13 Expedition, two types of flow meters (CAT and Mosquito) were deployed at the summit of Southern Hydrate Ridge near the Einstein's Grotto active seep site - each instrument has specific ranges of flow that they measure. They will be recovered in 2014, providing year-long records of flow into and out of the sediment. Photo credit: OOI-NSF/UW/CSSF.

The benthic flow meter measures the velocity of fluids flowing into and out of the seafloor at methane seep sites, which is critical to determining the amount (flux) of methane, hydrogen sulfide, and other gases that are emitted into the overlying ocean. Methane is especially important because it is a greenhouse gas, and it and other gases support novel microbial communities that thrive in and on the seafloor at these sites (as well as in the overlying ocean).

During VISIONS '14, benthic flow meters were placed at the Axial Base node (MJ03A), on the deep (DP03A) and shallow (SF03A) profilers, at the International District 2 site (MJ03D) in the Axial Caldera, and at the Southern Hydrate Ridge summit (LJ01B). They were also placed at the Slope Base site (MJ01A), Slope Base deep (DP01A) and shallow (SF01A) profilers, the Endurance array, in the nearshore shelf benthic package (LJ01D), the offshore benthic package (LJ01C), and the offshore deep (DP01B) and shallow (SF01B) profilers.