Advances on the safety related with natural gashydrate exploitation

Abstract

Gas hydrate dissociation can cause the instability of marine stratums. The geological hazards and environmental effects relative to gas hydrate exploitation have attracted great concerns. In this paper, the studies on the hazards (Marine landslide, debris flow, damage of structures etc.) and environmental effects are summarized. The main factors of hydrate dissociation are discussed. Six typical large marine slides are introduced at beginning and, then the studies on the mechanism and failure critition are reviewed. The layered fracture and gas outburst and the instability of marine structures due to gas hydrate dissociation are illustrated and the critical conditions are discussed. The monitoring technologies and the data processing methods during gas hydrate dissociation are introduced. The studies on the mechanical and physical propertis of gas-hydrate-bearing sediment closly related hazards are summarized also. Finally, the problems and future study topics on the safety relative to gas hydrate exploitation are presented.