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On a global scale, inventories and databases are gaining value and there is a demand for openly accessible and reusable data. Here presented GIS database of glacial geomorphological evidence is a compilation of all available glacial and other relevant data in the South-Eastern Alps and the Northern Dinaric Mountains in Slovenia, Italy and Croatia. The database contains the following elements: glacial landforms (e.g., moraines, cirques, erratic fields, kame terraces), non-glacial landforms relevant for the interpretation of the glacial environment (e.g., alluvial fans, alluvial terraces, rock glaciers, protalus ramparts, talus cones), outcrop locations, geochronological data, and data on geophysical exploration. The accompanying attribute tables contains some basic information for each feature, such as type and description of a landform, assumed age, reference, etc. In the first step of database creation, the data were digitised, georeferenced (if not already done by the authors themselves) and cited accordingly. In the second step, the input data were revised in the field and topographically adjusted using a high-resolution lidar-based digital elevation model. The GIS database of glacial geomorphological data was used to develop the web map viewer, which also displays empirically reconstructed ice limits for different time spans during the last glacial cycle (130-0 ka). The data stored in the GIS database is available as ESRI shapefile format. Both the GIS database and the map viewer are open access. Disseminating the results of past and ongoing studies on glacial geomorphological evidence in the Alps-Dinarides junction will improve the availability and accessibility of data, build on previous findings and potentially prevent unnecessary repetition of work already done. Improved accessibility of data also offers greater potential for further research in large-scale studies in the area. This work was funded by the Past climate change and glaciation at the Alps-Dinarides junction project (J1-2479) supported by the Slovenian Research Agency.

On February 28, 2020 at 09:30:32 UTC, a daytime superbolide was observed over southeastern Slovenia and neighbouring countries1. In the following days, three meteorite pieces (469, 203, and 48 grams)2 were recovered nearby the Slovenian city of Novo Mesto by local people. The meteorite was classified as an L5 ordinary chondrite, more or less brecciated and shocked. In this work we reconstruct the trajectory using the available video data which consist of two static security cameras and four dash cameras mounted on cars in motion (Figure 1). We use a new radial distortion method developed by Vida et al. (2021) to accurately model the lens distortion of individual cameras and we determine the position of the vehicles to a precision of several centimetres on every video frame. Figure 1. Map of observer locations and the fireball trajectory (red line). The preliminary trajectory was computed using the lines of sight method and the trajectory uncertainties were computed using the Monte Carlo method (Vida et al., 2020) by adding 3σ noise to the original measurements. The fireball was first observed at a height of 68.7 km and it reached an end height of 17.1 km. The fireball had an entry angle of 47.812° ± 0.096° and an initial velocity of 22.098 ± 0.012 km/s (computed using measurements above 45 km, i.e. before any noticeable deceleration was visible). Figure 2 shows that the average per-station trajectory spatial fit errors were around 100 m (200 m maximum). More observations will be included in a future analysis. Figure 2. Spatial trajectory fit residuals. The Tkon and Senj stations were fixed security cameras, but only Tkon was calibrated on stars. The fireball had the following geocentric radiant (J2000): R.A. 330.920 ± 0.095 deg Dec +2.320 ± 0.098 deg VG 18.991 ± 0.014 km/s LG 333.802 ± 0.093 deg BG +13.319 ± 0.103 deg The computed orbit is: La Sun 338.983613 deg q 0.5679 ± 0.0011 AU a 1.451 ± 0.004 AU e 0.60866 ± 0.0006 i 8.755 ± 0.063 deg peri 82.649 ± 0.184 deg node 338.993041 deg T 1.7473 ± 0.0072 years TJ 4.4156 ± 0.0091 A parent body search returned a match for a few objects, depending on the used D criterion. The Potentially Hazardous Asteroid 2005 OX had the Southworth & Hawkins (1963) DSH criterion value of 0.078, while the Drummond (1981) criterion had close matched for asteroids 2008 DK5 (DD = 0.043), 2004 DF2 (DD = 0.050), and also 2005 OX (DD = 0.058). Possible connection to these objects may be a topic of future work, although these correlations might be spurious as the orbital parameter space is dense in that region. The fireball was bright enough to be picked up by the US government sensors3 which measured a total radiated energy of 11.5×1010 J. Assuming a typical L chondrite bulk density of 3620 kg/m3, we estimate that the meteoroid had an initial mass of 470 kg, corresponding to a diameter of about 0.63 m. We use the energy estimate to scale the observed light curve using the luminous efficiency of Borovička et al. (2020) – it compares well to an empirically derived light curve using a light source of known magnitude (reflection of the Sun from a chromium sphere at various distances). The fireball had one major fragmentation event at the height of 35 km which was picked up by the seismographs in the vicinity. A total of 18 fragments were tracked on the videos after the main fragmentation. The dynamic mass analysis shows that the final mass of the largest fragment was on the order of 10 kg. This rather large fragment has not been found yet – it is possibly buried into the soft ground and ploughed over. The fireball experienced fragmentations at dynamic pressures of 2.5, 3.5, and 10 Mpa, as shown in Figure 3. The peak dynamic pressure is the highest ever measured, after the the Benešov fall (Borovička et al., 1998). Figure 3. Left: Light curve measured on the Sesvete dash cam video. Blue curve is scaled using the CNEOS energy, and the orange curve was derived using the chromium sphere and the original dash camera. Middle: Velocity measurements and the Gritsevich (2007) model fit. Right: Dynamic pressures derived using the velocity fit and the NRL-MSISE00 air density model (Picone et al., 2002). Observed fragmentation points are marked with horizontal lines. The distribution of finds on the ground indicate that these meteorites were not produced at the end height but that some were ejected at several discrete heights above 20 km. Footnotes: 1AMS fireball report: https://fireball.imo.net/members/imo_view/event/2020/1027 2Meteoritical Bulletin Database, entry for Novo Mesto: https://www.lpi.usra.edu/meteor/metbull.php?code=72430 3CNEOS Fireballs: https://cneos.jpl.nasa.gov/fireballs/ References: Borovička et al. (1998). A&A, 334, 713-728. Borovička et al. (2020). AJ, 160(1), 42. Drummond, J. D. (1981). Icarus, 45(3), 545-553. Gritsevich, M. I. (2007). Solar System Research, 41(6), 509-514. Picone et al. (2002). Journal of Geophysical Research: Space Physics, 107(A12), SIA-15. Southworth, R. B., & Hawkins, G. S. (1963). Smithsonian Contributions to Astrophysics, 7, 261-285. Vida et al. (2020). MNRAS, 491(2), 2688-2705. Vida et al. (2021). The Global Meteor Network - Methodology and First Results. Submitted to MNRAS.

