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Erosion is an important exogene process that can be found on almost all surfaces around the globe and Slovenian territory is no exception to the rule. The extent of the erosion is a result of various factors linked to the surface properties, such as land use type, vegetation type, and geomorphology and of the factors linked to the climate, such as the precipitation regime and the temperature oscilation. The paper focuses on the modelling of the mechanical erosion and the surface transport of particles due to surfiial waters. The aim of the research was to combine the RUSLE surface erosion method with a model of gully erosion. The combined approach successfuly models the erosion in the mountainous and karst areas. Due to its vivid geomorphology that results in various natural surface proceses the area of Bohinj municipality was chosen as an ideal case study for testing the joint methodology.

In this paper we introduce a landslide prediction system for modelling the probabilities of landslides through time in Slovenia (Masprem). The system to forecast rainfall induced landslides is based on the landslide susceptibility map, landslide triggering rainfall threshold values and the precipitation forecasting model. Through the integrated parameters a detailed framework of the system, from conceptual to operational phases, is shown. Using fuzzy logic the landslide prediction is calculated. Potential landslide areas are forecasted on a national scale (1: 250,000) and on a local scale (1: 25,000) for fie selected municipalities where the exposure of inhabitants, buildings and different type of infrastructure is displayed, twice daily. Due to different rainfall patterns that govern landslide occurrences, the system for landslide prediction considers two different rainfall scenarios (M1 and M2). The landslides predicted by the two models are compared with a landslide inventory to validate the outputs. In this study we highlight the rainfall event that lasted from the 9th to the 14th of September 2014 when abundant precipitation triggered over 800 slope failures around Slovenia and caused large material damage. Results show that antecedent rainfall plays an important role, according to the comparisons of the model (M1) where antecedent rainfall is not considered. Although in general the landslides areas are over-predicted and largely do not correspond to the landslide inventory, the overall performance indicates that the system is able to capture the crucial factors in determining the landslide location. Additional calibration of input parameters and the landslide inventory as well as improved spatially distributed rainfall forecast data can further enhance the model's prediction.

Alluvial (torrential) fans, especially those created from debris-flow activity, often endanger built environments and human life. It is well known that these kinds of territories where human activities are favored are characterized by increasing instability and related hydrological risk; therefore, treating the problem of its assessment and management is becoming strongly relevant. The aim of this study was to analyze and model the geomorphological aspects and the physical processes of alluvial fans in relation to the environmental characteristics of the territory for classification and prediction purposes. The main geomorphometric parameters capable of describing complex properties, such as relative fan position depending on the neighborhood, which can affect their formation or shape, or properties delineating specific parts of fans, were identified and evaluated through digital elevation model (DEM) data. Five machine learning (ML) methods, including a hybrid Euler graph ML method, were compared to analyze the geomorphometric parameters and physical characteristics of alluvial fans. The results obtained in 14 case studies of Slovenian torrential fans, validated with data of the empirical model proposed by Bertrand et al. (2013), confirm the validity of the developed method and the possibility to identify alluvial fans that can be considered as debris-flow prone.

In the frame of national research and innovation project MASPREM exposure maps of inhabitants, buildings and infrastructures to landslide occurrence were developed for five selected Slovenian municipalities. Maps represent an upgrade of the landslide susceptibility maps that were elaborated based on synthesis of analysis of event-based landslide inventory and field investigations. Exposure maps were developed for five municipalities: Bovec, La{ko, Slovenj Gradec, Trbovlje and Železniki. Exposure of inhabitants, construction and infrastructures to landslide occurrence was analysed using simple cross-analysis of landslide susceptibility maps at scale of 1:25,000 with locations of exposed elements. All analyses were conducted in the GIS with software tool ArcMap. Exposure maps, based on landslide susceptibility, were classified into six classes, with values ranging from one to six where class one represents areas with negligible exposure and class six areas with very high exposure to landslide occurrence. Exposure maps of selected municipalities provide the basis for further assessment of risk and consequentially better risk management.

The purpose of the paper is to give a short overview of international activities of Geological Survey of Slovenia (GeoZS) in the field of research and development in the period of past fifteenyears.The background of suchanover view is to present the range and scale of these activities at GeoZS to wider scientific public.In addition to the overview short description of each project will be given, its duration, relative financial frame,and sources of financing.Some trends of described activities will also be addressed.

