A preliminary study on the acoustic properties of seafloor sediment in the southern U-boundary of the South China Sea

The acoustic properties of seafloor sediment are essential parameters in the exploration of marine resources, ocean scientific research and ocean engineering. Seafloor sediment samples were collected at the southern U-boundary of the South China Sea (SCS), and the acoustic and physical properties were measured in the laboratory. The correlation between physical and sound speed ratio (SSR) was discussed, and SSR-physical property empirical regressions in the Sunda Shelf were established for the first time. Compared with the northern continental shelf of SCS, the Sunda Shelf are mainly silty and sand sediment, and the SSR ranges from 0.994 9 to 1.094 4, which has higher SSR than the northern continental shelf, implies that the Sunda Shelf is a high SSR area. Since the same kind of sediment has different physical properties, the single physical parameter of sediment cannot fully represent the acoustic properties of sediment, therefore, the multiple parameter prediction model should develop in the future to improve the prediction precision.