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An eleven-year monitoring (1987/88–1999) of chemical composition of Na-HCO3 thermal water from the wells Sob-1 and Sob-2 has shown long- and short-time scale changes occurring as a result of mixed character of abstracted thermal water and overexploitation of the wells. Constantly reoccurring changes of dynamic pressure induced the inflow of variable proportions of water from the most productive aquifer Thermal I and from lower-permeability aquifers in the underlying Lendava Formation which contain abundant CO2. The chloride ions originate from formation waters in the Lendava Formation, and for Thermal I, a local natural background is 80–85 mg/L. The fluoride ions mainly originate from waters in the Lendava Formation but do not correlate entirely with the chloride ions. It is assumed their abundance is largely controlled by interaction of CO2-rich waters with detritial marine carbonates and clay minerals. Temporal variations of concentrations of the bromide and iodide ions in thermal water from the Sob-1 largely correlate with variation of the chloride ions and indicate that the Lendava Formation is their major source. By overexploitation, some low-permeability aquifers in the Lendava Formation have been activated along with leakage from clayey lenses rich in organic matter and coal in the Mura Formation. The sources rich in the bromide and iodide, and iodide and chloride ions have been also recognized in the Sob-2 well at high pumping rate that amounted to 8.7 L/sec.

Chlorite, ordered mixed-layer chlorite-smectites, laumontite, quartz and albite are the most widespread alteration assemblage in cone-building and near-vent successions of lavas, autoclastic, pyroclastic and resedimented volcaniclastic deposits of the Oligocene Smrekovec Volcanic Complex, Slovenia. Randomly interstratified corrensite-chlorite with ~ 70–80% of corrensite layers (R0 Cr-Ch) is less common in occurrence and associated either with clinoptilolite and heulandite in fine-grained vitric tuffs, or with prehnite, laumontite, actinolite, analcime and albite in extensively altered and/or fractured host-rocks. The assemblage with clinoptilolite and heulandite indicates the temperatures of formation of

Hydrothermal zeolites (laumontite, yugawaralite, analcime, heulandite, clinoptilolite), prehnite and pumpellyite have been recognised in a succession of volcanic, autoclastic, pyroclastic, resedimented volcaniclastic and mixed siliciclastic–volcaniclastic deposits. In cone-building lithofacies association attaining 310 m, the alteration minerals commonly change within a single normally graded depositional unit or alternate in the section on a dm- to m-scale, according to the host-rock lithofacies. Fine-grained deposits rich in juvenile glassy pyroclasts are altered to heulandite and clinoptilolite or analcime, and laumontite widely occurs in coarse-grained host-rocks (lapilli tuff, hyaloclastite breccia, volcaniclastic breccia, hyaloclastites) and fracture systems. In near-vent lithofacies association attaining 420 m, prehnite–laumontite, laumontite–analcime, and laumontite–heulandite–clinoptilolite zones developed as a result of superimposed thermal regime generated by the emplacement of an over 200 m thick sill. The recognised dependence of alteration on porosity, permeability and fracturing of the host-rock is closely related to hydrological conditions in the stratovolcano-hosted hydrothermal system with convective–advective flow regime. After separation of steam and gases from convecting hydrothermal fluids, denser liquids outflowed intermittently, preferentially through steeply inclined (20–30°) high-permeability layers in the stratovolcano edifice. In low-permeability layers the flow was slow and thermal conditions were mainly attained by conduction. Zeolites developed only in coarse- and fine-grained vitroclastic tuffs, presumably by the dissolution of volcanic glass. The interstratified siliciclastic siltstones, tuffites and resedimented deposits with low content of glassy particles are devoid of zeolites and indicate compositional constraint on zeolitisation. Lava flows, cooling in a submarine environment and undergoing disintegration and mingling with the enclosing water-saturated sediment were individual, ephemeral and spatially localised high-temperature hydrothermal systems favourable for the formation of pumpellyite, prehnite and laumontite.