From the early history of civilisation societies have been exposed to external factors. Probably no other factorshave influenced the development of societies and cultures more than geologically driven hazards or geohazards.With the evolvement of societies also the approaches to solving problems, related to geohazard, have developed.The complexity of mitigation and response measurements that tackle the contemporary geohazard problems demandsa long-term strategic approach that has to incorporate all segments of the society, from stake-holders andend-user groups to the experts. The management of geohazards is a public good and as such needs to be governedby a non-profit public body. The common mission of almost all geological surveys is to gather, manage and interpretgeologically related data for a wider public welfare. Geological surveys as public institutions represent a key rolein almost all components of the geohazard management process, from education and research, to data acquisition,processing, interpretation and decision support issues. With its knowledge regarding natural processes gatheredthrough decades GSO offers reliable and independent support in assessing and describing the phenomena (seismicactivities, mass wasting, water and soil pollution, excess or lack of trace elements in the soil, ground subsidence orheave, gaseous emanations and more), understanding the processes of activation, dynamics, transport, interactionwith media and living organisms, and predicting the possible scenarios in the future with emphasis on human exposureto given phenomena. Despite the fact that the value of the knowledge of the dynamic environment we live in isbeing tested literally on daily basis in Slovenia, its inclusion in everyday practice is still relatively negligible.

For the area of Slovenia (20.000 sqr. km) a debris-flow susceptibility model at scale 1 : 250,000 was produced.To calculate the susceptibility to debris-flow occurence using GIS several information layers were used such as geology (lithology and distance from structural elements), intensive rainfall (48-hour rainfall intensity), derivates of digital elevation model (slope, curvature, energy potential related to elevation), hydraulic network (distance to surface waters, energy potential of streams), and locations of sixteen known debris flows, which were used for thedebris-flow susceptibility models’ evaluation. A linear model weighted sum approach was selected on the basis of easily acquired spatio-temporal factors to simplify the approach and to make the approach easily transferable toother regions. Based on the calculations of 672 linear models with different weight combinations for used spatio temporal factors and based on results of their success to predict debris-flow susceptible areas, the best factors’weight combination was selected. To avoid overfitting of the prediction model, an average of weights from the first hundred models was chosen as an ideal combination of factor weights. For this model also error interval was calculated. A debris-flow susceptibility model at scale 1 : 250,000 represents a basis for spatial prediction of the debris-flow triggering and transport areas. It also gives a general overview of susceptible areas in Slovenia andgives guidance for more detailed research areas and further spatial and numerical analyses. The results showed that approximatelly 4 % of Slovenia’s area are extremely high susceptible and approximatelly 11 % of Slovenia’sarea of susceptiblity to debris-flows is high. As expected these areas are related to mountainous terrain in the NWand N of Slovenia.

The Slovenian territory is, geologically speaking, very diverse and mainly composed of sediments or sedimentary rocks. Slope mass movements occur almost in all parts of the country. In the Alpine carbonate areas of the northern part of Slovenia rock falls, rock slides and even debris flows can be triggered.In the mountainous regions of central Slovenia composed from different clastic rocks, large soil landslides are quite usual, and in the young soil sediments of eastern part of Slovenia there is a large density of small soil landslides.The damage caused by slope mass movements is high, but still no common strategy and regulations to tackle this unwanted event, especially from the aspect of prevention, have been developed. One of the first steps towards an effective strategy of struggling against landslides and other slope mass movements is a central landslide database, where (ideally) all known landslide occurrences would be reported, and described in as much detail as possible. At the end of the project of National Landslide Database construction which ended in May 2005 there were more than 6600 registered landslides, of which almost half occurred at a known location and were accompanied with the main characteristic descriptions.The erected database is a chance for Slovenia to once and for all start a solid slope mass movement prevention plan. The only part which is missing and which is the most important one is adopting a legal act that will legalise the obligation of reporting slope mass movement events to the database.

In the recent years radar interferometry (InSAR) has become an important tool in various studies. It can be used to produce accurate digital elevation models and observe small surface displacements. Differential interferometry (DInSAR) can detect movements in the radar look direction that are in the order of wavelength used, i.e. less than one centimetre with ERS data. In the presented study DInSAR has been used to observe surface movements in western Slovenia. Three ERS radar images have been supplemented with an external digital elevation model to produce three differential interferograms that temporally covered the Posočje earthquake, which happened on April 12, 1998. For the area around Bovec a land subsidence of approximately 0.5 cm has been observed; the largest movements detected exceeded 2 cm. DInSAR has been compared to the permanent scatterers interferometry (PSInSAR). Both methods are complementary and both have individual advantages and disadvantages.

Permanent Scatterer interferometry method has been used to observe subtle surface displacements in the north-western part of Slovenia between April 1992 and December 2000. The method proved to be very useful (at least) as indicator of the vertical component of relative tectonic displacements velocity and as the tool to detect co-seismic surface di-splacements. The preliminary displacements in the region (1mm/y about) have been estimated,yet at this stage they are to be taken with restrain.

