This doctoral thesis focuses on superficial sliding, creeping, excessive erosion, gully erosion and rockfall processes in the Dubračina river basin in Primorsko – Goranska County. The river basin is an overthrust zone of carbonate over flysch possessing all the geological, geomorphological and climate preconditions for the occurrence of superficial geodynamic (engineering-geological) processes, and it is also specific for being currently the only discovered area in Croatia where the surface contains very erodible dispersive soils resulting from flysch weathering. In general, the research had two main objectives: zoning of the research area according to susceptibility to a particular superficial process at a scale of 1:5000 by applying statistical bivariate methods known as “Information Value Method” (IVM) and “Frequency Ratio Method” (FRM) and determining whether the dispersiveness affects the degradation of engineering-geological soil properties. The applied research methods can be divided into field, laboratory and dataprocessing methods. Field methods were used for mapping and verifying superficial processes and superficial deposit sampling. Laboratory methods were used to determine: grain size distribution in the superficial deposit of the flysch valley located between carbonate cliffs, the concentration of sodium, potassium, calcium and magnesium cations in the soil extract, Atterberg limits and cohesion and internal soil friction angle, soil weathering model after the drying-wetting process, and the mineral composition of silt and clay fractions. In data processing, a digital high-resolution terrain model was analysed, laboratory research results were synthesized, and factor maps and superficial processes susceptibility maps were produced using GIS technology. A combination of topographic maps and a high-resolution terrain model applied for remote mapping resulted in high-quality and reliable inventories of superficial processes which represent the most important input for the analysis of terrain susceptibility to superficial processes. This does not apply to parts of terrain where slide and excessive erosion processes overlap and where, without terrain verification, it is impossible to establish with certainty whether the morphology was caused by sliding or excessive erosion. Even if it is established that it was caused by sliding, due to high soil erodibility, morphological characteristics of a landslide disappear very quickly in such terrains. Analyses have shown that dispersive soils can be classified as lean and fat clays. The soil dispersivity is unrelated to mineral composition which is very similar in dispersive and non-dispersive clays, and also has no impact on clay activity. The cohesion and internal friction angle values do not differ between dispersive and non-dispersive clays; however, dispersive clays exhibit a sudden loss of cohesion with increase of water content. The dryingwetting test results clearly show the difference between dispersive and non-dispersive clays because dispersive clays quickly disintegrate into mud after being immersed in water. Dispersive clays also affect the sliding process because the increase of water content causes a sudden loss of cohesion in the soil and complete degradation of material and mechanical properties, causing the appearance of weakened zones as the location where shear planes begin to form. Excessive erosion linked to dispersive clays on the surface of the terrain with extremely high sodium ion concentrations in pore water, as is the case on the western side of the badland in the Slani potok creek basin, is the reason for very low thickness of the superficial deposit. This explains why sliding is unlikely to occur in such areas. However, research has confirmed that excessive erosion and sliding can represent a joint geodynamic event on the slope, exactly in those parts where dispersiveness is not caused by extremely high sodium concentrations in pore water, enabling the development of a somewhat thicker superficial deposit above bedrock. It has been observed on the eastern side of the badland in the Slani potok basin. Based on laboratory research, six characteristic factor maps of the Dubračina river basin have been produced and used in the analyses of terrain susceptibility to superficial processes. These are maps of clay, silt, sand and gravel proportions in superficial deposit, the map of distance from the dispersive sample and the binary map of terrain surface dispersiveness, where the badland inventory represents dispersive areas. According to the results of the analyses, the grain size distribution in the superficial deposit in the Dubračina river basin affects sliding, creeping, excessive erosion and gully erosion processes. The distance from the dispersive sample affects the sliding, excessive erosion and gully erosion processes, and the factor map of the terrain surface dispersiveness affects the sliding and gully erosion processes. Research has shown that, in the Dubračina river basin, the three most important factors that affect the zoning of the susceptibility to sliding are lithology, land cover and mean annual precipitation, and those that affect the zoning of the susceptibility to creeping are lithology, distance from the road and slope. The three factors that affect susceptibility to excessive erosion the most are distance from the dispersive sample, lithology and land cover, whereas for the gully erosion process the three most important factors are lithology, land cover and aspect. The most important factors that affect the zoning of the susceptibility to rockfall are slope, lithology and land cover. The validation of susceptibility maps, which were produced for each process using two bivariate methods, allows for the conclusion that for the sliding, creeping and gully erosion processes the IVM method, without the application of the grain size distribution factor maps, is more precise than the FRM method. As regards the susceptibility to excessive erosion, the FRM method, without the application of grain size distribution maps, yields better forecasting results than the IVM method. When it comes to the rockfall process, the FRM-derived susceptibility map is better than the IVM-derived map. This research was carried out in the overthrust zone of carbonate over flysch which allows for the presumption that such superficial geodynamic (engineering-geological) processes also take place in other similar areas which could, therefore, also be the subjectmatter of susceptibility zoning research. However, occurrences of dispersive clays and excessive erosion in other overthrust zones of carbonate over flysch along the Adriatic coast are unlikely, except in the basins of the Bakarački rov and Ričina creeks which belong to the Vinodol valley together with the Dubračina river basin.