Fig. 24
From: Shallow structure and late quaternary slip rate of the Osaka Bay fault, western Japan
a Depositional curves at representative sites along Lines 1–11 (location shown in Figs. 1–10, 13–17, 19) and at Site OB-1 offshore Kobe (Masuda et al. 2000), plotted with the relative sea-level curve derived from ostracod paleo-depth assemblage from a borehole at the Osaka Basin, Kitatsumori (Miyahara et al. 1999; Masuda et al. 2000; Masuda and Itomoto 2015). Elevation is measured from present sea-level. Note that the middle sequence of the Holocene alluvium (Unit A1’) is distinguished with the lower sequence (Unit A2) by a decrease in sedimentation rate starting at ~ 8 ka and deepening of water at ~ 5 ka representing the sea-level highstand. The decrease in sedimentation rate is likely due to the further landward shift of marine and fluvial delta system near the sea-level highstand. During the sea-level highstand, the tidal currents have strengthened, and the Okinose sand bank (Unit A1) was likely initiated during this period (Masuda et al. 2000; Nanayama et al. 2001). Note the increase in sedimentation rate of Unit A1 compared to Unit A1’ at Lines 1–5. (b) Comparison of stratigraphic records with Northern Hemisphere summer solar insolation (W/m2) (red line; Berger and Loutre 1991), orbital precession cycle (amplitude/ no unit) (orange line; Berger and Loutre 1991) and Greenland ice core records (δ18O /‰) (gray line; Wolff et al. 2010). MIS: marine isotope stage. YD: Younger Dryas. H1-H6: Heinrich events