HIGH CO2 CONTENT IN HYDROTHERMAL VENT WATER AT THE SNAKE PIT AREA, MID-ATLANTIC RIDGE

Carbon dioxide contents and partial pressures were measured during the MAR 93 cruise on several water samples collected from black smoker ch imneys and around mussels and shrimps at the Snake Pit (MARK) vent fie ld (Mid-Atlantic Ridge). High end-member values for total CO2 (10.63 m mol l(-1)) and CO2 partial pressure (335 Ton directly measured at 33 d egrees C; 1 Ton = 0.133 kPa) were recorded for black smokers samples. Water sampled in close proximity of organisms was found moderately but significantly enriched in carbon dioxide.