Suspended Sediment Transport and Deposition due to Strong Regional Shear Current Front: an example from the shelf waters off eastern Shandong Peninsula

Key words: 
• suspended sediment /
• Yellow Sea cold water mass /
• yellow Sea warm current /
• muddy wedge /

Abstract: Based on field data of temperature, turbidity and  suspended matter concentration  in summer and winter derived from the project named National Coastal Sea Comprehensive Investigation and Evaluation (908ST02), the suspended sediment transport and deposition due to strong regional shear current front off eastern Shandong Peninsula were studied, combined with observation from B1 and B2 sections, circulation simulation in winter by POM model and shallow seismic profile. The results show that the transportation mechanism of suspended matter off eastern Shandong Peninsula is similar to the existing rule in East China Sea: deposition in summer and transport in winter. In summer, not only suspended matter was restricted near bottom by thermocline, but also restricted by the front formed by coastal currents off eastern Shandong Peninsula and northern Yellow Sea cold water mass. Therefore suspended matter mainly deposited in summer. In winter, with the help of strong northeastly wind and the thermocline, the turbidity was high vertical mixing was better off eastern Shandong Peninsula. However, two strong shear current fronts could be found on both sides of the topset of mud wedge, which was respectively generated by northward upwind compensation current along eastern Shandong Peninsula in the middle and lower water, northward Yellow Sea warm currents and southward coastal wind currents above topset of mud wedge. The two strong shear current fronts prevented suspended sediments from bottomset of the mud wedge getting cross eastern Shandong Peninsula continental shelf peripheral, which was helpful to omegashaped (‘Ω’) mud wedge formation off eastern Shandong Peninsula.