Sedimentary and stratigraphic developments with tectonic settings of Paleogene and Neogene sediments in individual Central Europe basins.

The Upper Oligocene Smrekovec Volcanic Complex (SVC) represents the remains of a submarine stratovolcano which underwent Early Miocene tectonic dissection and large-scale displacement along the Periadriatic Line. According to the lithofacies architecture, abundance and spatial distribution, central, medial and distal zones of the former volcano edifice have been recognized. The zones extend at a distance of 0–2 km, 2–5 km and 5–20 km south of the Periadriatic Line, respectively. Lavas, shallow intrusive bodies, autobreccia, peperite and hyaloclastite deposits occur mainly in the central zone, which is extensively altered under hydrothermal conditions, characterised by the development of zeolites (mainly laumontite), prehnite, chlorite, albite and epidote. Explosive volcanic activity intensified with the evolution of magma from basaltic andesitic to dacitic. Gas- and water-supported eruption-fed density flows are assumed. Their deposits show lithofacies organisation in pyroclastic depositional units (PDUs) similar to either volcaniclastic turbidites (Type 1) or thin subaqueous ignimbrites (Type 2). Volcaniclastic debris flow deposits are developed as volcaniclastic breccia and sandy debris flow deposits; the former occurs in the central and medial zones, and the latter occurs in the medial zone only. The most widespread lithofacies in the SVC are volcaniclastic turbidite deposits. Three types of sedimentary unit (TSU) have been distinguished. Type 1 is 2–5 m thick and dominated by the massive division. It mainly occurs in the central zone. Type 2 is 0.7–3.5 m thick and occurs in the central and medial zones. It comprises the massive division, bedded fining- and thinning-upward division, and a horizontally, wavy and cross-laminated division, topped by massive fine-grained tuff. Type 3 is 0.1–1.5 m thick and mainly occurs in the distal zone. The massive division is absent, and thinly-bedded and laminated divisions are topped by massive fine-grained tuff. Volcaniclastic turbidites were settled from low-density turbidity currents and related suspension clouds. Mixed volcaniclastic–siliciclastic deposits are subordinate in occurrence and restricted to the distal zone. They are commonly reworked by bottom currents.

Middle to Upper Pliocene (~ 3 Ma) Grad Volcanic Field (SW Pannonian basin system) encompasses an area of about 3 km2, of which some 1.7 km2 belong to the outcropping volcanics. Pyroclastic and syn-eruptively reworked volcaniclastic deposits are the most widespread in occurrence. Remains of an autobrecciated lava flow, a residual neck and their peperites are partially reworked by a large debris flow. Volcanic activity occurred in a continental depositional environment dominated by alluvial fan and braided river systems. Streams draining from the north-west to the south-east were infilling a rapidly subsiding Radgona Depression. The style of volcanic activity was mainly explosive and was reinforced by hydrovolcanic processes. Three volcanic centres probably existed, and they migrated spatially and temporally from the north to the south over a distance of some 5.6 km. The rocks of the northernmost volcanic centre are fairly eroded and contain abundant, up to 10 cm sized lherzolite xenoliths. The largest crater developed about 2.5 km to the south. From an early maar stage, a tuff-cone, and subsequently, a tuff-ring evolved. The crater was filled with eroded pyroclastic material and stream load. A new vent became active some 500 m to the south. Initial stage was mainly magmatic and produced pyroclastic flow and fall deposits. Late-stage eruptions were predominantly hydrovolcanic (phreatomagmatic and phreatic), and built up a small tuff-cone having some 300 m in diameter. Trachybasaltic and subordinate basanitic magmas erupting in the Grad Volcanic Field are geochemically distinguishable from the neighbouring occurrences in the South Styrian Basin and the South Burgenland Swell. Relatively lower abundance of TiO2, MgO, Sc, V and Cu, and higher abundance of MnO, P2O5, Zn, Sr, Zr, Hf, Nb, Ba, Ta and U indicate somewhat different source and/or evolutionary pattern.

