High-resolution bolboformid and planktic foraminiferal distribution data from the upper Miocene section of ODP Site 1123, Chatham Rise, New Zealand, have been integrated with the magnetostratigraphic record from the same site to establish a magnetobiochronology based on the geomagnetic polarity time scale (GPTS-95). Although the upper Miocene sequence is adversely affected by dissolution, 33 bioevents are identified based on dissolution resistant taxa that are also found at DSDP Site 593 – an important biostratigraphic reference section for the Neogene in the Tasman Sea. A scatter plot based on the stratigraphic positions of shared bioevents at these oceanic sites approximates a linear line of correlation. The tight grouping of the biostratigraphic data around the line of correlation and the consistency of their stratigraphic order suggest most events are synchronous or nearly so, even though the sites are more than 1400km apart and associated with different water masses. This implies that even though the biostratigraphic construct is based on only two oceanic sites, it provides a robust late Miocene biochronostratigraphic framework for the temperate Southwest Pacific. Shared bolboformid events include the appearances and disappearances of Bolboforma subfragoris s.l. (11.56-10.61 Ma), B. gruetzmacheri (10.46-10.31 Ma), B. capsula (10.20-10.13 Ma), B. pentaspinosa (10.15-10.08 Ma), B. gracilireticulata s.l. (9.75-9.61 Ma), B. metzmacheri s.s. (lower occurrence interval 9.54-9.34 Ma, upper occurrence interval 9.01-8.78 Ma), B. metzmacheri ornata (8.45-8.28 Ma), B. praeintermedia (8.25-8.21 Ma), and abundance spikes associated with the uppermost B. subfragoris s.l. occurrence interval BBs-1123/D (10.61 Ma) and the lower B. metzmacheri s.s. occurrence interval BBm-1123/A (9.54 Ma). Shared planktic foraminiferal events include dextral coiling excursions in Globoconella miotumida (10.92-10.82 Ma and 9.62-9.42 Ma), the regional disappearance of Globoquadrina dehiscens (8.88 Ma), and the evolutionary appearances of Globoconella conomiozea (ca. 6.87 Ma), Globoconella mons (ca. 5.72 Ma), Globoconella sphericomiozea (ca. 5.53 Ma), Globoconella pliozea (ca. 5.39 Ma), Truncorotalia crassaformis (ca. 5.15 Ma), and Globoconella puncticulata (ca. 5.11 Ma).
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