Sinkhole Formation over a Solution Mining Cavern Field in Maceió, Brazil: Analysis of the Geomechanical Processes — Part II

Abstract At the end of 2023, a sinkhole occurred above the centre of the solution mining cavern field in Maceió, which the seismic monitoring system had forewarned of weeks earlier. The development of sinkholes is predestined by a low level of confinement (horizontal stress) in the overburden, as is the case in the Maceió deposit in a graben structure, and by the role of fluids in controlling the failure mechanism in the formation of chimney-like fracture tubes. Based on analytical and discontinuous HM-coupled 3D models with shear strain softening at joints and bedding planes, the mechanism of sinkhole formation can be explained.