The northern slopes of the Vipava Valley are defined by a thrust front of Mesozoic carbonates over Tertiary flysch deposits. These slopes are characterized by a variety of different surface forms, ...among which recent and fossil polygenetic landslides are the most prominent mass movements. We used the height variability method as a morphometric indicator, which proved to be the most useful among the various methods for quantifying and visualizing fossil landslides. Height variability is based on the difference in elevations derived from a high-resolution lidar-derived DEM. Based on geologic field mapping and geomorphometric analysis, we distinguished two main types of movements: structurally induced movement along the fault zone and movements caused by complex Quaternary gravitational slope processes. The most pronounced element is the sliding of the huge rotational carbonate massif, which was displaced partly along older fault structures in the hinterland of fossil rock avalanches and carbonate blocks. In addition to the material properties of the lithology, the level of surface roughness also depends on the depositional processes of the individual sedimentary bodies. These were formed by complex sedimentary events and are intertwined in the geological past. The sedimentary bodies indicate two large fossil rock avalanches, while the smaller gravity blocks indicate translational–rotational slides of carbonate and carbonate breccia.
We present a geomorphological map on a scale of 1:15,000, with detailed sedimentological descriptions, and a general relative spatio-temporal depositional reconstruction of Quaternary sediments in ...the Planica-Tamar Valley (NW Slovenia). After the Last Glacial Maximum, the retreating Quaternary glacier deposited large amounts of glacial sediments. These were followed by Holocene sediments, which differ in their sedimentological characteristics, transport mechanisms, and morphology. These sediments are deposited as sedimentary bodies with complex depositional geometries. They form areas of active, partly active, and inactive sedimentation in response to local/regional climate and bedrock geology. Previous research of the valley was mainly focused on bedrock mapping, while almost completely neglecting Quaternary deposits. This work is the first broader analysis of Quaternary sedimentary deposits in the research area, which offers an insight into the complex geomorphological and sedimentological processes, which shape the current mountainous landscape.
The study area is located in cental Slovenia, and geologically located at the junction between the Alps and the Dinarides. The Middle Triassic of this region is characterised by intense rifting ...manifested by differential subsidence and volcanism. This led to a major paleogeographic reorganisation of the region, where three paleogeographic domains formed in the Upper Triassic: The Julian Carbonate Platform in the north, the intermediate Slovenian Basin, both parts of the Southern Alps, and the Dinaric (Adriatic, Friuli) Carbonate Platform in the south, which today is a part of the External Dinarides that host the area of investigation. Prior to the installation of the Dinaric Carbonate Platfrom, i.e. in the Ladinian, the entire area of the preset-day External Dinarides broke up into numerous tectonic blocks that were exposed to either erosion or continental, shallow-marine, and deep-marine sedimentation. In this study, we analyse at small scale a complex transitional area between a local carbonate platform and the Kobilji curek basin (depositional area dominated by deeper marine sediments), located in the Rute Plateau in central Slovenia south of Ljubljana. During enhanced subsidence, the basin was filled with volcanic material (tuffs and volcanogenic clays and subordinate extrusive material), while the adjacent platform aggraded. The slope was positioned above active paleofaults. During relative sea level lowstand, the platform prograded across the basin. The study area is divided into four major tectonic paleoblocks. The NW paleoblock experienced the most enhanced subsidence, and the platform prograded twice in this area and was submerged again by the rejuvenated subsidence and/or sea-level rise. The second and third paleoblocks subsided only during discrete major subsidence events, and the carbonates of the platform and slope were soon reinstated therein. In the fourth paleoblock to the east the platform persisted during the Ladinian. In the Carnian, the entire study area became emerged, and continental clastics were deposited. These were then replaced by a uniform shallow marine/intertidal Hauptdolomit (Dolomia Principale) formation at the onset of the Norian. This study provides the first detailed reconstruction of the sedimentary evolution of small-scale Ladinian basin and platforms system in the northern External Dinarides.
The area of Lokavec in the Vipava Valley, SW Slovenia, consists of Mesozoic carbonates thrust over Paleogene siliciclastic flysch. Overthrusting and tectonic damage of carbonates accelerated their ...mechanical disintegration. As a result, accumulations of slope gravel and large carbonate gravitational blocks are deposited on the slopes. Based on previous research, basic geological mapping and analysis of the DEM, ten carbonate blocks were identified. The aim of our research was to map lithology, measure and analyse the dip of carbonate strata and to determine transport mechanisms for individual blocks. The displacement of blocks from the source area ranged from 80 m to 1950 m. With the displacement of gravitational blocks, changes in dip direction and dip angle were also observed. The differences between the strata dip of carbonate source area and gravitational megablocks are from 4° to 59°.
The Julian Alps are composed almost exclusively of Triassic to Lower Jurassic carbonates, which results in a karstified high-alpine landscape. In such settings, large water accumulations are not ...expected and precipitated water drains vertically, gathers in deep, large-scale aquifers, and outflows in large karstic springs located in deeply incised valleys. Some small lakes, however, exist in high alpine areas. Most commonly, they formed above impermeable glacial sediments and are generally characterized by stagnant waters. Jezero v Ledvicah lake, which is one of the seven lakes in the Triglav Lakes Valley, is an exception, because it shows high subaqueous water inflow and outflow and occurs among highly karstified and permeable carbonates. Combining previous research with our new, detailed geological mapping of the lake surroundings and sedimentary research on the Lower Jurassic strata, we propose a hydrogeological model with the aim of explaining the extraordinary behaviour of the lake. We propose that Jezero v Ledvicah lake: A) is part of the "guttershaped" aquifer with perched groundwater that is situated below the floor of the Triglav Lakes Valley; B) barriers of the aquifer are structural (faults and thrust) and stratigraphic (clay interlayers in Lower Jurassic limestone); C) the lake formed in a structural, hydrogeological and morphological depression within this aquifer; D) the groundwater of the aquifer is recharged not solely from the surface directly above the aquifer but additionally by subterraneous inflow from the overlying Slatna Nappe aquifer; and E) groundwater outflows from the aquifer at the southern end of the Triglav Lakes Valley, where the Lower Jurassic limestone pinches out.
Hillshaded digital elevation models are a well-known information layer used to determine the geomorphological properties of landslides. However, their use is limited because the results are dependent ...on a particular sun azimuth and elevation. Approaches proposed to overcome this bias include positive openness, sky-view factor, red relief image maps, and prismatic openness. We propose an upgrade to all these methods, a method named Visualization for Archaeological Topography (VAT). The method is based on a fusion of four information layers into a single image (hillshaded terrain, slope, positive openness, and sky-view factor). VAT can be used to enhance visibility of features of varied scale, height, orientation, and form that sit on terrain ranging from extremely flat to very steep. Besides this, the merits of VAT are that the results are comparable across diverse geographical areas. We have successfully tested the method for landslide recognition and analysis in five different areas in the Vipava Valley (SW Slovenia). Geomorphology of the area is very diverse and holds various types of mass movements. In contrast to classical hillshaded digital elevation models (DEMs), the geomorphological features of landslides obtained by the VAT method are very clearly seen in all studied mass movements.
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