Study Of Gas Hydrate And Submarine Landslide

The reserves of gas hydrates is enormous, it is considered one of alternative energy in the future. In the submarine slopes, the significant volume change occurring during hydrate dissociation combined with the low permeability sediments or hydrate seals result in rapid build up of excess pressures, which may induce instability. This destructed deep-sea oil and gas drilling, pipelines, submarine cables and other submarine construction facilities, endangering human life and property. Therefore, the study about hydrate and submarine landslide is great significance for evading risk effectively and developing hydrate securely.This paper analyzes the characteristics of gas hydrate formation and gas hydrate decomposition , established pore pressure model of hydrate decomposition; based on Limit equilibrium theory, use pore pressure model modified infinite slope equation; then Using the infinite slope equation and the modified finite element method analyze different situations and Storegga landslide, Beaufort Sea, comparison results show that the infinite slope equation is more safe, it does provide comparable results at shallower depths to failure surface and it does not need to input the parameters repeatedly can save time. Applied the amend infinite slope equation for a parametric analysis of the impact of gas hydrate dissociation on the stability of seabed soils. The analyses identified that the magnitude of the overburden, the void ratio, the plasticity index, the quantity of gas hydrate present are the parameters that significantly impact stability of a slope during gas hydrate dissociation using this model. At last, the paper established the relationship of mining hydrate saturation, the angle of hydrate mining area and cover thickness with Mining pressure , implementing a quantitative analysis about the possibility of occuring submarine landslide when mining hydrate, the results suggests that use straight wells explore undersea hydrate are not prone to induce landslide.