Based on the extensive landslide database that was compiled and standardised at the national level, and analyses of landslide spatial occurrence, a Landslide susceptibility map of Slovenia at scale 1 : 250,000 was completed. Altogether more than 6,600 landslides were included in the national database, of which roughly half are on known locations. Of 3,257 landslides with known location, random but representative 65 % were selected and used for the univariate statistical analyses (χ2) to analyse the landslide occurrence in relation to the spatio-temporal precondition factors (lithology, slope inclination, slope curvature, slope aspect, distance to geological boundaries, distance to structural elements, distance to surface waters, flowlength,andlandcovertype)and inrelation to the triggering factors(maximum 24-h rainfall, average annual rainfall intensity, and peak ground acceleration). The analyses were conducted using GIS in raster format with the 25 × 25 m pixel size. Five groups of lithological units were defined,ranging from small to high landslide susceptibility.Also critical slopes for the landslide occurrence, other terrain properties and landcover typesthat are more susceptible to landsliding were defined. Among triggering factors critical rainfall and peak ground acceleration quantities were defined.These results were later used as a basis for the development of the weighted linear susceptibility model where several models with various factor weights variations based on previous research were developed. The rest of the landslide population (35 %) was used for the model validation. The results showed that relevant precondition spatio-temporal factors for landslide occurrence are (with their weight in linear model): lithology (0.3), slope inclinaton (0.25), landcover type (0.25), slope curvature (0.1), distance to structural elements (0.05), and slope aspect (0.05).

A very good landslide susceptibility prediction model was developed for the area in the perialpine region in the central western Slovenia. Using multivariate statistics the interactions between spatial factors and landslide distribution were tested, and the importance of individual factor to the landslide susceptibility was defined. On the basis of the statistical results several landslide prediction models were developed using the Analytical Hierarchy Process (AHP) method. These models gave very different results, with a prediction error ranging from 6,89 % to 31,8 %. As a final result of the research, weights of different spatial factors from the best models calculated with the AHP method were derived. The results showed that the lithology (31 % variance), the slope inclination (21,2% variance), land cover type (13,7 % variance), the terrain roughness (10,1 % variance), and the terrain curvature (8,6 % variance) play an important role in landslide susceptibility in general. Minor roles also play the distance to streams and the distance to structuralelements. These factors weights values were later used as input values in a simple linear weighted landslide susceptibility prediction model for the area in the Alpine region (north-western Slovenia). The fact is that the ideal weight’s value of a factor differs from area to area. Each original weight value used in the new (Alpine) model presented only the mean of the new weight’s range/distribution, which was used as an input to the linearmodel. The analysis of the ideal factors weights in the Alpine area included several analytical trials, where different factors with different weight distribution were used.Altogether, almost 65 000 different models were calculated and tested to the landslide distribution. The best prediction results gave the model, where lithology played the major role in the landslide susceptibility (30 %), slope inclination contributed less (22 %), andland cover type contributed 20 % to the landslide susceptibility. The terrain curvature contributed 16 % to the landslide susceptibility. The distance to streams 10 % and the distance to structural elements contributed 2 % to the landslide susceptibility. When the importance of the synchronism of strata dipping and slope aspect was tested, this factor showed to be very significant (18 % - 22 %). The application of calculated weights from one area into another showed that general principles of spatial factor significance do exist,although they differ in some extent. This proof could be effectively used for fast and relatively inexpensive assessments of landslide susceptibility predictions in the remote and inaccessible regions such as are Alpine areas, but one should always bear in mind thatsome site specific spatial factors, i.e. synchronism of strata dipping and slope aspect, also play an important role in the landslide susceptibility, especially in the steep areas.

Methodology was developed for estimation of geohazard induced by mass movement processes, taking the Bovec municipality as the case study area. The geohazard map in scale 1:25.000 as the final product is aimed to be directly applicable in spatial planning of local communities (municipalities). The requirements that were followed to achieve this aim were: expert correctness, reasonable time of elaboration, and easy to read product.Elaboration of the final product comprises four consecutive phases, of which the first three are done in the office: 1) synthesis of archive data, 2) probabilistic model of geohazard induced by mass movement processes, 3) compilation of phases 1 and 2 into the final map in scale 1:25.000. As the last phase, field reconnaissance of most hazardous areas is foreseen.

