Abstract The deep‐sea represents the largest sediment accumulation area on earth, yet it remains largely unexplored by humans and many sedimentary dynamic processes remain poorly understood. Internal waves are important deep‐sea dynamic processes and widely present in the global ocean, but very few internal wave deposits have been discovered. This study focuses on the Dongsha slope of the South China Sea, where sediment core, observations by bottom lander, sub‐bottom and seismic profile were conducted. We combine modern analytical techniques such as scanning electron microscopy, particle size analysis, grayscale images, and radiocarbon content on multiple depth layers of a 310 cm sediment core to comprehensively identify the internal wave deposits. Using criteria such as occurrence, composition, particle size, grain‐sequence bedding, sorting, sedimentary structures, bioturbation structures, and sea level changes, we conclude that the sediment core comprises internal wave deposits. This study represents the world's longest and continuous internal wave deposits in the modern ocean to date. The annual transport volume of internal waves along the Dongsha slope is estimated to be approximately one‐fifth of the sediment transported from rivers into the sea near the Dongsha region. Internal waves emerge as the primary driving force for sediment transport, dictating the sedimentation processes across the entire Dongsha slope. Our research provides valuable references and support for the identification and analysis of internal wave deposits around the world in the modern ocean.
Tian et al. (Fri,) studied this question.