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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.

A method that gives the clearest individual geomorphometric elements for the requirements of spatial analysis was selected to define the spatial variability of landforms on primary bedrocks and their slope deposits on the northern edge of the Vipava Valley in Slovenia. We tested the most frequently used morphometric indicators of surface roughness, other than the curvature of the surface, and reviewed them based on their performance with lidar data. We analysed in detail five methods that can be used for surface roughness evaluation and that have a potential for the study of the bedrock and slope deposits. Height variability was identified as the most appropriate method. We have also found that maps of properly portrayed height variability can be an indispensable tool for geological and geomorphological mapping.

Pomembno težo pri razumevanju dogodkov današnjih plazov ima tudi raziskovanje fosilnih plazov, ki so nastali v bližnji in daljni geološki preteklosti. Fosilni, predvsem subrecentni plazovi opozarjajo na labilna in potencialno nevarna območja, na katera moramo biti pozorni še danes. Edinstven vpogled v različne pobočne procese v naravi, kjer lahko ob hkratnem raziskovanju značilnosti sedimentov fosilnih plazov opazujemo tudi aktivnost recentnih procesov plazenja, nam prav gotovo nudi območje Rebrnic. Pobočne grušče na območju Rebrnic so opisali in kartirali številni avtorji, nihče pa se ni podrobno ukvarjal z mehanizmi transporta in sedimentacijskimi procesi kvartarnih pobočnih sedimentov. V doktorski disertaciji je predstavljena raziskava pobočnih gruščev, izvedena z geološkogeomorfološkim pristopom. Z vizualno interpretacijo senčenega modela reliefa in kazalnikom hrapavosti površja, izračunani iz podatkov aero laserskega skeniranja, so v kombinaciji z geološkim kartiranjem večinoma zelo dobro identificirani tako oblika, kot tudi razširjenosti in lastnosti površja posameznih sedimentnih teles. Na podlagi litoloških, stratigrafskih in arhitekturnih značilnosti pobočnih sedimentov je bilo ločeno 16 faciesov, ki označujejo končne člene raznolikih sedimentacijskih procesov znotraj kompleksnih in pogosto prepletenih ter medsebojno odvisnih mehanizmov transporta. Rezultati, navedeni v tem delu, ter celosten pregled dostopnih podatkov in literature so omogočili razumevanje mehanizmov transporta in sedimentacijskih procesov kvartarnih pobočnih sedimentov na območju Rebrnic ter s tem omogočili nov vpogled v pobočna premikanja na celotnem severnem robu Vipavske doline. In order to understand the gravity process of recent landslides it is important to explore fossil landslides, which occurred during the near and distant geological past. Fossil, especially sub recent landslides can show us unstable and potentially dangerous areas to which we should pay attention today. A unique insight into different slope processes in nature is certainly Rebrnice area, where you can research the characteristics of the fossil landslides while observing the activity of the recent landslidess. The slope deposit in the Rebrnice area were described and mapped by many authors but nobody has covered the transport mechanisms and depositional processes of quaternary slope deposit in detail. This doctoral thesis presents the study of slope deposit elaborated with the geologicalgeomorphological approach. With the visual interpretation of the shaded digital elevation model and indicator of surface roughness, which are calculated from the data of airborne laser scanning in the combination of geological mapping, we can in most cases clearly identify the form of the prevalence and surface characteristics of individual sedimentary bodies. On the basis of the lithological, stratigraphic and architectural characteristics of the slope deposit 16 facies were separated, indicating the final articles of diverse sedimentary processes within complex and often interlaced and interdependent transport mechanisms. Results described in this work, and a comprehensive review of the available data and literature have made it possible to understand the transport mechanisms and the depositional processes of quaternary slope deposit in the Rebrnice area and thereby allow new insight into slope movement throughout the northern area of the Vipava Valley.

