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Analyses of available data (newspaper reports, historical and church chronicles, chronical earthquake overviews, travel books, monographies, research papers, etc.) on effects of the earthquakes that shook the greater Ormož area at the Slovenian-Croatian border in the 1838 and 1839 revealed that one of them, recorded in a number of regional and global catalogues, is in fact a fake - the earthquake of 26 August 1838 never happened. This error creeped into various reports and studies, and then into many relevant catalogues, so this event should by systematically erased from the catalogues used to estimate seismicity rates in the neighbourhoods of north-western Croatia, north-eastern Slovenia, and south-western Hungary. Regarding the earthquake of 31 July 1838, we used important new sources of information that have not been consulted in any previous study. This made inversion of macroseismic parameters more robust. Our estimates of the macroseismic moment magnitude (Mwm = 4.8) is mostly higher than the values reported in the available catalogues. Reliable information on the effects of the smaller event of 22 March 1839 were found for two localities only, so its epicentre was placed into the town of Ormož where the maximum intensity was observed. Its estimated moment magnitude (Mwm = 4.4) is close to the median of values found in the six consulted catalogues that listed this event. The macroseismic epicentre of the 1838 earthquake lies close to the junction of surface traces of the Donat strike-slip fault and the reverse Čakovec fault. Based on their assumed geometry and the location of the macroseismic hypocentre, we give slight preference to the Donat fault as the seismogenic source. [ABSTRACT FROM AUTHOR]

The paper presents the empirical use of height movement kinematic model of Earth's crust created for territory of the Croatia, Slovenia and Bosnia and Herzegovina, in order to determine the relative height displacements of crust discrete points between different epochs. Also, presents the use of this model for the purpose of direct levelling measurement reductions determination, from surveying epoch to another unambiguously selected epoch, i.e. in purpose of height movement effects elimination from levelling network node benchmarks. For Croatian territory the quality of the kinematic model is indirectly tested, founded on the comparison of levelling measurement accuracy criteria related to the state II order levelling networks constituted with original and reduced levelling measurements. Levelling lines of two levelling networks of the II order, on the area of two deliberately selected and representative levelling loops of the Croatian state levelling network of I order, were analyzed. An accuracy criterion, using the original measurements and comparatively using the reduced measurements from their survey epoch to the I order network surveying epoch, is determined. Comparative comparison of the original and reduced measurement accuracy criteria is not clearly and unequivocally confirmed, nor completely rejected, the adequacy of the kinematic model quality for measurement reductions determination. However, comparison points to the fact that the quality of the kinematic model enables reliable determination of the relative height displacements at the centimeter level. [ABSTRACT FROM AUTHOR]