Characterization of channels related to carbonate platforms and their geological control in the Xisha Sea area of the South China Sea

The study of carbonate platforms has long been a focal point for geologists due to their significance as preferred hydrocarbon reservoirs and their sensitivity to environmental changes， leading to the accumulation of extensive knowledge. However， limited research has been devoted to the channel systems associated with carbonate platforms. Based on high-resolution multibeam mapping and seismic profile interpretation has enabled the first systematic classification of carbonate platform channels into four distinct types: the peri-reef channel， the peri-platform tidal channel， the steep slope canyon， and the deepwater channel. Concurrently， high-resolution seismic data have provided the opportunity to precisely characterize their seismic reflection features. Paleomorphology， clastic supply of carbonate sediments， and relative sea level changes are identified as key controlling factors in the evolution of these channel systems. The spatial distribution and geological configuration of different channel types are primarily governed by the paleomorphology of the carbonate platform. The intensity of erosion and sedimentary processes is mainly influenced by the availability and flux of carbonate clastic material. Furthermore， relative sea level changes initially affect the development of the carbonate platform itself， thereby indirectly influencing the evolution of its associated channel system paleomorphology.