The lengths of the Slovenian caves follow the power-law distribution through several orders of magnitude, which implies that the caves can be considered as natural fractal objects. Fractal dimensions ...obtained from distribution of all caves are about 1.07, and vary within different tectonic and hydrogeological units. Some deviations from the ideal best fit line in log-log plots (i.e. lower and upper cut-off limits) can be explained by underestimation, as many very short caves are not registered. The study of tectonic and hydrogeological setting indicates that the greatest dimensions occur in the rocks with karstic-fracture and fracture porosity and the lowest in low-permeability rocks. Proximity to major tectonic structures shows a detectable effect on the cave length distribution, and the influence is greatest for the caves closer to the faults and thrust fronts. Dimensions are lower than those of fracture networks and faults, which can be most probably explained by flow channeling along the fracture networks, which causes the decrease of fractal dimension. The physical causes of power law scaling and variations in fractal dimensions (power law exponents) are still poorly understood, but the behaviour of fracture networks is believed to be caused by a scale-independent fractal fragmentation of the blocks, and during the process of forming the caves inherit some fractal geometrical properties of the networks.
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.
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IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UL, UM, UPUK
Sulphide springs in Slovenia are very rare and they form a peculiar feature in a carbonate setting. The basic geological, hydrogeochemical and isotopic characteristics of the veplenica sulphide ...dolomite spring (Trebusa Valley, NW Slovenia) were investigated, along with the geochemical and mineralogical characteristics of the sediment deposited at the spring location. Geological mapping defined a small, structurally and lithologically isolated dolomitic aquifer. The major groundwater geochemical composition is HCO3 ^sup -^ > Mg^sup 2+^ > Ca^sup 2+^, indicating dissolution of dolomite. The concentration of SO^sub 4^ ^sup 2-^ was very low. The groundwater was generally close to saturation with respect to calcite and dolomite. Geochemical modelling and other analyses indicated sulphur to originate not from gypsum and/or anhydrite, but from some other sources. We suggest the origin of sulphur be the dissolution of volcanogenic sulphidic enrichment in a highly variable, Ladinian clastic-limestone-volcanic rock association, forming the basis of early Carnian Cordevolian dolomite, from which the spring discharges. The measured δ^sup 13^C^sub DIC^ value of -11.9 per thousand indicates groundwater with a contribution of degraded organic matter and dissolved inorganic carbon in the aquifer. The isotopic composition of oxygen (δ^sup 18^O^sub H2O^), hydrogen (δD^sub H2O^) and tritium was -8.1 per thousand, δD -51.4 per thousand and ^sup 3^H 3.64 TU, respectively. The δ^sup 18^O and δD values indicated recharge from precipitation with H2S exsolution, while the ^sup 3^H activity shows groundwater older than 40 years. Mineralogical and geochemical analysis of sediment showed a typical carbonate (mostly dolomite) composition, which was in agreement with the geochemical and isotopic composition of the groundwater of the spring, indicating a deep sourced inorganic form of sulphur such as pyrite.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Hydraulic conductivities and specific storage coefficients of fractures and matrix in Slovenian carbonate aquifers were determined by Barker’s method for pumping test analysis, based on fractional ...flow dimension. Values are presented for limestones and mainly for dolomites, and additionally for separate aquifers, divided by age andlithology in several groups. Data was obtained from hydrogeological reports for 397 water wells, and among these, 79 pumping tests were reinterpreted. Hydraulic conductivities of fractures are higher than the hydraulic conductivities of matrix, and the differences are highly statistically significant. Likewise, differences are significant for specific storage, and the values of these coefficients are higher in the matrix. Values of all coefficients vary in separate aquifers, and the differences can be explained by diagenetic effects, crystal size, degree of fracturing, andcarbonate purity. Comparison of the methods, used in the reports, and the Barker’s method (being more suitable for karstic and fractured aquifers), shows that the latter fits real data better.
The porous structure of a material is an important mechanical property that affects the hardness of materials. We cannot apply Euclidian geometry to describe the porosity of hardened specimens ...because porosity is very complex. Here we use fractal geometry to describe the porosity of robot laser-hardened specimens, hi this paper, we describe how the parameters (speed and temperature) of the robot laser cell affect porous metal materials using a new method, fractal geometry. We describe a new technological process of hardening, which can decrease the porosity of hardened specimens. The new process uses robot laser hardening with an overlapping laser beam. First, we hardened specimens using different velocities and temperatures and then repeated the process, hi addition, we present how the speed and temperature affect the porosity in two different processes of robot laser hardening. Furthermore, we present the improved results after hardening with the overlap process. To analyse the results, we used one method of intelligent system, neural networks and a relationship was obtained by using a four-layer neural network. We compare both processes.
Slovenia’s carbonates represent an ideal research polygon for the karst and fractured aquifers,
as the limestone and dolomite sedimentation persisted almost continuously from the Upper
Permian to the ...end of the Mesozoic. This process resulted in deposition of carbonate rocks
which are several kilometers thick. A database of 430 boreholes in dolomite and limestone
aquifers has been constructed, out of which 90 boreholes used for public water supply systems,
were chosen for hydrogeochemical and isotopic analyses. Results indicate several differences
between individual dolomite and limestone aquifers for most of analyzed geochemical
parameters. Total alkalinity ranges from 2.1 mM to 8.6 mM. The study is focused on calcium
and magnesium concentrations within aquifer and revealed, that the average value for Ca2+ in
all aquifers is 63.8 mg/l (ranging from 22.7 to 313 mg/l), while for Mg2+ is 30.8 mg/l (ranging
from 6.7-72.0 mg/l). Mg2+/Ca2+ molar ratios lie mostly in the range 0.20 to 1.84, indicating
weathering of pure dolomites; however large value spans occur for different aquifers, which can
be explained by the composition and origin of dolomite rocks. The highest values of Mg2+/Ca2+
ratio appear for late-diagenetic Cordevolian dolomites, while the lowest for relatively impure
Lower Triassic dolomites. δ13CDIC range from −14.6 to −8.2‰ and reveal the contribution of
organic matter and dissolution of carbonates within aquifer. According to mass balance calculation it was estimated that contribution of organic matter within aquifer ranged from 41.0 to
62.2% and dissolution of carbonates from 37.8 to 59.0‰.
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