Subsidence

Subsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. It involves little or no horizontal movement, which distinguishes it from slope movement. Processes that lead to it include dissolution of underlying carbonate rock by groundwater, gradual compaction of sediments, withdrawal of fluid lava from beneath a solidified crust of rock, mining, pumping of groundwater or petroleum, and warping of the crust by tectonic forces. Subsidence resulting from tectonic deformation of the crust is called tectonic subsidence and can create accommodation for sediments to accumulate and eventually lithify into sedimentary rock. In karst terrains it can cause sinkholes that are many hundreds of meters deep.