The combined nannofossil, foraminifer, diatom, and radiolarian biostratigraphy yielded 10 FO events and 11 LO events (Table T3) with age significance, using the shipboard stratigraphic framework (see the "Explanatory Notes" chapter). First occurrence events may have been estimated to be too shallow, based on limited sampling. The position of arrows in Figure F20 reflect the possibility that further work may extend these datums downhole. Last occurrence events may be too deep, again as a result of the limited sampling interval. The position of arrows in Figure F20 reflect the possibility that further work may extend these datums uphole. The LO of small nannofossils and diatoms that are prone to reworking have not been used to compile age-depth information.
The more reliable events, from the point of view of stratigraphic ranges established at the site and for the age-depth plot (Fig. F20), are listed in Table T3. While the FO of Globorotalia crassula in the base of Hole 1119C cannot be shown to be a true FO, the age of its FO (see "Biostratigraphy" in the "Explanatory Notes" chapter) affords useful constraint, hence its inclusion here. Equally, the LO of Discoaster asymmetricus in the base of Hole 1119C may be a result of reworking, but it still affords useful age constraint for the base of Hole 1119C.
Summarizing the data and taking into account the above uncertainties, the lower 200 m of Hole 1119C is Pliocene, and we find relatively moderate sedimentation rates, ~140 m/m.y. from the bottom of the hole to 300 mbsf. The sedimentation rate then decreases to ~100 m/m.y. from 300 to 250 mbsf in the lowermost Pleistocene. In the lower Pleistocene the rate is ~250 m/m.y. (250-120 mbsf), and middle to upper Pleistocene rates decline to ~125 m/m.y. (upper 120 mbsf). The biostratigraphic data do not indicate obvious stratigraphic disconformities, but resolution is limited using shipboard data. In particular, it must be observed that only the LO acme G. parallela (Event 4) defines the slower/faster/slower sedimentation rate motif above 300 mbsf. These varying sedimentation rates may be linked to the progradation and accretion of sediment drifts onto this margin.