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1732. Tectonics and gravitational phenomena, part two : the Trnovski gozd-Banjšice-Šentviška Gora degraded plainLadislav Placer, Tomislav Popit, Igor Rižnar, 2024, original scientific article Abstract: The article describes the recent conditions at the Paleogene thrust contact between the External Dinaric Thrust Belt composed of carbonate rocks and the External Dinaric Imbricate Belt composed of flysch rocks, geographically, between the Trnovski gozd (Trnovski gozd plateau) and the Vipava Valley at the northwestern end of the Dinarides. Fossil and recent gravity-related phenomena that indicate the uplift of the southwestern edge of the External Dinaric Thrust Belt and the larger complex in the hinterland are found there. However, these phenomena are not related to the reactivated Paleogene thrust tectonics, but to the Neogene-recent underthrusting as a consequence of the Microadria (Adriatic Microplate) movement towards the Dinarides. Only arguments for these processes are presented in this article.
Keywords: External Dinarides NW, geomorphology, gravitational phenomena, karst plains, degraded karst plains, Idrija fault
Published in DiRROS: 09.07.2024; Views: 402; Downloads: 178
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1733. Isotopic composition of carbon (▫$\delta$▫13C) and nitrogen (▫$\delta$▫15N) of petrologically different tertiary lignites and coalsTjaša Kanduč, Miloš Markič, 2024, original scientific article Abstract: This study investigates the carbon (δ13Corg) and nitrogen (δ15N) isotopic composition of tertiary lignites and coals from six sedimentary basins: Velenje, Mura-Zala, and Zasavje in Slovenia; Sokolov in Czech Republic, Barito in Indonesia; and Istria in Croatia. The aim is to investigate the correlation between the fine detrital (fD) component and δ13C and δ15N in Velenje lignite samples. Additionally, we aim to evaluate the biogeochemical processes of organic substances during their deposition in all analyzed samples, calculate their δ13CCO2 values and compare the analyzed values of δ13C and δ15N to those reported in the literature. Thirty-two samples were analyzed, predominantly from the Velenje ortho-lignite (Pliocene), with additional lignites and coals from the Pannonian to Paleocene epochs for comparison. Carbon isotopic composition (δ13Corg) ranged from -27.9 to -23.6 ‰, and nitrogen isotopic composition (δ15N) ranged from 1.8 to 7.4 ‰. The fine-detrital lithotypes of the Velenje ortho-lignite exhibited the most negative δ13Corg values due to anaerobic bacterial activity in an intramontane alkaline lake environment influenced by the carbonate hinterland. Moreover, gelification processes affected fine-detrital organic matter more than larger wooden pieces. Terbegovci, Hrastnik meta-lignites, and Barito sub-bituminous coal also displayed low δ13Corg values, indicating limited gelification, while variations in the δ15N values suggested differences in mineralization. The Velenje xylitic lithotypes have higher δ15N values, indicating a more intense mineralization under aerobic conditions. Raša ortho-bituminous coal, deposited in a brackish environment, displayed the highest δ13Corg values and a wide range of δ15N values due to fluctuating water tables in a paralic carbonate platform environment. The lowest δ15N value was observed in the Sokolov Basin lignite coal, indicating minimal mineralization and low bacterial activity. The isotopic composition of CO2 in air (δ13Cair), which was calculated using the δ13C values in lignites and coal, ranged from -8.4 to -3.4 ‰, with Velenje lignite displaying the minimum value and Raša coal showing the maximum value. The determined δ13C and δ15N values of the coal and lignite samples in this research fall within the typical range of world coals.
Keywords: lignite, coal, petrography, C and N isotopic composition, gelification, mineralization
Published in DiRROS: 09.07.2024; Views: 383; Downloads: 150
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1734. Middle Triassic deeper-marine volcano-sedimentary successions in western SloveniaDragomir Skaberne, Jože Čar, Maja Pristavec, Boštjan Rožič, Luka Gale, 2024, original scientific article Abstract: A Ladinian – Carnian volcano-sedimentary succession from western Slovenia, paleogeographically belonging to the western Slovenian Basin, is presented in 17 sections. Except for the lowermost part, which is dominated by volcanics and volcaniclastics, most of the succession is dominated by shale, sandstone, and micritic limestone. Various authors use the name Pseudozilja and/or Amphiclina formation for this part, which is dominated by clastics, but they disagree on the differences between the formations. The lower Pseudozilja formation, represented by the Malenski Vrh section, comprises diabase, tuf and shale. No substantial differences in lithological composition have been observed between the upper Pseudoziljaformation and the Amphiclina formation, which are predominantly composed of shale, sandstone, and limestone. The shale and sandstone are largely composed of quartz, feldspar, and lithic grains (especially volcanics), which vary in proportions. Limestone varieties comprise hemipelagic limestones and resedimented carbonates deposited by gravity-flows. Deposition of the Ladinian – Carnian volcano-sedimentary succession took place on or near the continental slope that was generally inclined to the S, with the direction of transport mainly from N to S.
