Variations in sedimentation characteristics of the Yellow River Delta under the remote influence of Typhoon Doksuri

To explore the influence of a non-directly passing typhoon on the sedimentary dynamic environment and characteristics of the Yellow River Delta, the impact of the peripheral wind field of Typhoon Doksuri in 2023 on the sedimentary environment of the deltaic area was studied through a combination of in-situ observations, unmanned aerial vehicle (UAV) remote sensing, field survey sampling, and laboratory analysis. Results indicate that: (1) The peripheral wind field of the typhoon caused a rapid change in wind pattern in the delta region, enhanced the estuarine dynamics, and triggered the resuspension of sediments. (2) Variations in marine dynamics resulted in different cross-sectional characteristics within the estuarine delta, which reduced the elevation in the nearshore segment and increased the tidal creeks landside. Due to coastal engineering, sedimentation was increased notably near Kendong 12 Block of the Shengli Oilfield in the study area after the typhoon. The abandoned Qingshuigou River channel experienced erosion seaward and sedimentation shoreward. (3) In addition to the elevation change, significant changes in sediment grain size occurred in different cross-sections of the delta. The changes in grain size were influenced by various factors such as tidal creek erosion, river sediment transport, estuarine erosion, and filling of abandoned river channels, showing spatial differences. The findings of the study demonstrate that typhoons do not directly pass through the delta can still affect the sedimentary evolution process in this region through their peripheral wind field, which should be taken into consideration seriously in future research on delta sedimentary evolution and disaster prevention and mitigation efforts.