Abstract.Geodynamic investigations concerning the registration of the displacements of the geological structures are arranged in the Sudety Mts. and the Fore-Sudetic Block by research workers. These investigations are conducted in the appropriate measurement and control system. One of the segments of this system applies to the observations of the relative displacements of the adjoining geological structures. For this purpose, there is used a special gauge mounted permanently in situ. In objective researches there is used the crack gauge TM-71. This device is used for his periodical readings the phenomenon of light interference(Moiré effect). The objective researches have been conducted since the 70s of the 20th century. As far as processing of the results is concerned, it was based on manual calculations of the registered changes in the three dimensional local space x, y, z. In this paper, there is presented the algorithm of calculations together with the own computer application for processing the results of periodical observations made with the aid of the crack gauge TM 71.

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