Fig. 1: Overview of geochemical changes during the GOE.
From: Marine phosphorus and atmospheric oxygen were coupled during the Great Oxidation Event
a Hypothetical atmospheric oxygen level from this study, fossil images denote approximate first appearance of possible eukaryote and multi-cellular fossils. b Box plots (2nd to 3rd quartiles and median line of carbonate-bound iodate values, which is a proxy for dissolved oxygen in seawater from ref. 19. c Seawater sulphur isotope composition (yellow boxes from CAS, brown boxes from evaporite) modified after refs. 10, 34. d Box plots (2nd to 3rd quartiles and median line) of CAP data from this study, widths depict age uncertainties and tie points between two boxes reflect CAP from a single geological section with high (>3‰; darker shade box) and low (< 3‰; lighter shade box) δ13C values. Cw Carawine, Wi Wittenoom, Gd Gandarela, Tr Turee Creek, Es Espanola, Du Duitschland, Sa Saunders, Ff Fecho do Funil, Si Silverton, Mc Mcheka, Lk Lucknow, Ju Juderina (note Si, Mc and Ju have been grouped into one box plot with one median line (emboldened) for each formation), Fc Francevillian FC formation, La Lower Albanel, Ac Aquas Clara, Nf Nash Fork Formation, Wo Wooly Dolomite Formation, Al Aluminium River, Ba Balser Group. Arrow next to Cw box plot signifies age = ca. 2.6 billion years ago. e Idealised seawater inorganic carbon isotope profile and overview of redox proxies (green = reducing and red = oxidising conditions) after ref. 15. Vertical blue bars represent possible glacial intervals.