Na območju Rebrnic, ki se nahajajo na severovzhodnem pobočju Zgornje Vipavske doline, so odloženi sedimenti številnih recentnih in fosilnih poligenetskih plazov. Na tem območju so mezozojski karbonati Hrušiškega pokrova narinjeni na terciarne flišne kamnine Snežniškega pokrova. Matično podlago Rebrnic predstavljajo meljevci, peščenjaki, laporovci in redke debelejše kalciturbiditne plasti. Čez flišno podlago so odloženi stratificirani, po sestavi kompleksni kvartarni nanosi. Plazovi na tem območju so nastali z različnimi mehanizmi transporta in sedimentacijskimi procesi. Na pobočjih se pojavljajo sedimenti drobirskih in blatno-drobirskih tokov in plazov, zrnskih tokov, kot tudi globokih rotacijskih in rotacijsko translacijskih plazov. V okviru magistrskega dela smo analizirali plastnate karbonatne breče globokega rotacijskega plazu v zaledju sedimentnega telesa Šumljak 3, čigar posebnost je več odlomnih robov. Breče, ki gradijo plaz, nastopajo v plasteh z izmerjenim vpadom plastnatosti do 60°, kar nakazuje rotacije posameznih blokov. Breče so nastale kot posledica litifikacije materiala melišč, več odlomnih robov pa pomeni več sekundarnih rotacijskih plazov. Izdvojenih je bilo 10 blokov karbonatnih breč, vsem je bila izmerjena topografska višina, debelina paketa plasti in plastnatost na mestih, kjer je bila vidna. Na štirih lokacijah so bili odvzeti orientirani vzorci. Breče so močno porozne, pore so zapolnjene s karbonatnim vezivom, ki ponekod nastopa v obliki sige. Klasti so večinoma mikritni in neenakomernih velikosti, največje zrno iz odvzetih vzorcev meri okrog štiri cm. V vzorcih so bili opisani cementi, ki nastopajo kot vezivo v medzrnskem prostoru. V zbruskih so bile evidentirane do štiri generacije cementov. Pojavljajo se mikritni, mozaični, pasjezobi, mikrostalaktitni cement, mikrosparitni do sparitni obrobni cement, ponekod je prisotna tudi muljasta osnova, pojavljajo se tudi lehnjaki. V prvi generaciji vedno nastopa mikritni cement, ponekod je ob njem prisoten tudi mikrostalaktitni cement, običajno se ob njem pojavlja bela linija (mikrosparitni do sparitni obrobni cement), ki na videz ločuje mikritni in mikrostalaktitni cement v tretji generaciji povečini nastopa mozaični cement, običajno se prične kot drobnozrnat, velikost zrn pa proti sredini narašča v tretji generaciji nastopa tudi pasjezobi cement, kateremu velikost zrn ponekod tudi narašča proti sredini, v prisotnosti pasjezobega cementa mozaični cement predstavlja četrto generacijo v nekaterih zbruskih se pojavlja tudi muljasta osnova v drugi, tretji oziroma zadnji, četrti generaciji. Prisotni so tudi lehnjaki, ti vedno predstavljajo najmlajšo, četrto generacijo. Zrna v zbruskih so zelo raznolika, tako po velikosti kot sestavi, a so izključno karbonatna. Rebrnice area lies on the NE slopes of the Upper Vipava Valley. There are many slope deposits of recent and fossil polygenetic landslides. In this area, the Mesozoic carbonates of the Hrušica nappe are thrusted on the Tertiary flysch rocks of the Snežnik nappe. The base rocks of the Rebrnice are marls, sandstones and rare calciturbidite layers. Overlying the flysch bedrock are stratified, complex Quaternary deposits. In this area, landslides were formed through various transport mechanisms and deposition processes, which include sediments of debris flow and avalanche, grain flow and also deep-seated rotational and translational landslides. In my master’s thesis I have been discussing the Quaternary deposits, especially slope screes and gravels. The stratified carbonate breccias of the deep – seated rotational landslides in the hinterlands of the Šumljak 3 sedimentary body were analysed. The Šumljak 3 sedimentary body is defined by several steep scarps, which define the border of the body. The breccia appears in layers with an inclination of up to 60°, which indicate the rotation of separate breccia blocks. The breccia was formed as a result of partial lithification of the talus, multiple