Figure 7: Plots of ln EA versus ln L from with serial deletions of abundance biozones during the accumulation procedure. Dashed lines indicate the positions at which abundance biozone (AB) boundaries are identified. (a) Grouping of the first 4 samples as AB1. (b) Following deletion of the first four samples, grouping of the next two as AB2. Figures 7(c) through 7(i) continue this sequential procedure until all samples are accounted for.