Fig. 1

Bathymetric map and the locations of the sites referred to in this study. The study sites DLW3101, MD12-3429, ZHS-176 and MD12-3432 are marked with red pentagrams. The locations of other sites discussed in the text are also indicated, including GeoB16602-4 and GeoB16601-6 (Liu et al. 2017), and Ocean Drilling Program (ODP) sites 1144, 1145, 1146 and 1148 (Boulay et al. 2005; Wei et al. 2006; Shao et al. 2007; Wan et al. 2010a). The annual sediment discharges of potential sources are indicated by orange arrows (Milliman and Farnsworth 2011). Red shaded area depicts the dispersal of Pearl River-sourced sediments in the Holocene (Ge et al. 2014). Gray ribbon shows the location of the Intertropical Convergence Zone (ITCZ) (Clift 2006). 1: Guangdong Coastal Current (GCC, blue arrow and blue dashed arrow, from Liu et al. 2010); 2: South China Sea Warm Current (SCSWC, pink arrow, from Wang et al. 2010, and Liu et al. 2011); 3: South China Sea Branch of Kuroshio Current (SCSBKC, crimson arrow, from Qiu et al. 2011, Luan et al. 2012, and Nan et al. 2015); 4: Intermediate Water Current (IWC, cyan arrow, from Wang et al. 2013); 5: Deep Water Current (DWC, almond arrow, from Shao et al. 2007). PRMB: Pearl River Mouth Basin; Mt: million metric tons