Subsidence map of underground mining influence for urban planning; an example from the Czech Republic

The objective of this study is to produce a subsidence map linked to underground mining influence in a mining region. Ground subsidence represents the most important characteristic of a subsidence basin. However, ground subsidence itself does not carry information on geohazards by means of the impacts on the built-up area. Based on long-term experience and studies carried out, three basic subsidence intervals of varying influence were proposed. The lowest degree of undermining influence is connected with subsidence up to 12 cm; the second category is for subsidence from 12 to 100 cm, where constructions are considered possible under certain conditions but special technological procedures must be adhered to; and the third category of hazard is for subsidence over 100 cm. The study was implemented in the largest mining region (black coal deep mining) of the Czech Republic, in the locality of Orlova, Petrvald and Karvina. The study also involved an overall evaluation of subsidence influence, its variation with time, its relation to the current built-up area and to the future built-up area according to the land use plan, and its relation to engineering-geological zones and landslides.