Rainfall plays an important role in the landslide triggering processes. Analyses of landslide occurrence in the area of Slovenia have shown that areas where intensive rainstorms occure (maximal daily rainfall for the 100 years period), and where the geologicalsettings are favourable, abundance of landslide can be expected. This clearly indicates the spatial and temporal dependence of landslide occurrence upon the intensive rainfall. Regarding the landslide occurrence, the intensity of maximal daily and average annual rainfall for the the 30 years period were analysed. Results have shown that daily rainfall intensity, which significantly influences the triggering of landslides, ranges from 100 to 150 mm, most probably above 130 mm. Despite the vague influence, if any at all,of the average annual rainfall, the threshold above which significant number of landslides occurs is 1000 mm.

A probabilistic model of slope mass movement susceptibility for the Bovec municipality in north-western Slovenia was developed based on the expert geohazard map at scale 1: 25.000 and several other relevant influence factors. For analytical purposes 10816 modelswere developed, 3142 for landslide susceptibility and 7674 for rockfall susceptibility. In both cases geology / lithology and slope angle showed to be the most important influence factors. Regarding landslides, additional important factors were land use and synchronismof strata bedding and slope aspect, and in the case of rockfalls additional important factor was synchronism of strata bedding and slope aspect.

Based on seismic reflection profiles recorded in the last ten years in the frame of the investigations for assessment of earthquake hazard at the location of the Krško nuclear power plant, and taking into account relevant geological and gravimetric data as well asresults of deep boreholes, two structural model of the pre-Tertiary basement in the Eastern part of the Kr{ko basin were constructed. In the first model the depth contours of the pre- Tertiary basement were drawn by hand, and in the second model the radial based functioninterpolation method was applied. In the Eastern part of the Kr{ko basin two depressions were distinguished. The Western one – Raka depression is smaller and shallower (max. depth of 1600 m), meanwhile the Eastern one – Globoko depression is larger and deeper(max. depth of 2050 m). In-between is a saddle at Drnovo where the pre-Tertiary basement lies at the depth of approx. 1000 m. Three-dimensional model will be used in further studies as is seismological modelling of the influence of the shape of the sedimentary basinon the seismic ground motion in case of an earthquake.

Landslide occurrence is governed by numerous spatial and temporal factors that can be divided into the causes and the triggers. Human interaction with the environment coincides mainly with the triggers, which are also of natural origin. For a better understanding of the causing factors, which mainly influence the spatial distribution, several methods based on GIS technology are used. Results, derived from these methods, define areas that are more exposed to triggering factors, consequencially also to human activity. Based on the results of the univariate analysis the landslide occurrence specifics of the classes of factors under observation were defined. The interactions among spatial factors were analysed with multivariate statistics and their relative contribution to landslide occurrence were defined. Results were finally presented in the form of probability map (hazard map), and the area of the western central part of Slovenia was divided into the danger zones using five degree scale.

More and more detailed spatial data enable the scientists more precise and detailed spatial analysis’ and with that the natural hazard risk assessment. The purpose of the paper was to determine the applicability of the geologic, topologic, climatic and hydrologicdata with the mentioned topic. For this purpose, the area of the central Slovenia was chosen, where 614 landslides were mapped. The influence of the spatial factors on the landslides was determined. The results showed that the most influential factor was lithology,followed by slope inclination, terrain curvature, distance from structural elements,distance from surface waters, aspect, and elevation. The critical angle of landslide occurence was determined at 9°.

Based on data of the Basic Geologic Map 1:100,000 and the new reambulation a new Geologic map of Slovenia 1:250,000 has been prepared. On the map 114 lithostratigraphic units were individualized. Also important geologic structures and regional faults are shown. All data were imported into the GIS environment that enables simple utilization of these geologic data. During reambulation numerous new data were acquired. They appear for the first time on the geologic map.

The purpose of the paper is to present the field data relational database, which was compiled from data, gathered during thirty years of fieldwork on the Basic Geologic Map of Slovenia in scale1:100.000. The database was created using MS Access software. The MS Access environment ensures its stability and effective operation despite changing, searching, and updating the data. It also enables faster and easier user-friendly access to the field data. Last but not least, in the long-term, with the data transferred into the GISenvironment, it will provide the basis for the sound geologic information system that will satisfy a broad spectrum of geologists’ needs.

Gathering and analysing of the geological data of a certain area is a procedure where various spatial data are related and processed. The aim of a geologist is to determine the model that will represent the natural conditions by its most and will help him solve relations between data. Usually geological data have various origins and are for the purpose of modelling merged, united or joined together. The result is a geologic map that forms a foundation for the comprehension of the real geological conditions of a given area.The paper presents conceptual and logical model of the geological maps in the GIS environment. Here characteristics of the database, the standard procedures for the data input and their quality control procedures are shown.