Grain-size analysis, mineral composition of heavy and light fraction, and surface texture of quartz grains in soilsdeveloped on different parent carbonate rocks in the region of the West Karavanke Mountains and the high plateausof the Julian Alps (Mežakla, Pokljuka, Jelovica) revealed their polygenetic origin. Homogeneity of the heavymineral assemblage in the soils developed on different parent carbonate rocks indicates – besides autochthonousmaterial (insoluble residue of carbonate rocks), the presence of allochthonous (external) material in the compositionof mineral component of soils, too. Heavy mineral assemblage indicates a metamorphic-igneous source area, whichis most probably in the Central Alps. The Drava glacier transported material from there, and deposited it in tillesalong the Drava valley. They were exposed to the fluvial and eolian erosion after the Würm deglaciation. Mostly siltymaterial was transported over the ridges of the Karavanke Mountains by the northeren winds. Their deposition beganon the southern calm and protected slopes and saddles, and continued southward on high plateaus of the JulianAlps, and very possibly even farther.

Importance of boron compounds in wood preservation is increasing due to their low environmental impact, high efficacy and the fact that many other active ingredients have been removed from the market after the introduction of the Biocidal Products Directive. The most important drawback of boron is prominent leaching in wet environment. In order to improve their fixation, and performance against wood decay fungi, boric acid was combined with montan wax emulsion. Possible synergistic effects of boric acid and montan wax were determined according to modified EN 113 procedure. Norway spruce and beech wood specimens were exposed to three white rot (Trametes versicolor, Pleurotus ostreatus and Hypoxylon fragiforme) and brown rot wood decay fungi (Gloeophyllum trabeum, Antrodia vaillantii and Serpula lacrymans) for 12 weeks. Boron leaching from vacuum/pressure treated Norway spruce wood was determined according to the continuous (EN 84 and ENV 1250-2) and non-continuous (OECD and prCEN/TS 15119-1) procedures. Boron was determined with ICP mass spectrometry in collected leachates. The results of the fungicidal tests clearly showed that montan wax emulsion and boric acid act synergistically against tested wood decay fungi. Approximately 50% lower boric acid retentions are required in combination with montan wax emulsions to achieve sufficient protection against wood rotting fungi. However, it is even more important that all leaching tests performed proved that the addition of montan wax decreased boron leaching from impregnated specimens for 20% up to 50%.

Thermal water produced from the Sob-1 well is a water mixture contributed from several stratified aquifers that belong to two hydrogeological subsystems termed Middle- and Upper Subsystem. The subsystems’ thermal waters differ appreciably in the REE and Y signatures; ΣREE + Y averages to about 10 and 0.2 ppb for the Middle- and Upper-subsystem, respectively. As the Sob-1 well experiences pressure cycling, the inflow from the subsystems’ aquifers is not constant but cycles as well causing the cycling of chemical composition of abstracted thermal water mixture, including REEs and Y. PAAS normalized cycling REE and Y distribution for thermal water mixture from the Sob-1 well indicates that the abundance of REEs and Y is mainly controlled by solubility of their carbonate and bicarbonate species, and therefore by availability of free and dissolved carbon dioxide in the aquifer.

