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doi:10.2204/iodp.proc.314315316.210.2012

Conclusions

In conclusion, this study presents the range chart of Pliocene–Pleistocene age-diagnostic nannofossils and provides better resolved nannofossil datums and zones for Site C0004 and Hole C0008A.

At Site C0004, Unit II and III prism sediments in the megasplay fault system are of early–middle Pliocene age (Zones NN16, NN15–NN14, and NN13); sediments above and below the prism are Pleistocene age (upper Pleistocene sediments lie above the prism and lower Pleistocene sediments below it). In Hole C0008A, the majority of Unit I is of Pleistocene age (Zones NN21 and NN19), and the lowest part of Unit I and Unit II are of late Pliocene age (Zones NN18, NN17, and NN16).

Biostratigraphic correlation between Site C0004 and Hole C0008A suggests that most of Unit II at Site C0004 comprises faulted sediments and that faulting probably occurred roughly between 1.60 and 1.56 m.y. The faulted interval can subdivided into two parts: an upper part with normal zone sequence and a lower part characterized by common faults and age reversals. These two zones may correspond to uplift and subsequent disruption of the accretionary prism, similar to the interpretation of Strasser et al. (2009).