We present the compilation of a new database of active faults in Slovenia, aiming at introducing geological data for the first time as input for a new national seismic hazard model. The area at the junction of the Alps, the Dinarides, and the Pannonian Basin is moderately seismically active. About a dozen Mw > 5.5 earthquakes have occurred across the national territory in the last millennium, four of which in the instrumental era. The relative paucity of major earthquakes and low to moderate fault slip rates necessitate the use of geologic input for a more representative assessment of seismic hazard. Active fault identification is complicated by complex regional structural setting due to overprinting of different tectonic phases. Additionally, overall high rates of erosion, denudation and slope mass movement processes with rates up to several orders of magnitude larger than fault slip rates obscure the surface definition of faults and traces of activity, making fault parametrization difficult. The presented database includes active, probably active and potentially active faults with trace lengths >5 km, systematically compiled and cataloged from a vast and highly heterogeneous dataset. Input data was mined from published papers, reports, studies, maps, unpublished reports and data from the Geological Survey of Slovenia archives and dedicated studies. All faults in the database are fully parametrized with spatial, geometric, kinematic and activity data with parameter descriptors including data origin and data quality for full traceability of input data. The input dataset was compiled through an extended questionnaire and a set of criteria into a homogenous database. The final database includes 96 faults with 240 segments and is optimized for maximum compatibility with other current maps of active faults at national and EU levels. It is by far the most detailed and advanced map of active faults in Slovenia.

The 29 December 2020, Mw 6.4 Petrinja earthquake nucleated at a depth of ~10 km in the Sisak-Moslavina County in northern Croatia, ~6 km WSW of the Petrinja town. Focal mechanisms, aftershocks distribution, and preliminary Sentinel-1 InSAR interferogram suggest that the NW-SE right-lateral strike-slip Pokupsko-Petrinja fault was the source of this event.The Croatian Geological Survey, joined by a European team of earthquake geologists from France, Slovenia and Italy, performed a prompt systematic survey of the area to map the surface effects of the earthquake. The field survey was guided by geological maps, preliminary morphotectonic mapping based on 1:5,000 topographical maps and InSAR interferogram. Locally, field mapping was aided by drone survey.We mapped unambiguous evidence of surface faulting at several sites between Župić to the NW and Hrastovica to the SE, in the central part of the Pokupsko-Petrinja fault, for a total length of ~6.5 km. This is probably a minimum length since several portions of the fault have not been explored yet, and in part crossing forbidden uncleared minefields. Surface faulting was observed on anthropic features (roads, walls) and on Quaternary sediments (soft colluvium and alluvium) and Miocene bedrock (calcarenites). The observed ruptures strike mostly NW-SE, with evidences of strike-slip right-lateral displacement and zones of extension (opening) or contraction (small pressure ridges, moletracks) atlocal bends of the rupture trace. Those ruptures are interpreted as evidences of coseismic surface faulting (primary effects) as they affect the morphology independently from the slope direction. Ground failures due to gravitational sliding and liquefaction occurrences were also observed, mapped and interpreted as secondary effects (see Amoroso et al., and Vukovski et al., this session). SE of Križ, the rupture broke a water pipeline with a right-lateral offset of several centimetres. Measured right-lateral net displacement varies from a few centimetres up to ~35 cm. A portion of the maximum measured displacement could be due to afterlisp, as it was mapped several days after the main shock. Hybrid surface ruptures (shear plus opening and liquefaction), striking SW-NE, with cm-size left-lateral strike-slip offsets were mapped on the northern side of the Petrinja town, ~3 km NE of the main fault.Overall, the rupture zone appears discontinuous. Several factors might be inferred to explain this pattern such as incomplete mapping of the rupture, inherited structural discontinuities within the Pokupsko-Petrinja fault system, or specific mechanical properties of the Neogene-Quaternary strata

