A DEPTH COINCIDENCE BETWEEN THE LANTHANIDE TETRAD EFFECT MAXIMUM AND THE OXIC ANOXIC INTERFACE AT THE CARIACO TRENCH OFF THE VENEZUELAN COAST/

Under the highly stagnant condition at the Cariaco Trench, the lanthan ide tetrad effect takes place abruptly within an extremely narrow dept h range. The lanthanide tetrad effect maximum at the Cariaco Trench is observed at 256 m coinciding with its oxic/anoxic interface at 280 m. It is also interesting that the maximum value of the lanthanide tetra d effect at this trench is substantially the same as that in ordinary open ocean.