The Cave under the Spisska hill: Preliminary monitoring results of the block movements

摘要

The Cave under the Spisska hill (Levocske vrchy Mts.) is the longest pseudokarst cave in Slovakia. Together with other caves it was formed by the movement of sandstone blocks and slabs along the bedding planes and fissures on the south and southeast slopes of the Spisska hill during the Quaternary. The movement can be defined as lateral spreading and very slow rock block sliding, less as toppling. Block movements inside the cave are monitored by the crack gauge of the TM-71 type since April 2007. The device is based on the moire effect and is capable to detect 3D micro-displacements along three Carthesian coordinates - X, Y and Z with the accuracy up to 0.01 mm and rotations up to 0.01 [it/200]. The paper summarizes the preliminary monitoring results and provides their interpretation.