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The northeast Taiwan margin provides an excellent example of the route of sediment flux from a small mountainous river, the Lanyang River, to a deep-sea basin, the Southern Okinawa Trough (SOT), via a very narrow（8–14 km in width）Ilan Shelf at different time scales. Based on seismic and sub-bottom chirp profiles and onshore borehole and offshore core data, we identify three echo types on the Ilan Shelf that delineate sheets of sediment, mass movement deposits, and echoes indicative of igneous activity. By recognizing lithofacies and seismic facies changes, the Last Glacial Maximum Unconformity and maximum flooding surface are correlated in onshore cores and offshore reflection seismic profiles. With the aids of sequence stratigraphic analysis, the postglacial sedimentation rates on the Ilan Shelf are estimated to range from 0.04 to 1.53 cm/yr. Considering its sediment budget in a source-to-sink system, the Ilan Shelf can be regarded primarily as a temporary trap for fluvial sediment discharged from the Lanyang River. Overall, it has trapped at least 50% of the discharged sediment during the Holocene, and the bulk of sediment was transported, primarily via mass movement to SOT. We deduce that earthquake-induced faulting, axial incision in the channel, and retrogressive failures appear to be triggers for mass wasting, which then combined with channel transport, can play leading roles in rapid downslope transportation to the trough. This inference is indicated by high deposition rates in the western end of SOT and widely distributed mass transport deposits observed in the shallow strata of SOT. We found that the deep strata of SOT are deformed by normal faults, indicating that the sediment accommodation space is structurally controlled by the active back-arc extension. This study documents that frequent typhoons and flooding events, together with strong tidal currents, are significant agents of sediment input over the short term. In contrast, earthquakes and volcanic events occasionally affect sediment dispersal from the Ilan Shelf to SOT. • We firstly present sediment dispersal patterns of the Ilan Shelf since the Last Glacial Maximum. • Combining seismic and well data onshore and offshore, we exhibit Ilan Shelf as a buffer zone temporarily storing sediments within the S2S system. • Mass wasting processes combined with channel transport play leading roles in rapid downslope sediment transportation from the Shelf to SOT. • Ilan Shelf plays as a temporary trap for at least 50% of fluvial sediment discharged from the Lanyang River during the Holocene. [ABSTRACT FROM AUTHOR]

Whether the formation of the isolated sand body deposition in the forebulge area of a foreland basin system is structure- or deposition-controlled has puzzled geologists for decades, although sand body deposition is generally believed to be indicative of the position of the flexural forebulge in a foreland basin. The formation of a modern sand body in the forebulge area is thus examined by multi-scale geophysical observations based on combined reflection seismic profiles and compressed high-intensity radar pulse (CHIRP) profiles across the sand deposition along the forebulge of the Western Taiwan Foreland Basin (WTFB), which is a Late Miocene-present foreland basin in the overfilled stage. These profiles suggest that the accumulation of the sand deposits along the forebulge of the WTFB is not directly associated with forebulge faultings. The relief map of the forebulge deposit substratum shows a northwestward tilting slope, and the isopach of the forebulge sand body indicates that a large part of the sand body accumulated along the axis of the Taiwan Strait and the subdued forebulge of the WTFB. The difference between the prevailing directions of tidal currents between the Taiwan Strait and the East China Sea reflects the probable sedimentary influence of the cratonward migrating fold-thrust belt within a foreland shelf. We suggest that the formation and distribution of the sand deposits along the forebulge of the WTFB are generally controlled not only by the transverse downslope sedimentation but also longitudinal hydrodynamic processes at distal parts of the foreland basin. Our explanation provides a plausible tectono-sedimentary cause of the sand body deposition in the forebulge area in an overfilled foreland basin. The sedimentary dynamics of the sand body in the Taiwan Strait may be applicable for understanding the formation of isolated sand bodies in the distal part of the Cretaceous Western Interior Foreland Basin. [ABSTRACT FROM AUTHOR]

We re-examined the cessation of the South China Sea seafloor spreading by using radioactive dating and fossil assemblage of the ETO, and the Te-derived age. The youngest available age for the fragment of the South China Sea is ∼15 Ma and is more consistent with those suggested by previous studies. Moreover, recent IODP Expedition preliminary results suggested that the hemipelagic claystone layer stratigraphically bounded by igneous sequences of massive lava flow rock is Early Miocene in age. Therefore, the previous interpretations are more inclusive than those provided by Barckhasen et al. (2014) and indicate that a slow spreading ridge was more plausible to have occurred during the seafloor spreading of the South China Sea. [ABSTRACT FROM AUTHOR]