Deep welling in the Benedikt area has proven the existence of recently active hydrothermal system in pre-Tertiary basement composed of banded gneiss, marble and schist originating from a regionally metamorphosed sequence of clastic sediments. Two aquifers with very high fracture porosity were tapped—at depths between 1,485–1,530 and 1,848–1,857 m, where the welling stopped owing to a technical failure. The water temperature exceeds 90°C, while the yield of 100 l/s is limited only by the well performances. The Na-HCO3 dominated water is classified as a CO2-rich healing mineral water suitable for drinking, bottling and balneology. The free degassing gas is almost pure CO2 (99.9 %) and its δ13C composition indicates volcanic origin. The tapped water is relatively old, probably of Pleistocene age at least, and the planned exploitation must consider reinjection in order to protect this valuable natural resource from overexploitation. This recent hydrothermal system is characterised by dominating vertical circulation of waters and is superimposed on older, already inactive hydrothermal system(s), recognised by veins of either metal sulphides and quartz, or calcite. These vein minerals precipitated from hydrothermal fluids migrating from a deeper source towards the ancient surface through a fracture system, which is now self-sealed already. The distribution of metal sulphides indicates that the source might have been a deep-seated Neogene pluton genetically related to the tonalites and quartz diorites that outcrop in the Pohorje Mountains, or a subvolcanic-level volcanic body related to the Neogene volcanic activity in the Graz Basin.

Volcanic rocks occurring in Ladinian (?) marls, interstratified with limestone (Solčava beds), at Grohat Alpine Meadow and Lipni plaz, Mt. Raduha, are shallow intrusives bodies with porphyric structure, and basaltic andesitic, acid andesitic and dacitic composition.Abundance of major oxides and trace elements in the studied rocks is similar to those observed in the Tertiary Smrekovec volcanic rocks suggesting contemporaneous formation and close genetic relationship.

The Mura basin in north-eastern Slovenia is made up of two depressions, developed during the Late Neogene and Early Pliocene all within a widespread system of Pannonian basins. Both depressions are characterized by the occurrence of thermal waters of somewhat different hydrogeochemical character. Radgona depression is in the northern part of the basin and reaches depths of about 2 km. Thermal waters are generally dominated by sodium-bicarbonate, not related to the age of an aquifer, its wallrock composition, the type of porosity or total concentration of dissolved solids. Locally, sulphate-rich waters are encountered, and they are related to the presence of gypsum in the rocks of pre-Tertiary basement. The adjacent Ljutomer depression is over 4 km deep and comprises compartments with stagnant or semi-stagnant aquifers. Herein saline waters predominate, even in the aquifers of carbonate composition and abundant CO2 gas. In shallower, unconsolidated, intergranular aquifers sodium-bicarbonate waters predominate. Thermal aquifers of this type are very important to the economy of the region, but they are also subjected to overexploitation which is reflected in time-dependent changes of dynamic pressures, temperature, conductance, salinity, pH and concentration of major ions, trace elements, dissolved gasses, and total organic carbon. Mineral waters occur in shallow aquifers or springs in marginal areas of the Radgona depression. Bicarbonate waters are dominated by calcium, or both calcium and sodium. Some mineral waters are formed mainly by penetration of CO2 gas into shallow aquifers and consequent water–rock interaction. Composition of some mineral waters indicate their possible evolution from thermal waters which have risen from central parts of the Radgona depression along deep-seated faults, and have been modified by cooling and mixing processes.

Prvi slovar slovenske geoloske terminologije je nastajal pet desetletij in je delo vec generacij strokovnjakov s podrocja geologije. V njem so zajeti geoloski strokovni izrazi, ki so bili izpisani iz slovenske strokovne literature, slovar pa skusa zajeti tudi novejse strokovno izrazje, ki izvira predvsem iz angleske literature. Slovar obsega 10.811 enobesednih ali vecbesednih geoloskih izrazov in v vecji ali manjsi meri zajema vsa glavna podrocja geoloske vede: mineralogijo, kristalografijo, petrologijo, sedimentologijo, paleontologijo, paleoekologijo, stratigrafijo, geologijo kvartarja, fizikalno geologijo, geofiziko, seizmologijo, inženirsko geologijo, hidrogeologijo, geokemijo, nahajalisca mineralnih surovin in regionalno geologijo. Soizdajatelj: Oddelek za geologijo Naravoslovno-tehniske fakultete UL

Low-temperature thermal waters (