The age model for the 427-m-thick early Miocene to Pleistocene sequence cored at Site 1194 is biostratigraphically defined by nine calcareous nannofossil datums and five planktonic foraminifer datums (Table T6; Fig. F31) (see "Biostratigraphy and Paleoenvironments"). Strong core-top intensity anomalies corrupted the magnetic inclination record in the upper part of the section. In the lower part of the section, low core recovery prevents construction of a polarity sequence (see "Paleomagnetism"). Therefore, a magnetostratigraphy cannot be established at this site, and the biostratigraphic control points are used to construct the shipboard age model for Site 1194 (Fig. F31).
The low-resolution biostratigraphy in the early to middle Miocene Megasequence C (lithologic Units III to V) can be represented by one straight age-depth segment with an average sedimentation rate of 31 m/m.y. (Fig. F31). A hardground that caps lithologic Unit III at 117 mbsf contains a late middle to late Miocene hiatus, which lasted from ~11.8 to ~7.7 Ma. The late Miocene to Pliocene (8-2.6 Ma) is represented by lithologic Unit II, which is correlative with Megasequence D, a hemipelagic section with frequent gravity flow deposits. A significant hiatus or condensed section is indicated at the lithologic Unit I/II boundary (3.8 mbsf) and may have lasted as long as 2.5 to ~0.8 Ma.
Age picks for lithologic and seismic unit boundaries are summarized in Table T7.