Subsidence is always a long-term effect from the exploration of natural gas storage cavities. The internal pressure being less than in situ pressure leads to cavity convergence with has economical consequences as well as possible outcomes on the surface. After reviewing the subsidence phenomenology, by identifying what can be observed at the surface, and its environmental and structural consequences, some empirical and analytical means of estimating its deformation values are referred. With more detail, a numerical application is presented which uses coupled boundary and finite elements for subsidence evaluation due to deep storage cavities. This lasts characteristic gives rise to large extensions of deformed zones towards the surface. A real case of a storage cavity field with subsidence measurements made for more than ten years is taken as example and some predictions are made on future subsidence and horizontal displacement.