Along‐strike variability in shelf‐margin morphology and accretion pattern: An example from the northern margin of the South China Sea

作者：Haiteng Zhuo, Yingmin Wang, Zhen Sun, Ying Wang, Qiang Xu, Pengfei Hou, Xingxing Wang, Zhongxian Zhao, Wei Zhou, Shang Xu · 发表于：Basin Research · 年份：2018 · DOI：10.1111/bre.12329 · 被引用次数：31 · 研究领域：Geological and Geophysical Studies、Geological formations and processes、Hydrocarbon exploration and reservoir analysis

Abstract Interplays among diachronous tectonism, uneven sediment supply, and local marine hydraulic processes make the northern margin of the South China Sea (SCS) an ideal location to investigate the complexity of along‐strike variability in shelf margins. This study examines shelf‐margin morphology, stratigraphy, and sedimentation from the northern SCS using multichannel seismic reflection profiles complemented with the data from commercial and ocean drilling sites. Analysis of seismic reflection profiles reveals three categories of shelf‐margin cross‐sectional profiles, the concave‐up, linear, and sigmoidal, according to which five margin sectors were recognized. Results show that these margin segments differ in relief, shelf‐edge trajectory, submarine canyon development, and long‐term accretion pattern. The westernmost margin sector, or the Yinggehai (YGH)‐western Qiongdongnan (QDN) margin, has appeared to be supply dominated since its commencement at ca. 10.5 Ma, which is characterized by well‐developed prograding clinoforms, low‐angle shelf‐edge trajectories, and an absence of canyons. Presence of concave‐up profiles is also suggestive of high sediment influx. In contrast, the eastern QDN margin was primarily regulated by local subsidence and faulting, leading to a stationary shelf‐edge migrating pattern and linear upper‐slope morphology. Densely distributed slope‐confined gullies indicate the margin’s disequilibrium and erosive nature. Further east, the Pearl River Mou...