Figure F16. Patterns of carbonate sedimentation at the Congo group sites, based on shipboard results (data from Wefer, Berger, Richter, et al., 1998). A. Carbonate plotted as log of carbonate/noncarbonate ratio (standardized to mean = unity; std. = 0.25). B. Visual nannofossil abundance index, standardized. 8 = isotope stage (glacial).