Multiple steps of earth fissuring caused by ground-water withdrawal

Earth fissures associated with ground-water withdrawal are surface expressions of fractures at depth that are caused by aquifer movement. After cutting the land surface, fissures can either remain active for some time or become inactive depending on whether triggering forces are large enough for further development. Examining the genesis of land surface fissures provides insights needed for predicting and controlling fissures. In this paper, conceptual models of fissure generation are derived by applying the physics of fracture mechanics to the theory of poroelastic aquifer deformation. A stepwise classification of earth fissure genesis is suggested. The classification considers geology of heterogeneities, relative movement of aquifer materials, and a corresponding driving or triggering force for each step. The conceptual models discussed in this paper provide insight into the fissuring process.