Seismic Multiple Attenuation in the Continent–Ocean Transition Zone of the Northern South China Sea

In this study, we process four new multichannel reflection seismic profiles acquired in 2015 and 2016 the continent–ocean transition zone (COT) of northern South China Sea (SCS). We apply a multi-domain, progressive, seabed-controlled denoising technique obtain good effect. Combining velocity analysis multi-round time domain forward modeling, analyze types characteristics multiples study area formulate an effective demultiple to attenuate strong seabed multiples, diffracted from rough seafloor, other deep reflectors. The processing results show that sea surface-related multiple elimination predicts accurately by data convolution, has effect attenuating multiples. Diffracted attenuation method extracts high-frequency high-energy suppresses energy ratios primary events. To select predictive deconvolution periodic after many trials detailed analysis. combination these different techniques sequence proves be quite COT. imaged crustal structures near COT often magmatism and/or basement uplifting. faulted thinned continental crust adjacent corresponds lowest free-air gravity anomalies. Gravity anomalies increase oceanic crust. An exception is northeast SCS, where relatively wide shows very high anomalies, likely induced mantle upwelling serpentinization.