DO EQUILIBRIUM CONDITIONS EXIST DURING SEDIMENT TRANSPORT STUDIES ON CONTINENTAL MARGINS - AN EXAMPLE FROM THE EAST-CHINA-SEA

Analysis of high-resolution (<1 m) GeoPulse seismic reflection and Chi rp sonar data from the continental margin of the East China Sea reveal s the presence of a thin(1- to 5-m-thick) sediment veneer over a highl y reflective transgressive surface. Due to reverberation of the output signal and the effect of the bubble pulse, this veneer may erroneousl y be interpreted as a laterally continuous feature. Sonar data, which does not suffer from these ghosting effects, reveals that the sea bott om is often an erosional surface that exposes older, relict sediments, which were deposited under a radically different hydrodynamic regime than exists in these locations today.