Remotely obtained geodetic survey data can be used to detect anomalies in the terrain surface over different geological structures, like faults or deposit boundaries. Some computer techniques are helpful to extract the influence of geological phenomena on typical distribution of the measured elevations. Certain disturbances in profile lines can be considered as additional, human-induced effects or caused by geological processes. The paper demonstrates such an analysis basing on geodetic data with some support of geophysical results. The examined morphological profiles and profiles of subsidence bowls caused by mining in the area of Inowroclaw (central Poland) illustrate the problem of an underestimated mechanism in non-geological disciplines. For geologists this is another example of environmental interaction between relief-forming processes and subsurface conditions. Furthermore, it brings additional information about processes of mining subsidence, which is the primary topic of this study. Mutual relationships between vertical displacements induced by mining or other factors and morphological profiles point to the dominant role played by mobility of geological structures, as shown by correlation between geodetic and geophysical data.
The paper summarizes up-to-date knowledge of the contemporary tectonic stress field in Poland and compares the results of geophysical measurements with mathematical models. The extensive set of data provided by borehole breakout analyses is supplemented by hydraulic fracturing tests, earthquake focal mechanism solutions and preliminary resolution of regional intraplate motions from GPS measurements. Frequent breakout presence shows that tectonically driven anisotropy of horizontal stress is a common feature in the study area. Roughly N-S direction of maximum horizontal stress (SHmaxx) in Eastern Poland differs significantly from Western European stress domain. This difference is produced by tectonic push of Alcapa, which is successively compensated within the Teisseyre-Tornquist Zone (TTZ) and in the Upper Silesian segment of the Outer Carpathians. In the western part of Poland stress directions are ambiguous due to interplay of several additional tectonic factors. Most of hydraulic fracturing data and earthquake focal mechanism solutions indicate strike-slip stress regime in Eastern Poland where stresses are in equilibrium with preferentially oriented faults of Iow friction (0.16). Limited data from Western Poland suggest normal fault stress regime. Good conformity between directions of 5Hm", and intraplate motions occurs from comparison of breakout and GPS data. Finite element modelling shows that the most important factor shaping the stress field in Eastern and Central Poland is the Adria push transmitted through the Pannonian region. Secondary, but still notable factors are differentiation of loads along the Mediterranean collision zone and changes in magnitude of the ridge push force along the NW Continental passive margin of Europe. Results of rheological modelling indicate that the crust is entirely decoupled from the mantle in the Fore-Sudetic Platform, partial uncoupling in the base or the upper crust is possible in the TTZ while in the East European Craton (EEC) the whole lithosphere is coupled. The comparison of different set of data and models presented here provides a comprehensive geodynamic scenario for Poland, however, a number of unresolved questions still remains to be addressed.
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Wśród procesów wyróżniono: nieobserwowalne i obserwowalne, a wśród obserwowalnych: trudno-, średnio- i łatwo obserwowalne. Przechodzące w siebie procesy: zmęczenia skał, ich pękania i przemieszczania połączono w jedną triadę. Przedstawiono wyniki badań zmęczenia, pękania i przemieszczania skał w drugiej połowie XX w. w Polsce. Określono obserwowalność poszczególnych procesów badanej triady. Wskazano na wagę przedstawionych rozważań dla właściwego rozwiązania problemów geodynamiki współczesnej, paleodynamiki oraz tektoniki i paleotektoniki.
EN
There are distinguished among processes: inobserved and observed: hardly-, moderatly-, easily to distinguish. The transitive themselves processes: rock fatigue, rock fractures and rock displacements are jointed in one triad. There are presented results of studies in the rock fatigue, fracture and displacements in the second half of the XX Century in Poland. The observation of the particular processes in the studied triad is defined. Some consequences from the presented considerations for the proper solutions of the recently geodynamical, paleodynamical, tectonical andpaleotectonicalproblems were noticed.
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