escarpments indicate multiple rotational landslides. Ten blocks of carbonate breccia were identified and their height and layering, where visible, was measured. Porosity was observed at the macroscopic level, the pores being mostly filled with carbonate cements, occasionally in the form of a dripstone. The clasts are mostly composed of micritic cements and they are of irregular shape. The largest grain from the taken samples measures about four cm. I have described cements that appear as binders inside the pores. Up to four generations of cements were recorded. The cements occuring in the samples are: micritic, microstalactitic, mosaic, microsparite and sparite, ''dog-toothed'', mud matrix and tufa. The first generation is always represented by micritic cement, outgrown with microstalacitic cement. These two are sometimes separated by a white line (microsparite or sparite cement). The third generation is usually represented by mosaic cement, which begins to grow fine grained, the size of the grains often increases towards the centre of the pore. The same goes with dog tooth cement, it also represents the third generation, in this case the mosaic cement growing out of the dog-tooth cement represents the fourth generation. Sometimes the muddy matrix appears in the second, third or fourth generation. Tufa is present occasionally and it represents the youngest, fourth generation. The grains vary greatly in size and composition, but they are composed entirely of carbonate.

Rudarska dejavnost je v Šaleški dolini prisotna že okoli 150 let in je kot takšna glavna eksogena preoblikovalna sila na tem območju. Najbolj očiten geomorfološki element delovanja premogovnika je ugrezanje površja, ki je prisotno na širšem območju izkoriščanja premoga. Ena od značilnih geomorfnih oblik procesa ugrezanja so površinske razpoke, ki nastajajo na obrobju deformiranega območja. Analiza in opazovanje teh razpok bi lahko prispevala k boljšemu upravljanju okolja na vplivnem območju Premogovnika Velenje. V diplomski nalogi smo ugotovili, da je mogoče s pomočjo analiz daljinskega zaznavanja prepoznati in spremljati razpoke ter območje ugrezanja. Z analizo digitalnih modelov višin (DMV), ki so bili posneti v različnih časovnih obdobjih, smo lahko določili meje ugrezninskega bazena ter določili vlogo površinskih razpok v njem. Te se pojavljajo znotraj bazena in gradijo njegov rob. Z analizo reliefne izoblikovanosti smo z različnimi metodami analizirali proučevano območje in pri tem uporabili senčeni model reliefa (ang. hillshade), razgibanost površja (ang. Terrain Ruggedness Index – TRI), topografski položaj (Topographic Position Index - TPI), usmerjenost pobočja (ang. Aspect) in hrapavost površja (ang. Roughness). Na osnovi analiz površja smo prepoznali razpoke in jih ločili od ostalih naravnih in antropogenih geomorfnih elementov na območju ter izdelali geomorfološko karto ugrezninskih elementov na območju šaleških jezer (območje v obliki pravokotnika s koordinatami ogljišč (WGS84): 15° 05' 33.77'', 46° 23' 25.90'' 15° 05' 33.69'', 46° 22' 37.32'' 15° 03' 13.35'', 46° 23' 26.00'' 15° 03' 13.30'', 46° 22' 37.41''). Z izdelavo različnih zemljevidov ter njihovo vizualno analizo je bilo ugotovljeno, da je za prepoznavanje in opisovanje posameznih ugrezninskih razpok najbolje uporabna analiza TRI. Pri tej metodi je razločevanje med hrapavimi geomorfnimi oblikami najbolj jasno, saj hrapavi elementi v primerjavi z drugimi metodami najbolje izstopajo. Vsekakor pa je mogoče razpoke dobro prepoznavati tudi s pomočjo ostalih produktov daljinskega zaznavanja, kot sta senčeni model reliefa in ortofoto posnetek. Mining has been present in the Šalek Valley for about 150 years and is therefore, the most important exogenous geomorphic force in the area. The most obvious geomorphological element in the valley is subsidence of the surface, which is present in the wider area of coal exploitation. One of the typical geomorphological forms