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1.
The largest karst cave discovered in a tunnel during motorway construction in Slovenia’s Classical Karst (Kras) 总被引：1，自引：0，他引：1
Karst researchers of the Karst Research Institute ZRC SAZU are regularly consulted during the planning of Slovenia’s motorways
and invited to observe and monitor construction in the karst areas. More than 350 caves have been discovered in the course
of building 60 km of new motorways over the past decade. Access to the most important caves is preserved by concrete tubes
closed with metal covers at the roadside. The largest cave system in a tunnel, named LC-S647, is almost entirely preserved.
The protection of this cave will serve as a good example for the preservation of natural heritage in the future. Construction
work for the motorway uncovered a high degree of karstification. In particular, the discovery of this cave in the Kastelec
tunnel LC-S647 showed the existence of a major cave system in the geological and speleological past. A number of unconnected
passages have also been found. Caves discovered during highway construction have brought new knowledge about the cavernosity
and the geological history of this part of the karst. 相似文献
2.
Three discriminant function models are raised and cross-compared in order to distinguish geochemical patterns characteristic
for the Drava River floodplain sediments. Based on data representing total element concentrations in samples collected from
alluvium (A), terrace (T), and unconsolidated bedrock (B) at the border of a floodplain, four element clusters emerged accounting
for discrimination between the referred groups of sediments. The most prominent is contaminant/carbonate cluster characteristic
for alluvium. The other two are: silicate cluster typical for unconsolidated geological substrate (Neogene sedimentary rocks);
and naturally dispersed heavy metal cluster separating terrace from the former two groups. Models introducing depth intervals
and single profiles as grouping criteria reveal identical sediment-heavy metal matrices. The second important issue of this
paper is possibility of reclassification of samples originally assigned to one of the a priori defined groups of sediments,
based on established geochemical pattern. The mapped geological units can be reconsidered by the post hoc assignments to a
different group if geological border between alluvium and terrace or between terrace and bedrock can not be established geologically
with absolute certainty. 相似文献
3.
The hydraulic behaviour of the karst aquifer in the Hubelj spring catchment area (SW Slovenia) was studied by using an indirect
research method based on natural tracers. The variations of natural tracers (in precipitation and in groundwater) during the
storm event made possible the separation of the Hubelj spring storm hydrograph by the three-component separation technique.
The results produced information on the aquifer recharge, storage and discharge processes, as well as on the mechanisms that
affected them. They verified the so-called epikarst hypothesis presuming that an important part of a karst aquifer recharge
reaches rapidly and intensively from the epikarst zone. It was demonstrated that epikarst water could occupy up to 50% of
the spring discharge during precipitation events. This phenomenon could have important consequences on protection and management
of the problems of karst aquifers, including engineering problems in karst areas. With this respect the results could give
way to new engineering ideas. 相似文献
4.
Mihael Brencic 《Environmental Geology》2006,49(6):804-813
During the planning, designing, construction, operation and maintenance of highways, groundwater can be of important environmental
and constructional constraint that can significantly influence the safety operation of traffic and of big influence on the
operational costs of highways. To classify and conceptualize the relation between groundwater and highways, three important
groups of problems can be determined: groundwater protection from highway influences, protection of highway from groundwater
and economic use of groundwater for highway operation. In the present study, groundwater management strategies are represented
during all life cycles of highways. Greater emphasis is given to groundwater protection and field hydrogeological investigations
for proper groundwater management related to the highway. The approach adopted in Slovenia and the role of hydrogeology is
given as an illustration. 相似文献
5.
The preparation of the preliminary seismic hazard maps of the territory of Slovenia has been based on an expansion of the basic approach laid out by Cornell in 1968. Three seismic source models were prepared. Two of them are based mainly on the earthquake catalogue using the Poissonian probability model. A map of seismic energy release and a map of earthquake epicenter density are used to delineate seismic sources in these models. The geometry of the third model which is based on a rough estimate of seismotectonic setting is taken from the probabilistic seismic hazard analysis of a nuclear power plant in Slovenia. Published ground motion attenuation models based on strong motion records of recent strong earthquakes in Italy are used. Test maps for variable and uniform b-values are presented. The computer program, Seisrisk III, developed by the U.S. Geological Survey is used. 相似文献
6.
Branka Trček 《Environmental Geology》2007,51(5):761-765
The role of an epikarst zone in the karst aquifer hydraulic behaviour was brought into focus in our studies referring to the
catchment area of the Hubelj spring (SW Slovenia). This study points out the significance of effects of the fast preferential
flow—epiflow, which is the main factor controlling solute/contaminant transport towards the aquifer saturated zone. The so-called
epikarstic hypothesis is verified on the basis of the most significant research results that are supported by the most important
findings from the literature. 相似文献
7.
