Figure F14. Profiles of dissolved interstitial sulfate (SO42-) and barium (Ba2+) at (A) Sites 1248 and (B) 1244, showing different processes at these sites. At Site 1244, sulfate is present in the upper sediments and dissolved barium concentrations are near zero because of presumed barite (BaSO4) precipitation in this zone. At Site 1248, sulfate is absent in the upper sediments, so that dissolved barium may be released into the overlying water. The dashed line in A reflects higher barium concentration in situ, before freshwater is added to interstitial water by gas hydrate dissociation during sample recovery.

Figure F14. Profiles of dissolved interstitial sulfate (SO₄^2-) and barium (Ba²⁺) at (A) Sites 1248 and (B) 1244, showing different processes at these sites. At Site 1244, sulfate is present in the upper sediments and dissolved barium concentrations are near zero because of presumed barite (BaSO₄) precipitation in this zone. At Site 1248, sulfate is absent in the upper sediments, so that dissolved barium may be released into the overlying water. The dashed line in A reflects higher barium concentration in situ, before freshwater is added to interstitial water by gas hydrate dissociation during sample recovery.