of the subsidence process are the ground fissures that are formed at the outskirts of the deformed area. The analysis and observation of these cracks could lead to better environmental management in the influential area of the Velenje coal mine. In the diploma thesis, we found out that with the help of remote sensing products we can identify and monitor cracks and the subsidence basin. By analysing digital elevation models (DEM) recorded at different times, we were able to determine the boundaries of the subsidence basin and determine the role of ground fissures in this basin. With a number of DEM analyses, which are hillshade, Terrain Ruggedness Index-TRI, Topographic position Index-TPI, Aspect and Roughness, we identified cracks and separated them from other geomorphic elements in the area (natural and anthropogenic). The product was a geomorphological map of subsidence elements in the Šalek Lakes area (area in between coordinates (WGS84): 15° 05' 33.77'', 46° 23' 25.90'' 15° 05' 33.69'', 46° 22' 37.32'' 15° 03' 13.35'', 46° 23' 26.00'' 15° 03' 13.30'', 46° 22' 37.41''). Of all analyses, the identification of fissures proved TRI to be the best. However this works most effectively compared to other analyses, such as Senčen relief and TPI, Orthophoto imagery and DEM differences, if available.

Raziskovano območje se nahaja na jugozahodu Slovenije v Zgornji Vipavski dolini. Diplomska naloga zajema širše območje vojaškega strelišča Mlake, ki se nahaja ob hitri cesti H4 Razdrto–Vipava, pod strmim vznožjem na robu planote Nanos. Zaradi posebne geološke zgradbe obravnavanega območja, kjer so mezozojski karbonati narinjeni na mlajše paleogenske siliciklastične kamnine, prihaja do različnih tektonskih deformacij spodaj ležečih kamnin. Zaradi preperevanja karbonatnih kamnin se na pobočju proti dnu doline nanašajo obsežne količine gruščnatega materiala. Ker so grušči vodoprepustni, spodaj ležeče flišne kamnine pa slabše prepustne, se podzemna voda generalno pretaka po meji obeh navedenih horizontov. Leta 2008 je Slovenska vojska na območju Mlak zgradila novo strelišče, ki je s svojim severovzhodnim robom vkopano v pobočje. Kmalu po izgradnji so se začeli pojavljati problemi zamakanja posameznih objektov, saj podzemna voda ob vsakem močnejšem deževju, kljub vgrajenim jaškom in cevem za odvajanje meteorne vode poplavi posamezne dele strelišča. Z izvedbo terenskega dela in preučevanjem lege flišnih paketov kamnin ter pobočnega grušča v zaledju strelišča, sem poleg geoloških značilnosti preučil tudi geomorfološke značilnosti območja. Pri delu sem si pomagal z lidarskimi posnetki ter nadaljnjo obdelavo senčenega digitalnega modela reliefa v programu QGIS 3.4, kjer sem izdelal končno inženirsko-geološko in geomorfološko karto v merilu 1 : 7500. Izračunal sem sedanji volumen sedimentnega telesa fosilnega gruščnatega plazu, ki je odložen v zaledju strelišča. Rezultati raziskav kažejo, da je v okolici fosilnega plazu Mlake veliko izvirov vode, ki imajo morebiten vpliv na pritok v spodnjem delu plazu, kjer je strelišče vkopano v vznožje pobočja. Voda, ki zaliva strelišče prihaja tako iz tektonsko pretrtega fliša, kot tudi na meji z zgoraj ležečim pobočnim gruščem fosilnega plazu. The studied area is located in the Upper Vipava valley, in South-Western Slovenia. The research covered a wider area of the Mlake military shooting range, which is located near the H4 Razdrto–Vipava road at the foothills of mountain Nanos. Tectonic deformations in the underlying rocks occur due to the specific geological situation of the area, where Mesozoic carbonates are thrusted onto Paleogene siliciclastic rocks. The erosion of the carbonate rocks, in combination with steep slopes, causes extensive gravel deposits near the bottom of the Upper Vipava valley. The groundwater therefore prefers to flow at the boundary between the upper layers which consist of highly permeable gravel, and the lower flysch layers, which have low permeability