The LoCH NESs project have been initiated!
The summer of 2017 a long-term temperature sensors, current meters, pressure gauge and ocean bottom seismometers (OBS) was deployed to look at how natural physical processes (e.g. ocean tides, micro-earthquakes) to constrain subsurface permeability structure beneath Loki’s Castle hydrothermal site.
The LoCH NESs (Loki’s Castle Hydrothermal iN-situ Experiments and Surveys) project focuses on understanding sub-surface physical conditions and fluid flow patterns and fluxes at Loki’s Castle vent site. We aim at using natural physical forcing processes (e.g. ocean tides, micro-earthquakes) to constrain subsurface permeability structure beneath Loki’s Castle hydrothermal site to ultimately inform estimates of heat, mass and chemical fluxes. In order to do so, we deployed last summer 2017 long-term temperature sensors, current meters, pressure gauge and ocean bottom seismometers (OBS) to i) examine effects of very different oceanic forcing regimes on the hydrothermal plumbing system and ii) explore dynamic changes in hydrothermal circulation and decipher feedbacks between fluid flow and sub-surface processes such as earthquakes. In addition, we carried out our first systematic imagery surveys of the area by performing consistent mapping with both high-resolution bathymetry and photomosaic imagery to give a geological context to physical and chemical fluid measurements and sampling and link our instrument network experiment with ecology and microbiology observations. Finally, we shot videos of venting fluid flow which will be processed and analyzed to estimate the rate and mass flux of venting. Those estimates could be coupled to temperature and surface area of hydrothermal outflow and geochemical measurements of hydrothermal fluids to calculate chemical fluxes of key species related to ore formation (e.g. Cu, Zn) as well as important carbon cycle components (e.g. CO2 and CH4).