Palaeoproductivity linked to monsoon variability in the northern slope of the South China Sea from the last 290 kyr: evidence of benthic foraminifera from Core SH7B

• DOI: 10.1144/sp429.10
• Publication Date: 2015-11-07T03:28:24Z
• Authors: Yang Zhou; Fang Chen; Cong Wu; Shaohua Yu; Chang Zhuang
• Keywords: East Asian Monsoon

Abstract A benthic foraminiferal proxy record of 290 kyr, acquired from Core SH7B in the northern continental slope South China Sea, was studied to identify bottom-water environment changes since marine isotope stage (MIS) 8. The changes, including oxygenation and types organic matter flux seafloor, reflect palaeoproductivity fluctuations linked monsoon variability. Four assemblages, characterizing different palaeoenvironmental have been recognized by factor cluster analysis with 32 species 93 samples (>150 µm size fraction). Assemblage Pyrgo spp.– Hoeglundina elegans mainly dominates during interglacial periods MIS 7, 5 3, suggesting well-oxygenated bottom environments low sea surface productivity a weak East Asian Winter Monsoon (EAWM). Uvigerina Globocassidulina subglobulosa is composed constantly high percentage shallow infaunal species, occurring intervals 4, 5, 7 8, which indicates that an enhanced EAWM led seasonality palaeoproductivity, constant fresh labile marine-derived particles seafloor oxygen environment. Melonis barleeanus – Clavulina spp. characterized depend on seasonal supplies more altered refractory distributed (late 3 1), associated intensification EAWM. With diversity abundance, assemblage Globobulimina affinis Chilostomella mediterranensis identified intermediate 8 early 2. Both substantial input terrigenous nutrients increased river run-off primary correlated abundant nutrient severe depletion. As suggested composition SH7B, Sea over last kyr were driven fluctuating variability