Lead in bottom sediments, nodules, and sulfides from the Black Sea

A study of lead distribution in recent, ancient Black Sea and Neweuxinian bottom sediment shows similar vertical distributions of the element in the oxygen and hydrogen sulfide zones of the sea; i.e. hydrogen sulfide contamination does not affect lead contents in bottom sediments of the sea. Lead distribution in sediment mass of the Black Sea reflects dependence of accumulation of the element on the hydrodynamic regime of the sea and forms of its migration. It is noted that absence of lead accumulation in Black Sea nodules results from specific nodule formation and from geochemical activity of the element. A large role of diagenetic sulfide formation in lead geochemistry is shown. Degree of lead accumulation in iron sulfides depends on conditions of sedimentation and on physical and chemical parameters in the sea.