The upper depth limits of benthic foraminifers are utilized in determining paleobathymetry. Recent studies have shown that most species have an upper depth limit that indicates their shallowest occurrence. The lower limit of their depth range is of little value because of the high potential for downslope transport.
The compilation of paleobathymetric data (van Morkhoven et al., 1986) included several species that were identified in this study. The presence of Bulimina semicostata, Cibicidoides eocaenus, and Cibicidoides laurisae suggests a bathyal (400–1000 m) depositional environment for this sequence.
The range chart in the "Appendix" indicates the key species from each sample, their abundance, and their approximate ages.