The earthquake with magnitude ML=6.2 that occurred on 29th December 2020 has caused significant material damage to objects and infrastructure in the towns of Petrinja, Sisak,Glina and the surrounding area. According to the satellite interferometry data, the coseismic and postseismic deformation area covers around 500 square kilometers. The existing geodetic benchmarks have been set in the affected towns, and their coordinates have been determined based on previous GPS campaigns. The GPS network was set up and adjusted at the State Geodetic Administration's request for geodetic monitoring of infrastructure and cadastral projects. These points are not primarily intended for high accuracy measurements at the level of a few millimeters, so their accuracy and the absolute shift concerning geodynamic processes in the region should be taken into account. Nevertheless, the data obtained by their observation after the earthquake can provide valuable information about the horizontal and vertical displacements with a certain level of confidence. The field survey has detected disappearance of a large number of benchmarks and some valuable information has been lost. Still, 58 points were found and observed and it has been concluded that 52 points are reliable and can be used for future research. Because the network of benchmarks is not developed in rural areas, there is a gap in the distribution of benchmarks in affected area. Therefore, the additional data was collected using the benchmarks established for the engineering and cadastral projects and studies. From a total of 67 points that have been found and observed, 42 points will be used. Along with the data collected in urban areas, there will be a total of 94 benchmarks. The accuracy of the geodetic benchmark measurements is at the centimeter level, while the values of deformation are at the level of a few decimeters. Therefore, the obtained data can be used to better assess the displacement recorded during the 29 December 2020 event. In the future, field research will focus on finding additional benchmarks to reach a better spatial distribution.

After the earthquake of 29/12/2020 in Petrinja (ML6.2, ImaxVIII-IX EMS), an attempt was made to characterize the active structure associated with the earthquake. As a first step towards this goal, we performed a geomorphological analysis in order to contribute to the identification and characterization of the surface expression of the active Pokupsko dextral strike-slip fault. We focused on the area between the southernmost parts of Vukomeričke Gorice and the southernmost parts of Hrastovica Mountain, where the NW-SE striking Pokupsko fault has slipped during and after the recent earthquake (Ganas et al., 2021). Using available 1 : 5 000 scale topographic maps and various 10 m resolution digital elevation model visualizations, we mapped lineaments that could represent relatively recently active fault segments. We used a quantitative approach to perform stream sinuosity analysis (e.g., Leopold et al., 1964; Zamolyi et al., 2010) on major streams crossing the structure to identify distinct changes in channel patterns that may be associated with vertical movement along the predominantly strike-slip fault. We observed changes in the shape of the valleys, especially the changes in width, height, and direction. By summarizing various geomorphological indicators of active fault segmentation at the surface with available geological data (Pikija, 1987) and so far limited field observations, we provide insights into the structure of the Pokupsko fault.Preliminary results show good agreement between lineament mapping, changes in valley shape, changes in the stream sinuosity index, and (to some extent) previously mapped faults. In addition, some of the changes in stream sinuosity correspond to locations where coseismic surface ruptures occurred during the December 29 earthquake (Budić et al., this session; Pollak et al., 2021). Results suggest that the several-kilometer-wide zone of uplifted Neogene deposits results from the dextral-transpressive structure, which at the surface consists of a series of subparallel fault strands branching off the main fault that runs along the SE slopes of the Hrastovica Mountain. The SW-most fault strands are associated with significant changes in the shape of the valleys: the wide valleys of Petrinjčica, Utinja and Šanja change to narrow and deeply incised as they cross the uplifted structure. Paleocene and Eocene rocks, which otherwise underlie the Neogene, outcrop in the NE parts of the fluvial breakthrough valleys, indicating the uplift of the Hrastovica Mountain. Topographic data show a decrease of the mountain range elevation towards the SW. This evidence suggests that the main fault runs on the NE side of the mountain, strikes NW-SE and dips steeply towards the SW. The fault strike deviates between Župić and Farkašić. The fault plane solution for the December 29 earthquake suggests a nearly pure strike-slip fault, while geomorphic evidence strongly indicates areas of active uplift along the fault, further supported by the general antiformal structure. We interpret this as an indication of either a general current transpressional character of the fault or as local kinematic variations due to segmentation and changes in the strike of the fault; further analyses are pending.

