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Manila Trench is a critical region for revealing the tectonic evolution and source-to-sink process of the South China Sea, but the sediment provenance in the northern part of the trench remains unclear. In this study, we present a first detrital zircon U-Pb geochronology of sediments in the northern Manila Trench, in the vicinity of Northwestern Luzon Island, to identify the sediment provenance and understand the source-to-sink process in marginal sea The study shows that the sediments yielded multiple zircon age populations at ca. 123, 221, 443, 565, 906, and 1871 Ma. A detailed detrital zircon age study indicates that the sediments were derived mainly from Taiwan Island, China, rather than the nearby Luzon Island In comparison with the modern drainage systems surrounding northeastern South China Sea, this study further confirms that the sediments were primarily originated from the Gaoping River (ca. 45%), with subordinate contributions from the Lanyang River (ca. 24%) and Min River (ca. 19%). The study also elucidates two completely different sedimentary transport modes in the northern Manila Trench. The transportation of sediments from southwestern Taiwan Island is primarily related to the gravity-driven transport through the Gaoping submarine canyon. Furthermore, a quarter of detritus derived from eastern Taiwan Island might have been transported by the deep-water circulation of the Luzon Strait. This study highlights the provenance and transport pathway of sediments in the northern Manila Trench and provides a solution for understanding the source-to-sink process in the marginal sea. [ABSTRACT FROM AUTHOR]

The Holocene sedimentary evolution in the northern South China Sea has significant implications for sedimentary records resulting from combinations of climate change, sea level rise, and changes in surface circulation. U-Pb geochronology and Lu-Hf isotopes of detrital zircons from the Holocene sediments at the head of the Shenhu submarine canyons, integrated with onshore geochronological data reveal variations in provenance related to these factors. The detrital zircons exhibit a wide range of U-Pb ages from 3829.7 to 41.5 Ma characterized by peak ages centered on 140–154 Ma, 240–258 Ma, 425–452 Ma and 738–991 Ma. Zircon Hf isotopic compositions show a broad range of 176Hf/177Hf ratios from 0.2800714 to 0.282924, with ε Hf (t) values ranging from −27.8 to +14.3. Our results suggest that the Holocene sediments were primarily derived from the Pearl River system and the drainage systems in Taiwan, and the sources in Hainan and Luzon are not represented in these sediments. A rapid shift from Pearl River-dominated to Taiwan-dominated provenance occurred between 4.91 and 4.45 ka BP, which is interpreted to be caused by sea level rise and variations in the surface circulation in the northern South China Sea during the Holocene. Our study also reveals that the reworking of ancient continental crust dominated the evolution of the South China Craton, including tectonic-magmatic events at ca. 2491 Ma, 1843 Ma, 968 Ma, 810 Ma, 440 Ma, 251 Ma and 147 Ma. In contrast, Neoproterozoic accretion of the Cathaysia and Yangtze blocks was accompanied by juvenile additions to crustal growth. • Detrital zircon revealed a variable provenance in the Shenhu submarine canyons • Quantitative analysis indicated Pearl River and Taiwan were the major sources • Shift in provenance was related to the sea level rise and surface circulation • Reworking of ancient crust dominated the South China Craton since Archean [ABSTRACT FROM AUTHOR]

The northern shelf of South China Sea is an important passageway for the transportation of sediments from the terrigenous source to the oceanic sink, but the provenance and dispersal patterns of sediments remain largely unclear. Here we report the results of zircon grain-size analysis and U-Pb geochronology to investigate the sediment provenance and illustrate the transport and dispersal patterns of sediments on the continental shelf of the northern South China Sea. The results show that detrital zircon U-Pb ages within sediments are characterized by a major peak at ca. 150 Ma, as well as three minor age populations at ca. 240 Ma, 400–500 Ma, and 900–1000 Ma. A detailed provenance study suggests that these sediments were primarily derived from both the Pearl River catchment and the drainage systems in Taiwan Island. Our study confirms that the transportation and dispersion of sediments were largely controlled by both topography and hydrodynamics of sea. The sediments in the inner continental shelf were transported from the Pearl River drainage system and subject to the Guangdong Coastal Current, whereas the sediments in the middle and outer continental shelf were markedly influenced by the South China Sea warm current. This study elucidates the transport and dispersal patterns of detrital sediments in the marginal sea by comprehensive analyses of detrital zircon grains. • Zircon grain-size and U-Pb dating were utilized to decipher the provenance and dispersal patterns. • The sediments were primarily derived from the sources of Pearl River and Taiwan Island. • Redistribution of sediments was influenced by the shelf current as the rising of sea level. • Different mineral grain sizes settling differentially can affect sediment provenance. [ABSTRACT FROM AUTHOR]