values. In 2008, the Slovenian Army acquired a new shooting range in Mlake, which is dug into the slope at its North-Eastern corner. After each major rainfall event, despite the installation of drainage shafts and pipes, problems with rising groundwater level and, as a result, leaks occurred shortly after its construction. The geological and geomorphological characteristics of the area were determined through field mapping which included the study of the position and orientation of flysch and slope deposits at the edge of the Mlake shooting range. Lidar and digital elevation model processing techniques in QGIS 3.4 were utilized in the construction of the final geological-engineering and geomorphological map in the scale of 1 : 7500. To further complement the constructed map, I also calculated the current volume of the deposited fossil landslide that consists of gravel and is located at the edge of the Mlake shooting range. The results of the field work show a large number of springs located in the fossil landslide area. These springs could possibly represent an inflow of water into the lower parts of the landslide, exactly where the shooting range is dug into the foot of a slope. The water causing the flooding of the shooting range, originates from the boundary between the lower tectonically fractured less permeable flysch and the upper fossil landslide consisting of more permeable gravel.

The Post-Forum Study Tour following the 4th World Landslide Forum 2017 in Ljubljana (Slovenia) focuses on the variety of landslide forms in Slovenia and its immediate NW surroundings, and the best-known examples of devastating landslides induced by rainfall or earthquakes. They differ in complexity of the both surrounding area and of the particular geological, structural and geotechnical features. Many of the landslides of the Study Tour are characterized by huge volumes and high velocity at the time of activation or development in the debris flow. In addition, to the damage to buildings, the lives of hundreds of people are also endangered; human casualties occur. On the first day, we will observe complex Pleistocene to recent landslides related to the Mesozoic carbonates thrust over folded and tectonically fractured Tertiary siliciclastic flysch in the Vipava Valley (SW Slovenia), serving as the main passage between the Friulian lowland and central Slovenia, and thus also an important corridor connecting Northern Italy to Central Europe. A combination of unfavourable geological conditions and intense short or prolonged rainfall periods leads to the formation of different types of complex landslides, from large-scale deep-seated rotational and translational slides to shallow landslides, slumps and sediment gravity flows in the form of debris or mudflows. The second day of the study tour will be held in the Soča River Valley located in NW Slovenia close to the border with Italy, where the most catastrophic Stože landslide in Slovenia recently caused the deaths of seven people, and the nearby Strug landslide, which is a combination of rockfall, landslide and debris flow. The final day of the Post-Forum Study Tour will start in the Valcanale Valley located across the border between Slovenia and Italy, severely affected by a debris flow in August 2003. The flow caused the deaths of two people, damaged 260 buildings; large amounts of deposits blocked the A23 Highway, covering both lanes. In Carinthia (Austria), about 25 km west of Villach, the Dobrač/Dobratsch multiple scarps of prehistoric and historic rockslides will be observed. Dobratsch is a massive mountain ridge with a length of 17 km and a width of 6 km, characterized by steep rocky walls. The 3-day study tour will conclude with a presentation of the Potoška planina landslide, a slide whose lower part may eventually generate a debris flow and therefore represents a hazard for the inhabitants and for the infrastructure within or near the village of Koroška Bela.