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
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> 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 Input data was mined from published papers, reports, studies, maps, unpublished reports and data from the Geological Survey of Slovenia archives and dedicated studies.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 paper aims to present the geology of the western part of the Classical Karst (NW Dinarides), located at the border between Slovenia and Italy. The work is based on archive, published and new data ...collected by Slovenian and Italian researchers within several scientific national and Cross Border Cooperation projects. The map, produced at a scale of 1:50,000, summarizes the lithological and structural setting and is supplemented by three geological cross-sections of the study area.
Persistent scatterer interferometry (PSI) is capable of millimetric measurements of ground deformation phenomena occurring at radar signal reflectors (persistent scatterers, PS) that are phase ...coherent over a period of time. However, there are also limitations to PSI; significant phase decorrelation can occur between subsequent interferometric radar (InSAR) acquisitions in vegetated and low-density PS areas. Here, artificial amplitude- and phase-stable radar scatterers may have to be introduced. I2GPS was a Galileo project (02/2010–09/2011) that aimed to develop a novel device consisting of a compact active transponder (CAT) with an integrated global positioning system (GPS) antenna to ensure millimetric co-registration and a coherent cross-reference. The advantages are: (1) all advantages of CATs such as small size, light weight, unobtrusiveness and usability with multiple satellites and tracks; (2) absolute calibration for PSI data; (3) high sampling rate of GPS enables detection of abrupt ground motion in 3D; and (4) vertical components of the local velocity field can be derived from single-track InSAR line-of-sight displacements. A field trial was set to test the approach at a potential landslide site in Potoška planina, Slovenia to evaluate the applicability for operational monitoring of natural hazards. Preliminary results from the trial highlight some of the key considerations for operational deployments in the field. Ground motion measurements also allowed an assessment of landslide hazard at the site and demonstrated the synergies between InSAR and GPS measurements for landslide applications. InSAR and GPS measurements were compared to assess the consistency between the methods from the slope mass movement detection aspect.
EN: The northwestern part of the Ljubljana Basin is filled mostly with fluvioglacial sediments deposited by rivers coming from Alpine mountain groups. The Tržiška Bistrica River, flowing from the ...Karavanke Mountains, has deposited a large alluvial fan consisting predominantly of carbonate pebbles with subordinate amounts of siliciclastic pebbles. The oldest infill, cemented into a conglomerate terrace named Udin Boršt, overlies an erosional surface on Oligocene mudstone. The thickness of the conglomerate terrace is up to 50 m. The conglomerate terrace is well karstified; the surface is dissected by numerous dolines and covered with a thick soil sequence. There are several caves. The most important are spring caves formed on the contact with the underlying impermeable basement. Samples of quartz pebbles were taken from the walls and ceiling in the 815 m long spring Arneševa Luknja Cave for cosmogenic nuclides burial age dating. The calculated burial age yielded an age of 1.86 ± 0.19 Ma that gives (i) the age of the oldest known infill in the Ljubljana Basin and (ii) indicates the time of change of the sedimentary system in the Basin from erosion to deposition. The age of the Udin Boršt karst and caves is significantly younger. The age dates provide grounds for a first relatively firm estimate of the long-term tectonic uplift of the Udin Boršt terrace to be between 0.06 and 0.04 mm/yr. This tectonic uplift rate may be related to the activity of the regional Sava Fault. SLO: Severozahodni del Ljubljanske kotline pokrivajo večinoma fluvioglacialni sedimenti, ki so jih odložile reke iz alpskih gorskih skupin. Tržiška Bistrica, ki priteka iz Karavank je odložila velik vršaj. V njem prevladujejo karbonatni prodniki z manjšim deležem siliciklastičnih prodnikov. Ta najstarejša zapolnitev, sprijeta v konglomeratno teraso Udin boršt, leži na erozijskem površju oblikovanem v oligocenskih glinovcih. Debelina konglomeratne terase je do 50 m. Konglomeratna terasa je dobro zakrasela, površje pa je razčlenjeno z vrtačami in pokrito z debelo plastjo prsti. V njej je več jam, med katerimi so najpomembnejše izvirne jame, ki so se oblikovale na stiku z neprepustno podlago. V 815 m dolgi Arneševi luknji smo vzeli iz sten in stropa jame vzorec iz kremenovih prodnikov za določitev pokopne starosti prodnega zasipa s kozmičnimi nuklidi. Izračunana starost prekritja sedimentov je 1.86 ± 0.19 Ma. Ta datacija določa (i) starost najstarejše sedimentne zapolnitve v Ljubljanski kotlini in (ii) čas spremembe v sedimentacijskem sistemu kotline iz erozije v sedimentacijo. Starost kraških oblik in jam v Udin borštu je znatno mlajša. Starost sedimenta daje tudi osnovo za relativno trdno določitev tektonskega dviga terase Udin boršta na 0,06 do 0,04 mm/yr. Ta tektonski dvig je verjetno povezan z premiki ob regionalnem savskem prelomu.
We applied an interdisciplinary approach to analyze the late Quaternary activity of the Sava Fault in the Slovenian Southern Alps. The Sava Fault is an active strike-slip fault, and part of the ...Periadriatic Fault System that accommodated the convergence of Adria and Europe. It is one of the longest faults in the Southern Alps. Using high-resolution digital elevation models from lidar and photogrammetric surveys, we were able to overcome the challenges of assessing fault activity in a region with intense surface processes, dense vegetation, and relatively low fault slip rates. By integrating remote sensing analysis, geomorphological mapping, structural geological investigations, and near-surface geophysics (electrical resistivity tomography and ground penetrating radar), we were able to find subtle geomorphological indicators, detect near-surface deformation, and show distributed surface deformation and a complex fault pattern. Using optically stimulated luminescence dating, we tentatively estimated a slip rate of 1.8 ± 0.4 mm/a for the last 27 ka, which exceeds previous estimates and suggests temporal variability in fault behavior. Our study highlights the importance of modern high-resolution remote sensing techniques and interdisciplinary approaches in detecting tectonic deformation in relatively low-strain rate environments with intense surface processes. We show that slip rates can vary significantly depending on the studied time window. This is a critical piece of information since slip rates are a key input parameter for seismic hazard studies.