Figure 2.

Sections with local palaeoredox proxy data (map modified after Li et al., 2013). Yellow stars indicate available iron speciation data, brown stars indicate available complimentary data of redox (i.e., RSE and REE). Numbers 1–30 relate to major redox studies. 1, Fike et al. (2006); 2, Canfield et al. (2007); 3, Canfield et al. (2008); 4, Shen et al. (2008); 5, Li et al. (2010); 6, Dahl et al. (2010); 7, Shen, Xiao, Zhou, Kaufman, and Yuan (2010); 8, Schroder and Grotzinger (2007); 9, Shen et al. (2011); 10, Sahoo et al. (2012); 11, Wang et al. (2012); 12, Johnston et al. (2012); 13, Och et al. (2013); 14, Frei et al. (2013); 15, Johnston et al. (2013); 16, Fan et al. (2014); 17, Feng et al. (2014); 18, Yuan et al. (2014); 19, Spangenberg, Bagnoud‐Velásquez, Boggiani, and Gaucher (2014); 20, Li, Planavsky, et al. (2015); 21, Kendall et al. (2015); 22, Och et al. (2015); 23, Wood et al. (2015); 24, Sperling, Wolock, et al., 2015; 25, Sperling, Carbone et al. (2015); 26, Osburn, Owens, Bergmann, Lyons, and Grotzinger (2015); 27, Kurzweil et al. (2015); 28, Han and Fan (2015); 29, Jin et al. (2016); 30, Sahoo et al. (2016); 31, Tostevin, Wood, et al., (2016) [Colour figure can be viewed at wileyonlinelibrary.com]