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Figure F11. Ages of seismic sequence boundaries and correlation with the oxygen isotopic record, sedimentation rates, and Alpine Fault convergence rates. Two isotopic records are shown, both from Billups and Schrag (2002): (1) unmodified benthic foraminiferal δ¹⁸O record from ODP Site 747 and (2) the same record corrected using Mg/Ca thermometry to remove the temperature effect and yield the δ¹⁸O of seawater (¹⁸O_sw), predominantly a response to ice volume and therefore an enhanced proxy for global sea level. The δ¹⁸O_sw record correlates better both with individual seismic sequences and longer term progradational and aggradational trends, as well as with the Haq et al. (1987) eustatic curve (also shown, recalibrated to the timescale of Berggren et al., 1995). This suggests eustatic control of sequence timing. Cooling events Mi2, Mi3a, Mi3b, Mi4, and Mi5, derived from the oxygen isotope records from DSDP Site 608 and ODP Sites 703 and 704 (Miller et al., 1996), are shown. Average sedimentation rates are calculated from estimated sequence volumes. The perpendicular component of motion at the Alpine Fault plate boundary was calculated using the method of Cande and Stock (2004). Finite rotations for Australia-Pacific motion were determined for four chrons (2A, 2.58 Ma; 3A, 6.04 Ma; 5, 11.53 Ma; 6, 20.13 Ma; ages are those of Cande and Kent, 1995). The increase in both sedimentation and convergence rates over the last 5–8 m.y. correlate well. The early phase of high sedimentation rates (S2–S4) may reflect global processes. See "2. Constrain the erosion history of the Southern Alps" in "Secondary Objectives" for further discussion. A summary of South Island tectonic and volcanic events is also shown.

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