Quaternary faulting in the western part of the Gulf of Corinth has been evidenced by geology and geomorphology, as well as by seismic recording. A series of three main normal fault segments are aligned in a steep southern coastal zone of the gulf. These fault segments, 15 to 25 km long, have an average strike of 90° - 105° and a northward dip of about 50° - 75°. Selected fault points were equipped with 3-D crack gauges TM71 during 2002 to monitor movements along the fault planes here, as well as on another fault cutting through the small island of Trizonia near the opposite northern shore of the gulf. Results of the monitoring present relative displacements induced by active tectonic movement s. Generally, the movements recorded on the faults are characteristic of an aseismic linear creep in vertical, i.e. upliftin g/subsiding in rates of mm per year due to uplifts of the Peloponnesian Peninsula. In 2003 a thr ee months long period of fast acceleration of movements was recorded. During this acceleration phase displacements changed to skew uplifting/subsiding with a left-lateral horizontal component. Moreover, horizontal rotation of monitored blocks corresponding to a sy stematic westwards opening of the Gulf was observed with only single eastward opening episodes., Josef Stemberk and Blahoslav Košťák., and Obsahuje bibliografické odkazy
The paper presents the results of geodyn amic research in the fram e of the project COST 625 relating to active tectonic structures’ monitoring on the selected areas in Poland, Italy and Greece. Research was realised using a self-developed control and measurement system. The resu lts of researches for period 2000-2006 indi cate slight movements of observatio n points in the Sudety Mts. reaching several millimetres. However, the results confirm recent mobility of tectonic structures o f this area. Research realised in the Mediterranean Region objects - Gargano, Norcia (Italy) and Kaparelli (Greece) - indicate movements of observation points reaching over a dozen millimetres, particularly on the Gargano area. Continuation of cyclic control measurements on these objects is fully justified ., Stefan Cacoń, Bernard Kontny and Jarosław Bosy., and Obsahuje bibliografické odkazy
Thessaly lies on the Aegean (micro-)plate, undergoing internal crustal deformation due to the plate relative motion against the adjacent Anatolian and Nubian plates. As a result, the whole Thessalian Basin was supposed to be under an extensional tectonic regime of N-S direction. However, the recent earthquake sequence of March 2021 which occurred close to the northwestern margin of the basin revealed NE-SW direction of extension. Based on 7-year GPS measurements recorded by stations installed within and around the basin we assessed four deformational parameters for Thessaly aiming at the understanding of the deformation processes that control the region. These parameters are i) the Maximum Horizontal Extension (MAHE), ii) the Total Velocity (TV), iii) the Maximum Shear Strain (MSS), and iv) the Area Strain (AS). The results show that during the monitoring period, Thessaly moved toward the S-SW with a simultaneous clockwise rotation and underwent dispersed deformation mostly associated with dilatation. Focusing on the epicentral area of the 2021 sequence, strain during the 7-year period was rather low in all three strain parameters, implying a mature stage of elastic strain accumulation before the fault rupture., Ilias Lazos, Sotirios Sboras, Konstantinos Chousianitis, Stylianos Bitharis, Evaggelos Mouzakiotis, Vassilios Karastathis, Christos Pikridas, Aristeidis Fotiou and Dimitris Galanakis., and Obsahuje bibliografii
Monitoring of tectonic movements along three active faults of Dinaric (NW-SE trending) fault system in W Slovenia using TM 71 extensiometers was set up in 2004. After two and a half years of measurements clear trends of displacement were recorded. The average left-lateral displacement along a crack in the inner fault zone of the Idrija fault in Učja valley was reading 0.38 mm/year. Short term (10 months) rates were even greater and reached the value of 0.54 mm/year. Since the Idrija fault is considered generally to be dextral strike-slipping, the observed left-lateral displacement can be explained by variations in principle stress. Raša fault monitoring site at the foot of Vremščica Mt. established an average reverse uplift of hanging wall (SW) block of 0.24 mm/year and left-lateral displacement of 0.16 mm/year. Short term (9 months) vertical displacements reached the value of 0.53 mm/year. The inclined displacement is in agreement with geological and seismological observations. In the Postojna cave system two instruments were installed at the fault which extends parallely to Predjama fault zone. The average vertical displacement rate at Postojna 1 site was 0.01 mm/year. Both devices recorded similar reaction which can be attributed to 12 July, 2004 (Mw=5.2) earthquake with an epicentre 70 km away from the measuring site. Since there were no other stronger earthquakes in the vicinity and time span of monitoring, no other correlations were established with earthquake activity. The observed displacement rates along all three monitored faults of up to 0.5 mm/year are consistent with the regional deformation rate in W Slovenia established from GPS measurements which is of the order of 2 mm/year., Andrej Gosar, Stanka Šebela, Blahoslav Košťák and Josef Stemberk., and Obsahuje bibliografii
UK-Slovenian collaborative research connected to EU COST-Action 625 began in 2003 and has involved interdisciplinary research into the current activity, structural architecture and landscape expression of the Ravne and Idrija strike-slip fault systems in NW Slovenia. The Ravne fault may be the best exposed actively propagating strike-slip fault system in Europe and through combined structural fieldwork, earthquake seismology and airborne LiDAR (Light Detection And Ranging) surveys, a new understanding of the fault’s along-strike segmentation, three dimensional geometry and stepover zone kinematics has been gained. The Idrija Fault in contrast, is poorly exposed, but defines a regional lineament with an intensely brecciated fault core; it may have been responsible for the largest historical earthquake to have ever affected the region. High-resolution LiDAR images recently obtained for both fault systems allow for efficient focussed fieldwork and future work will be devoted to documenting the timing of previous earthquakes and the connectivity and displacement transfer between active faults at the NE corner of the Adria microplate., Dickson Cunningham, Andrej Gosar, Vanja Kastelic, Stephen Grebby and Kevin Tansey., and Obsahuje bibliografii
This work presents the results of 3-D movements of faults occurring in the Dědičná štola gallery in the Rychlebské hory Mts. during the period between 2014 and 2017. The faults were monitored by TM-71 extensometers. The detected fault slip is nonlinear and is affected by short transient periods of acceleration. One dominant and a series of minor transient fault slip accelerations were recognised. The recorded accelerations were induced by switching two compressional stress/strain states – WNW-ESE to NW-SE compression corresponding to the stress field of the Western European stress domain and to NNE-SSW corresponding to the stress field of the NW part of the Carpathian stress domain. The extensional state, oriented NW-SE, corresponding to gravitational spreading due to the Rychlebské hory Mts. uplift, was recognised.
The broader Corinth Gulf region is characterized by a notable active tectonic regime, associated with multiple active fault zones. The continuous N–S extensional tectonics of the area is responsible for the roughly E–W trending active normal fault zones, while individual fault segments are associated with seismic events. Satellite geodesy is a qualitative and quantitative means of estimating the tectonically active setting, based on the recorded motions. The study area is monitored by 14 permanent GPS/GNSS stations, collecting primary geodetic data for a 7-year time period (2008-2014). A 30-sec observation rate was performed, resulting in the extraction of the GPS/GNSS velocity values. The primary geodetic data were processed by applying the triangulation methodology, based on the combination of three different GPS/GNSS stations data, which were considered as the triangle vertices. Triangulation methodology led to the construction of 26 different triangles, while for each of them a series of parameters was determined. In particular, the extracted parameters are: a) Maximum Horizontal Extension, b) Total Velocity, c) Maximum Shear Strain and d) Area Strain. The extracted results are expected to approach, qualitatively and quantitatively, the interpretation of the tectonic regime, as well as to determine new, seismic-related, tectonic features.