Research project: Hydrothermal vents on the world’s deepest seafloor spreading centre
Currently Active:
Yes
In 2010 Cruise JC044 discovered two unique hydrothermal vents at the ultra-slow spreading Mid-Cayman Rise. One, situated at 4960 mbsl, is the deepest yet discovered, and the other, at 2300 mbsl, is located on the Mount-Dent oceanic core complex will provide new insight into off-axis fluid flow.
Project Overview
The deep site, called ‘Beebe', is a high temperature black smoker system and shows evidence for super-critical phase separation. The off axis site, called ‘Von Damm', vents shimmering fluid and is thought to be a new type of vent site given its chimney and mound composition.
Why study the Mid-Cayman Rise?
Beebe site:
Can be used as a natural lab to investigate the effects of supercriticality on vent fluid composition
The increased seawater pressure could affect mound preservation/morphology/composition
Potential for further hydrothermal sites at this depth
Von Damm site:
Discovery of further off-axis venting offsets models for oceanic circulation
Changes in measured heat flux at mid-ocean ridges
Potential for fluid flow brought about by oceanic core complex development
Scientific aims and outcomes
Investigate composition of mounds, chimneys and host rocks - give an overview of fluid-rock interaction conditions
Develop detailed geological maps and investigate fluid flow controls from ROV video and AUV bathymetry
Determine ages of both systems
Compare with other known, similar vent sites, both active and in the geological record