Crevice-type caves Pseudokarst Mass movements Electrical resistivity tomography Czech Flysch Carpathians

Crevice-type caves are among the least investigated natural phenomena connected with the development of slope failures. We investigated eight caves in the Czech part of the Outer Western Carpathians to determine their genesis, types andevolution. We performed several analyses, including speleological mapping, evaluation of high- resolution topography above the caves, geophysical (ERT) measurements and structural investigations within cave passages. In accordance with these analyses, various mechanisms responsible for cave development were revealed. Toppling as well as back and horizontal rotation of rock blocks determine the specific morphology and shapes of passages. A relatively novel aspect of the current study is the identification of the subsidence of massive rock wedges due to the widening of cracks.