Chromium Isotope System as a Tracer of Ocean and Atmosphere Redox

The stable chromium (Cr) isotope system has emerged over the past decade as a new tool to track changes in the amount of oxygen in earth''s ocean-atmosphere system. Much of the initial foundation for using Cr isotopes (δ53Cr) as a paleoredox proxy has required recent revision. However, the basic idea behind using Cr isotopes as redox tracers is straightforward—the largest isotope fractionations ar...