European Geosciences Union (EGU) General Assembly 2020, 4-8 May 2020, The H2020 Project SERA (WP25-JRA3; http://www.sera-eu.org) is committed to updating and extending the 2013 European Seismic Hazard Model (ESHM13; Woessner et al., 2015, Bull. Earthquake Eng.) to form the basis of the next revision of the European seismic design code (CEN-EC8). Following the probabilistic framework established for ESHM13, the 2020 update (ESHM20) requires a continent-wide seismogenic model based on input from earthquake catalogs, tectonic information, and active faulting. The development of the European Fault-Source Model (EFSM20) fulfills the requirements related to active faulting. EFSM20 has two main categories of seismogenic faults: crustal faults and subduction systems. Crustal faults are meant to provide the hazard model with seismicity rates in a variety of tectonic contexts, including onshore and offshore active plate margins and plate interiors. Subduction systems are meant to provide the hazard model with both slab interface and intraslab seismicity rates. The model covers an area that encompasses a buffer of 300 km around all target European countries (except for Overseas Countries and Territories, OTCs), and a maximum of 300 km depth for slabs. The compilation of EFSM20 relies heavily on publicly available datasets and voluntarily contributed datasets spanning large regions, as well as solicited local contributions in specific areas of interest. The current status of the EFSM20 compilation includes 1,256 records of crustal faults for a total length of ~92,906 km and four subduction systems, namely the Gibraltar Arc, Calabrian Arc, Hellenic Arc, and Cyprus Arc. In this contribution, we present the curation of the main datasets and their associated information, the criteria for the prioritization and harmonization across the region, and the main strategy for transferring the earthquake fault-source input to the hazard modelers. The final version of EFSM20 will be made available through standard web services published in the EFEHR (http://www.efehr.org) and EPOS (https://www.seismofaults.eu) platforms adopting FAIR data principles, The SERA project received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No.730900

The active landslide Slano blato above Lokavec in the Vipava valley, Slovenia, is a complex phenomenon. The hinterland of the landslide consists of the large fossil block of Mala Gora that slid about 300 m down the slope of Mt. Čaven, and was tilted with respect to the slope. We presume that the corresponding failure surface is concavelyshaped. The block consist in its lower part of Eocene flysch beds and in its upper part of Triassic carbonate rocks that are thrust over the flysch. It is probable that due to gravitational slumping the flysch basement obtained a concave shape, that serves as a catchment structure for retaining the ground water. It slowly percolates throughthe crushed calcarenitic layers in flysch. According to available data the Slano blato was triggered in 1887 by earthworks, and in 2000 by natural erosion processes. The structural characteristics allow the assumption that movement occurs in crushed and weathered flysch beds that are percolated by a steady or periodical supply ofgroundwater from the structural reservoir in the Mala Gora fossil slumped block. Coexistence of the older structural and the younger active weathered material landslides can be observed also at other localities along the thrust front of the Trnovo and Hrušica (Nanos) nappe. Especially interesting in this respect are the Razdrto and Strane landslides.

The Križevci H6 meteorite was recovered on the basis of fireball data obtained by the cameras of the Croatian Meteor Network. The fireball, which occurred on February 4, 2011, 23:20:40 UT, was also observed by meteor cameras in Slovenia and by the Autonomous Fireball Observatory in Martinsberg, Austria, which belongs to the European Fireball Network. Here, we present detailed data on fireball trajectory, velocity, deceleration, light curve, and orbit. We also modeled the atmospheric fragmentation of the meteoroid on the basis of the light curve and deceleration. The initial mass of the meteoroid was between 25–100 kg, most probably about 50 kg. Severe fragmentation occurred at heights of approximately 60 and 31 km, under dynamic pressures of 0.1 and 3 MPa, respectively. The peak absolute magnitude of 13.7 was reached during the second severe fragmentation event. The recovered 291 g meteorite was probably the only fragment with a terminal mass exceeding 100 g. The orbit had a low inclination of 0.6 degrees, perihelion distance 0.74 AU, and semimajor axis 1.54 AU. Križevci can be ranked among the 10 best documented meteorite falls.