Pictures of hydrothermal features in Palaeochori Bay. (a) White patches and a rocky reef as seen from cliffs overlooking the bay. (b) The physical appearance of the hydrothermal features was highly heterogeneous, ranging from patches of white to orange/yellow precipitates grading into non-pigmented background sediments. (c) The yellow and orange precipitates tended to form toward the center of the features where pore water temperatures were highest. (d) Gas flow from several vent mounds formed streams of bubbles in the water column. (e) Saline brine accumulated within a depression of a rocky reef. (f) Background sediments with no visible evidence for venting or microbial cover were used as control sites.