天然气水合物分解是导致海底边坡失稳的重要原因之一，科学评价含水合物储层海底边坡稳定性是安全高效开采的前提。文章基于有限元强度折减法，对中国南海神狐海域某海底边坡稳定性进行分析，重点考虑了天然气水合物分解对抗剪强度的影响，研究结果表明：随着天然气水合物分解程度的提高，边坡稳定性整体呈现降低趋势。分解程度在40%~80%之间时，边坡稳定性对水合物分解变化较为敏感，随着分解程度的提高，安全系数迅速减小，最危险滑动面深度显著增加，超过水合物储层位置。通过有限元数值模拟，本研究建立了一套对含水合物储层边坡稳定性分析的方法，为海洋天然气水合物资源开采中的地质风险评价和防控奠定理论基础。

The decomposition of marine gas hydrates is one of the important causes for the instability of submarine slopes. In order to exploit natural gas hydrate safely and efficiently, it is necessary to evaluate the stability of seabed slopes containing hydrate reservoirs scientifically. Based on the finite element strength reduction method, the stability of a submarine slope in the Shenhu area of the South China Sea is investigated, with a focus on the impact of marine gas hydrate decomposition on shear strength. The results are as follows. As the degree of decomposition of marine gas hydrate increases, the stability of the slope shows a decreasing trend. When the degree of decomposition is between 40% and 80%, the stability of the slope is sensitive to changes in the degree of hydrate decomposition. As the degree of decomposition increases, the safety factor decreases rapidly and the sliding depth of the anti-shear failure increases significantly, exceeding the position of the hydrate reservoir. A method for analyzing the stability of slopes in hydrate-bearing reservoirs has been established with finite element numerical simulation, and lays a theoretical foundation for geological risk assessment and management in the extraction of marine gas hydrate resources.