Magnetic properties and sortable silt content from sediment core MD12-3432

This is in particular valid for the magnetic fraction that is one of the key parameters for paleoenvironmental studies in the South China Sea, although poorly used so far. We report here on the analysis of the magnetic properties of a 50 m-long sedimentary sequence retrieved from the northern South China Sea, on the continental slope off the Pearl River mouth.

Magnetic minerals with different coercivities (magnetite, pyrrhotite, and hematite) are mixed. The variations in relative content of these magnetic minerals illustrate influences of various external forcing mechanisms at different timescales. The pyrrhotite content exhibits a long-term increase, which is also observed in illite+chlorite content, indicating a continuous enhancement of supply from Taiwan most likely related to active Taiwan orogeny.