Figure 1

Magnetic, chemical and micropalentological data from core TB2, compared with paleoceanic data from other regions. The data from TB2 are (a) magnetic susceptibility (χ), (b) anhysteretic remanent magnetization (ARM), (c) ARM/ χ, a magnetic grain size proxy, (d) S/Ti ratio, a pyrite content proxy, (e) Ca/Ti ratio, (f) the number of foraminifera fossils per gram, and (g) planktic δ¹⁸O. The data from other regions are (h) diatom-based salinity from Osaka Bay¹³, and (i) planktic δ¹⁸O from U1313 in the mid-latitude North Atlantic¹². The vertical axis for (a)–(g) is the u-channel core depth in m. The data of (a)–(e) are of 1-cm intervals. For (d) and (e), 7 point moving average data are plotted. The oxic events (or reduction in anoxia – see text for details), observed as broad or sharp minima in all of ARM/χ, S/Ti and Ca/Ti ratios, are numbered. The major oxic events that coincide with low sea-level events are tied by thick solid lines numbered 5, 7, and 10. Brief oxic events, less than 40 cm in thickness, are tied by thin solid lines numbered 1, 2, 6, 8, and 9. Weaker oxic events observed as broad minima are tied by thin broken lines numbered 3 and 4. The solid triangles in (h) and (i) show orbital scale sea-level lowstands. The open arrowheads in (i) show sporadic occurrences of iceberg discharge during the MIS 19 interglacial¹². MBB: Matuyama-Brunhes boundary, Byk-E: Byakubi E tephra.