MNO2/MN2+ SYSTEM AS THE POTENTIAL-GOVERNING SYSTEM IN EH MEASUREMENTS ON STRONGLY OXIDIZED PELAGIC BOTTOM SEDIMENTS

Abstract

Study of the redox state of pelagic bottom sediments (red clays) is important to an understanding of the evolution of iron-manganese nodules in the ocean. There is now a large body of direct potentiometric measurements of these sediments, made with platinum indicator electrodes. But there has been no discussion of the nature of the potential-governing system or of the reason for the difficulty of measurements (slow attainment of steady-state potential, and poor reproducibility of results). In the present paper the authors describe investigations made during the 8th cruise of the R/V Akademik Aleksandr Vinogradov in the Central Pacific Ocean during 1986.