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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. [ABSTRACT FROM AUTHOR]

Abstract Glaciokarst depressions are major glacigenic depocenters in the Dinaric mountain karst areas and often store important information about the timing and nature of glacial processes and paraglacial sediment reworking. This study focuses on Praprotna draga, which is one of the largest glaciokarst depressions in the Snežnik Mountain (Dinaric karst), with an area of ~3.4 km2 and a maximum depth of 140 m. The western slopes of the depression are characterized by undulated moraine morphology and alluvial fans are filling its entire floor. We present the results on the thickness, origin and age of the sediment infill using a complementary geomorphological, sedimentological, geophysical and dating approach. Distribution of moraines point to two glacial advances that were associated with two main alluvial fan aggradation phases recognized using the electrical resistivity tomography measurements. The youngest alluvial deposits were sampled for cosmogenic 36Cl analysis using amalgamated carbonate pebbles. The depth profile of 36Cl concentrations suggests an age of 12.3 ± 1.7 ka when assuming a likely denudation rate of 20 mm ka−1. Since the existence of the Younger Dryas glaciers in the study area is climatically difficult to explain, we tentatively propose that the youngest alluvial deposition in Praprotna draga took place after the glacier retreat during the paraglacial period. Our findings suggest that the time window of paraglacial adjustment in the Snežnik Mountain was brief and likely conditioned by quick recolonization with vegetation and inefficient surface runoff on deglaciated karst terrain. Graphical abstract Unlabelled Image Highlights • The topmost ~2 m of alluvial deposits (AD2) was dated to 12.3 ± 1.7 ka. • Dated alluvial deposits are most likely of paraglacial origin. • Time window of paraglacial response to the last deglaciation in Snežnik was short. • Brief paraglacial response a result of karst drainage and quick vegetation change [ABSTRACT FROM AUTHOR]

Abstract The distribution of rock glaciers is often used to investigate the occurrence of permafrost in mountain areas and to understand their climate and paleoclimate evolution. This requires the creation of regional and global inventories capable of discriminating active and relict landforms in order to forecast the presence or absence of ice in the ground. In this paper, geomorphological, geophysical and microclimatic surveys are performed on a rock glacier of the Carnic Alps (Eastern European Alps). In the classification currently used for implementing regional inventories of permafrost evidence in the Alps, this rock glacier would be defined as relict. However the geophysical, climatological and geomorphological results indicate that internal ice is widespread in large portions of the rock glacier. These are generally interpreted as ice in pore spaces and local ice lenses, probably without layers of massive ice. Moreover the occurrence of ice during the maximum thawing season at depths <15 m, assumed here as the depth of zero annual amplitude, suggests that the ice occurring within the rock glacier is related to current cryotic conditions due to density driven air flow (i.e. the chimney effect). This research demonstrates that the current altitudinal limit of alpine permafrost can be locally several hundreds of meters lower than forecasted by empirical modeling based only on the rock glacier distribution and classification. Therefore, rock glacier classifications based only on remote sensing and geomorphological evidence as the main sources for extracting regional climate and paleoclimate signals should be treated with caution. Graphical abstract Unlabelled Image Highlights • Surveys on a rock glacier, supposed relict by using the current classification • Internal rock glacier's characterization trough ERT investigations • Resistivity values trough ERT investigations are typical of active rock glaciers. • Shallow Zero Annual Amplitude due to current ground cryotic conditions • Relevant residual ice at much lower elevation than the modelled permafrost limit [ABSTRACT FROM AUTHOR]