The gravity effect of an upward migrating brine cavity in the Twenthe-Rijn concession area, East Netherlands

摘要

Surface subsidence in the Twenthe-Rijn concession area near Hengelo, East Netherlands, is caused by elastoplastic deformation of salt and overburden, and upward migration of overmined salt solution cavities by subsequent failure of individual roof layers. Whereas in most areas this subsidence is in the order of several millimetres per year, there have been cases where a sudden rapid increase in subsidence resulted in the formation of a bowl or even a sinkhole of several meters (Figure 1). Numerous studies have been carried out concerning cavern behaviour and related surface subsidence. It has been proven difficult to develop a method that can predict future behaviour of migrating brine cavities.