Figure 21. Downhole abundance fluctuations of opaline (diatoms and radiolarians) and calcareous (benthic foraminifers and nannofossils) microfossils at Hole 1081A. The abundance definitions for diatoms, radiolarians, and calcareous nannofossils are given in the "Biostratigraphy" section, "Explanatory Notes" chapter (this volume). The abundance definition of benthic foraminifers is given in the caption of Figure 22.