Conical ground subsidence morphodynamics in the Yellow River Delta, China: Insights from InSAR analysis

Anthropogenic-induced subsidence in populated deltas poses critical environmental challenges. However, quantitative links between hydrological processes and land deformation remain poorly understood. Focusing on the Yellow River Delta as a typical study area, this research employed time-series InSAR techniques to monitor land subsidence and systematically analyze its spatiotemporal characteristics. This study quantitatively assessed the dynamic impacts of groundwater dynamics, underground brine resource exploitation, oil-gas extraction, and land use types on subsidence. InSAR-based analysis revealed a pronounced subsidence belt along the Laizhou Bay-Bohai Bay arc-shaped coastal zone, characterized by funnel-shaped subsidence patterns with differentiated evolutionary trends. The spatial distribution of subsidence reflected underlying geological structures and variations in anthropogenic pressure. This study establishes that anthropogenic activities dominate contemporary subsidence patterns in the Yellow River Delta. Quantitative analysis demonstrates that groundwater extraction, brine mining, and hydrocarbon exploitation constitute primary deformation drivers. These findings redefine coastal risk management priorities, confirming human activities as the critical control on land subsidence – with direct implications for infrastructure resilience, wetland stability, and deltaic sustainability. Building on this mechanistic foundation, future research should integrate InSAR-GPS-hydrogeological monitoring to resolve spatiotemporal lags in fluid extraction responses and multi-factor coupling effects.