Fig. 8

Summary of geochronological data for the Anno Formation. a Tephra marker beds and slump bed names. Red tephra marker beds indicate widespread tephra. b Lithological column for the study area. c Age constraints from previous studies. Vertical arrows indicate the calcareous nannofossil data from Kameo and Sekine (2013). Red triangles indicate radiometric ages for tephra marker beds from previous studies as follows: *1 An85 from Ueki et al. (2018), *2 An77 from Makinouchi et al. (1983), and *3 An73 and An49 from Tokuhashi et al. (2000). d Polarities based on the vertual geomagnetic pole (VGP) latitudes shown in Fig. 7d. Colored squares indicate polarities (black: normal; white: reversed; gray: intermediate). e Variation of the VGP latiutde shown in Fig. 7d. f Oxygen isotope stratigraphy of the Anno Formation. g Age model based on correlating the oxygen isotope profile of the Anno Formation with the LR04 benthic stack from Lisiecki and Raymo (2005). Letters and numbers represent marine isotope stages (MISs) from the LR04 benthic stack, and colors indicate the following: red: interglacial; blue: glacial; gray: stages not observed in this study. h Geomagnetic Polarity Time Scale 2012 from Ogg (2012). i Pliocene subepoch based on Hilgen et al. (2012). Darker shading represents polarity reversal horizons. Light shading represents the hiatus of the Sak slump bed. Dashed gray boxes are shown in Fig. 9. VPDB Vienna Pee Dee Belemnite