Submarine cables in Jiangsu offshore waters traverse soft clay, silty sand, and dense clay, making them vulnerable to dropped-anchor impact and drag-induced cutting. This study develops a dynamic burial-depth framework for stratified seabeds using layer-local penetration coordinates and integrated resistance work. A submerged-anchor model evaluates vertical impact penetration, while an environmental-load criterion activates a Hall-anchor rule for horizontal dragging. The recommended cable-control depth is the larger of the impact and drag depths, with explicit allowances for scour, construction deviation, and uncertainty. A representative COMSOL model verifies layered deformation, anchor–soil interaction, and local resistance concentration. Four anchor cases show theory–test differences of 0.07–0.35 m (4.6–13.8%). Routine middle-route depths range from 1.72 to 2.50 m across four Jiangsu areas, whereas major-channel scenarios require separate assessment. The framework supports segment-wise burial design and lifecycle reassessment, while site investigation and operational risk analysis remain essential.

Submarine cables,burial depth,anchor hazard,layered seabed,dynamic protection