As potential targets for deep-sea hydrocarbon exploration, continental slope canyon–fan systems preserve records of sea-level fluctuations and paleoclimatic changes. The Quaternary canyon–fan system in the Baiyun sag represents a potential reservoir for sand-rich deposits. However, the mechanism governing its Quaternary spatiotemporal evolution, which is influenced by multiple factors, remains unclear, significantly constraining the prediction accuracy of sand-rich deposits in this area. Based on three-dimensional (3D) seismic, drilling/logging, and paleontological datasets, a Quaternary isochronous stratigraphic framework was established for the northern continental slope of the Baiyun sag. Seismic interpretation techniques were employed to delineate the morphology and architecture of slope canyon group and associated slope fans, which enabled the development of a spatiotemporal evolutionary pattern for canyon–fan systems and the revelation of their multifactorial driving mechanisms. Our study demonstrates that: (1) Within the Quaternary target strata, one second-order (T₀) and five third-order sequence boundaries (SB1–SB5) have been identified, leading to the delineation of five third-order sequence units (Sq1–Sq5) with distinct structural characteristics; (2) Sedimentary geomorphic units such as shelf-margin deltas, submarine gullies, canyons, and slope fans have been recognized, collectively forming a complete deep-water source-to-sink (S2S) system; (3) The evolution of canyon–fan systems commenced during the canyon–fan formation stage (Stage 1) under a transgressive background, progressed through the peak stage of canyon incision and fan progradation (Stages 2–3) under a regressive background, and culminated in the canyon–fan decline stage (Stage 4) under another transgressive background; (4) Macroscopic factors, including tectonic activity and climate–sea level changes, controlled sediment supply and the development of canyon–fan systems, while local factors such as sediment provenance patterns and the distance between canyons and the shelf margin regulated the structural configuration and spatial distribution of these systems. The dominant controlling factors undergo shifts over time. Elucidating the spatiotemporal evolutionary patterns of Quaternary continental slope canyon–fan systems, revealing their multifactorial driving mechanisms, and deepening the understanding of dynamic processes within deep-water S2S systems will provide a theoretical basis for subsequent predictions of sand-rich deposits and offer a practical paradigm for global canyon–fan research.

The study of sequence stratigraphy often focuses on shallow marine and shelf-edge regions, while research on deep-sea stratigraphic sequences remains relatively weak. This study, based on highresolution 3D seismic data and drilling information, utilized sequence stratigraphy and seismic sedimentology as guidelines, and employed seismic interpretation methods to performed a division of deepsea stratigraphic sequences within the Romney 3D seismic survey area in the deep-water Taranaki Basin, New Zealand. Furthermore, it analyzed the characteristics of typical depositional systems and their associated controlling factors. The findings are as follows: (1) Based on seismic reflection termination relationships and seismic facies characteristics, four second-order sequence boundaries and nine thirdorder sequence boundaries were identified, resulting in the delineation of three second-order sequences and twelve third-order sequences in the basin. (2) Five seismic facies were recognized, corresponding to five typical sedimentary bodies: mass transport deposits (MTDs), deep-water channel, levee deposits, deltaic deposits, and pelagic deposits. However, due to the relatively thin sedimentary thickness of carbonate sediments, the seismic facies characteristics of carbonate sediments cannot be discerned in seismic data, but can be identified based on well data. Deltaic sediments mainly developed during the rift stage of the basin, while carbonate sediments formed during the transition from a passive to an active margin. Deep-water channel and levee deposits and MTDs emerged during the active margin stage, while pelagic deposits are ubiquitous in marine environments. (3) The uplift of New Zealand's interior and climate-driven erosion caused the resurgence of clastic sediments, which began to be transported to the deep sea, the seafloor topography would directly affect the movement path of sediment gravity flow, and sediment supply can affect the development and evolution of sedimentary systems. (4) Event deposits boundaries, such as erosional scour surfaces formed by channels and unconformities created by MTDs, can serve as boundaries for the division of deep-water stratigraphic sequences. This study proposes a method for delineating deep-water stratigraphic sequences using event deposits, particularly suitable under conditions where the influence of relative sea-level changes on deep-water deposits is relatively weak. This research not only enhances the understanding of deep-water depositional sequences but also provides a reference for studies on the evolution of deep-water deposition and its controlling factors in research areas with similar geological backgrounds worldwide.