Figure F13. Hydrothermal circulation model sketched along an east-west cross-section looking north. Hydrothermal fluids flow from basalt basement through a fault conduit. As the fluids reach the surface they enter the permeable sandy turbidite units and conductively cool. Sulfide minerals precipitate within the sedimentary pore structure. In the less permeable hemipelagic mud- and clay-rich layers, hydrothermal fluids are focused through fractures.