Search Results (5)

On 22 April 2022, a M_w 5.7 earthquake was generated near Stolac (Bosnia and Herzegovina). The mainshock was succeeded by several aftershocks, three of which were significant. Two M_b 4.3 earthquakes occurred on 23 April 2022, and a M_w 4.8 earthquake was generated on 24 April 2022. Available data from fault mechanism solutions revealed that the mainshock activated a reverse fault, while the aftershock generated a normal fault with a right-lateral component. The Balkan Peninsula stands as one of the most active geodynamic areas in Central and Eastern Europe due to its location within the collision zone between Eurasian and African tectonic plates and the Anatolian microplate. Recorded earthquakes in Bosnia and Herzegovina are related to the energy generated by the subduction of the African tectonic plate under Eurasia. Furthermore, the seismicity of Bosnia and Herzegovina, particularly its southern part, is profoundly influenced by the subduction of the Adriatic microplate under the Dinarides. The Dinarides are a mainly fold and thrust belt that extends from the Southern Alps in the northwest to the Hellenides in the southeast and make dominant the tectonic system of Bosnia and Herzegovina. In this study, two pairs of SAR images obtained from the Sentinel-1 satellite mission were utilized to generate satellite LOS surface displacements using the DInSAR method. Moreover, LOS displacements were decomposed into vertical and east–west horizontal components by combining ascending and descending satellite orbits. Ultimately, the InSAR results were analyzed and compared with the data obtained from the CROPOS CORS GNSS station in Metković (MET3). Full article

It is widely recognized that since the Early–Middle Pleistocene, the Messina zone, the site of strong earthquakes, has undergone extension, but the geodynamic context which determined this deformation is still a matter of debate. This work suggests that such a tectonic event was caused by the interaction of northern Calabria with the continental Adriatic domain. The suture of that consuming boundary produced major changes in the microplate mosaic and the related kinematic pattern in the Southern Italian zones, which was triggered by the activation of the Sibari and Vulcano faults. In the new context, the Peloritani belt sector, dragged by the Hyblean block, rotated clockwise and then moved northward, causing its divergence from southern Calabria. The normal faults which have accommodated that separation may be the main seismogenic source in the Messina Strait. Full article

Currently recognised lithospheric models hypothesise the non-existence of a lithospheric slab (a so-called slab gap) in the area of the Northern Dinarides, and the possible existence of a shallow slab in the Southern Dinarides. These geological models are mostly based on previous regional and global 3D velocity models obtained from teleseismic tomography. Recent local tomographic models providing a good resolution have regularly shown the existence of a fast anomaly underneath the entire Dinarides, directly indicating the existence of a lithospheric slab. To avoid interpretation pitfalls and increase reliability, forward seismic modelling based on new tomographic models was performed. Seismic modelling indicates a continuous lithospheric slab along the entire Dinarides in the shallow mantle, but it is not continuous vertically. In the Northern Dinarides, the shallow lithospheric slab extends at least to a depth of 150 km. In the Southern and Central Dinarides, there is a deep fast anomaly that can be interpreted in two ways due to the weak vertical resolution of teleseismic tomography. The first model suggests a steeply dipping continuous Adriatic lithospheric slab whereas the second model shows that the slab consists of two separate blocks, meaning that the deeper block was formed by delamination of the Adriatic lithospheric slab. Due to a similar correlation between the inverse velocity models for the synthetic model and the observed data, preference is not given to any model. The second model could indicate two independent Dinaridic subduction phases, as opposed to viewing subduction as a single long process during the geological past. Full article

The Adriatic microplate has always attracted scientific attention, and various studies on the geodynamics of this area have been performed over the years. With the development of global navigation satellite system (GNSS) technology in the last 30 years, most significant research in this field has used it as the primary source of data on geodynamic movements. However, apart from a few global positioning system (GPS) campaigns conducted in the 1990s, the measurements had a low spatiotemporal density. Therefore, the eastern side of the Adria region or the territory of the Republic of Croatia was usually omitted from the results presented in the various published papers. A study of this literature concluded that the territory of Croatia represents a kind of scientific gap and that denser measurement data from GPS/GNSS stations could be used to supplement the geodynamic picture of the area in question. Thus, GPS/GNSS measurements from 83 stations (geodynamic, reference, and POS’ GPS/GNSS) all over Croatia and neighboring countries for a period of almost 20 years (1994–2013) were collected and processed with Bernese software to obtain a unique database of relative velocities. From the geological perspective, the most important and latest insights on the recent geological structural setting, tectonic movements, most active faults, and relationships and movements of structures were taken into account. It was important to compare the geodetic and geological data, observe the present tectonic dynamics of the geological structural setting, and determine the causes of the obtained directions of movement. The research presented in this paper, based on a combination of geodetic and geological data, was conducted to broaden the current knowledge of the present tectonic dynamics of the geological structural setting of the eastern part of the Adriatic region. Full article

A quite energetic seismic excitation consisting of one main and three additional distinctive earthquake clusters that occurred in the transition area between the Kefalonia Transform Fault Zone (KTFZ) and the continental collision between the Adriatic and Aegean microplates is thoroughly studied after the high-precision aftershocks’ relocation. The activated fault segments are in an area where historical and instrumental data have never claimed the occurrence of a catastrophic (M ≥ 6.0) earthquake. The relocated seismicity initially defines an activated structure extending from the northern segment of the Lefkada branch of KTFZ with the same NNE–SSW orientation and dextral strike slip faulting, and then keeping the same sense of motion, its strike becomes NE–SW and its dip direction NW. This provides unprecedented information on the link between the KTFZ and the collision front and sheds more light on the regional geodynamics. The earthquake catalog, which was especially compiled for this study, starts one year before the occurrence of the M_w5.4 main shock, and adequately provides the proper data source for investigating the temporal variation in the b value, which might be used for discriminating foreshock and aftershock behavior. Full article