The world-class Idrija mercury deposit (western Slovenia) is hosted by highly deformed Permocarboniferous to Middle Triassic sedimentary rocks within a complex tectonic structure at the transition between the External Dinarides and the Southern Alps. Concordant and discordant mineralization formed concomitant with Middle Triassic bimodal volcanism in an aborted rift. A multiple isotopic (C, O, S) investigation of host rocks and ore minerals was performed to put constraints on the source and composition of the fluid, and the hydrothermal alteration. The distributions of the 13C and 18O values of host and gangue carbonates are indicative of a fracture-controlled hydrothermal system, with locally high fluid-rock ratios. Quantitative modeling of the 13C and 18O covariation for host carbonates during temperature dependent fluid-rock interaction, and concomitant precipitation of void-filling dolomites points to a slightly acidic hydrothermal fluid (13C–4 and 18O+10), which most likely evolved during isotopic exchange with carbonates under low fluid/rock ratios. The 34S values of hydrothermal and sedimentary sulfur minerals were used to re-evaluate the previously proposed magmatic and evaporitic sulfur sources for the mineralization, and to assess the importance of other possible sulfur sources such as the contemporaneous seawater sulfate, sedimentary pyrite, and organic sulfur compounds. The 34S values of the sulfides show a large variation at deposit down to hand-specimen scale. They range for cinnabar and pyrite from –19.1 to +22.8, and from –22.4 to +59.6, respectively, suggesting mixing of sulfur from different sources. The peak of 34S values of cinnabar and pyrite close to 0 is compatible with ore sulfur derived dominantly from a magmatic fluid and/or from hydrothermal leaching of basement rocks. The similar stratigraphic trends of the 34S values of both cinnabar and pyrite suggest a minor contribution of sedimentary sulfur (pyrite and organic sulfur) to the ore formation. Some of the positive 34S values are probably derived from thermochemical reduction of evaporitic and contemporaneous seawater sulfates.Editorial handling: P. Lattanzi 相似文献
8.
Medium-temperature thermal waters in the Mura basin occur in hydrogeological systems different in age, burial depth, temperature, porosity and permeability, and the presence of free carbon dioxide which penetrates through the fractures from pre-Tertiary basement. The waters commonly belong to sodium-bicarbonate hydrogeochemical facies, but may have significantly different amounts of total dissolved solids, including trace elements. Thermal waters occurring in low-permeable, well-compacted and moderately fractured Tertiary sediments older than Upper Pliocene are the richest in trace elements, although their abundance may be very variable from one aquifer to another. The ratios of major alkaline and alkaline earth elements (Na, K, Ca) and trace elements (Li, Rb, Cs, Ba, Sr) commonly show relative enrichment in highly mineralised waters with respect to the waters with lower mineralisation. Rare earth elements (REEs) and Y show only minor fractionation in the highly mineralised waters, whereas in the waters with lower mineralisation strong fractionation of heavy rare earth elements (HREEs) over light rare earth elements (LREEs) occurs, along with a pronounced positive europium anomaly. Positive Th/U ratios are commonly observed, although both actinide elements occur in the range of some hundredths of ppb to some ppb. Trace elements were particularly useful in the study of well cycling in two hydraulically interconnected geothermal wells in the town of Murska Sobota, which produce a mixture of low- and high-mineralised waters. 相似文献
9.
Marbles from the Pohorje area in Slovenia are investigated by mineralogical-petrographical analyses of thin sections as well as by cathodoluminescence in order to detect their local variability in texture and mineral assemblages. The CL colours observed in a cold cathode device are related to the manganese contents. An attempt is made to relate the textures seen under CL to mineral reactions during the process of metamorphism. The predominantly calcite marbles from Pohorje exhibit orange luminescence with some dolomite lenses with red luminescence. The typical mineral assemblages are calcite+tremolite+phlogopite or calcite+dolomite+tremolite+phlogopite. Therefore, the estimated temperature from the stability of mineral assemblage is assumed at approximately 500 °C. 相似文献
10.
《水文科学杂志》2013,58(2):314-324
Abstract An approach to the global estimation of water balance elements and their spatial distribution using GIS is presented. It is primarily related to the catchments where measured data are scarce and the spatial differentiation of the hydrological characteristics is not possible without climatological data. Emphasis is placed on estimating the water balance of transboundary karstic aquifers, where problems concerning the hydrometeorological data, catchment boundaries and determination of water balance elements in general are far more complex. The runoff estimation was done using the Turc and Langbein methods, which are the most frequently applied in this region. The years 1961–1990 were used as the reference period. Based on comparison of the results, the applicability of the methods is discussed. The approach proposed is suitable for estimation of water balance in the study area and may also be applied in a wider region. 相似文献