Description:
Descriptive terms for where sample was collected relative to the non-buoyant hydrothermal plume. Options include: "Above plume background" = in the water column above the well-defined non-buoyant plume; "Fluff" = the unconsolidated sediment layer suspended in seawater above sediment cores; "Near bottom background" = in the water column below the well-defined non-buoyant plume; "Plume-bottom" = within the well-defined non-buoyant plume; "Plume-middle" = within the well-defined non-buoyant plume; "Plume-top" = within the well-defined non-buoyant plume.