Keywords: stratigraphy, carbonate-siliciclastic deposits, Slovenian Basin, Middle Triassic, Ladinian, Carnian, Pseudozilja formation, Amphiclina formation
Published in DiRROS: 09.07.2024; Views: 360; Downloads: 150
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1735. Palaeoecological significance of the trace fossil Circulichnis Vyalov, 1971 from the Carboniferous of the Donets Basin, UkraineVitaly Dernov, 2024, original scientific article Abstract: The ichnogenus Circulichnis Vyalov is a horizontal a ring- or ellipse-shaped burrow and/or locomotion trace of an unknown producer, most likely an annelid or a “worm”, preserved on the bedding plane. This ichnogenus is known over a wide age interval (Ediacaran–Oligocene). Circulichnis demonstrates a wide ecological range and has been found in continental (Mermia ichnofacies), shelf, and relatively deep-water (turbidites) deposits. It is commonly interpreted as a sediment feeding trace, but the peculiarities of its formation remain somewhat mysterious, as it is unclear how the tracemaker reached the sediment surface, as lateral branches of the ring-shaped traces are extremely rare and have only been observed by a few researchers. A rather large specimen of Circulichnis montanus Vyalov, 1971 with a preserved lateral branch was found in the Mospyne Formation (upper Bashkirian, Lower Pennsylvanian) of the Donets Basin. This discovery confirmed the assumption made by Alfred Uchman and Bruno Ratazzi regarding the peculiarities of formation of Circulichnis. According to these authors, a single ring-shaped Circulichnis indicates an attempt to forage at a specific level in the sediment, while the lateral branches of Circulichnis are part of a vertical shaft leading to another level within the sediment. The study of Circulichnis montanus from the Donets Basin has confirmed that at least variant C of the Circulichnis formation scheme proposed by Uchman and Ratazzi is correct, i.e. the lateral branch is a horizontal or subhorizontal part of a generally vertical shaft. However, it is important to note that the correctness of variants A and B of the Uchman and Ratazzi scheme cannot be excluded. To answer this question unequivocally, new finds of well-preserved Circulichnis are necessary.
Keywords: trace fossils, Circulichnis, Pennsylvanian, Ukraine
Published in DiRROS: 09.07.2024; Views: 337; Downloads: 176
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1736. Signs of crustal extension in Lower Jurassic carbonates from central SloveniaLuka Gale, Boštjan Rožič, 2024, original scientific article Abstract: The Lower Jurassic Podbukovje Formation represents a succession of shallow marine carbonate rocks deposited on the former Southern Tethyan Megaplatform and one of its successors, the Adriatic Carbonate Platform. Several outcrops of the Podbukovje Formation from central Slovenia (southern margin of the Ljubljana Moor) are presented, bearing possible evidence of Early Jurassic extensional tectonics. Peritidal facies of the lowermost, Hettangian – Sinemurian, part of the Podbukovje Formation locally interfingers with bodies of matrix supported pervasively dolomitized polymictic breccia, several metres to tens of metres thick and is locally cut by neptunian dykes some few decimetres to metres wide. The same or slightly younger part of the formation locally contains grabens/half-grabens metres to tens of metres deep and filled with poorly sorted pervasively dolomitized matrix supported polymictic breccia. Small miliolid foraminifera are present within the clasts and in the matrix. Finally, partly dolomitized blocky breccia tens of metres thick locally overlies the Pliensbachian – lowermost Toarcian limestone with lithiotid bivalves. Besides completely and partly dolomitized clasts, the breccia contains a variety of limestone clasts and preserves common radial ooids and some bioclasts within the partially dolomitized matrix.
The Hettangian-Sinemurian breccias and dykes are presumably related to the early, diffused rifting stage of the Penninic (Alpine Tethys) Ocean, whereas Toarcian breccias relate to the main, focused rifting stage. Together with evolving biota and changing paleo-oceanographic conditions, the extensional tectonics may have been an important factor behind the facies changes observed within the Podbukovje Formation
Keywords: carbonate platform, External Dinarides, Early Jurassic, Podbukovje Formation, neptunian dyke, breccia
Published in DiRROS: 09.07.2024; Views: 360; Downloads: 160
Full text (10,26 MB) |
1737. Hydrogeochemical and isotopic characterisation of the Učja Aquifer, NW SloveniaPetra Žvab Rožič, 2024, original scientific article Abstract: The groundwater characteristics of the Učja aquifer were investigated using geochemical and isotopic data. The water discharge and physico-chemical properties of the groundwater and the Učja River reflect the climate that is characteristic of the area. The mixed snow/rainfall regime is characteristic for the Učja Valley, with the highest discharges appearing during the spring snowmelt and autumn precipitation, and the lowest discharges in the winter and especially summer months. The temperature of the groundwater and the Učja River is lower in winter and higher in summer. The specific electrical conductivity values indicate a very permeable carbonate aquifer. Higher conductivity values were observed in spring and autumn at all sampling sites, which is related to snowy and rainy periods. The groundwater from the Učja aquifer indicates a uniform type of water (Ca-Mg-HCO3), w it h Ca2+, Mg2+ and HCO3– the most abundant ions. Differences in Ca2+ and Mg2+ concentrations and in the Mg2+/Ca2+molar ratio between sampling sites were observed. Those springs with lower Mg2+ and lower Mg2+/Ca2+ molar ratios indicate limestone recharge areas, and those springs with higher Mg2+ and molar ratios indicate interaction with the dolomite hinterland. The pH values confirm alkaline waters characteristic of carbonate aquifers. The hydrogen (δ2H) and oxygen (δ18O) isotope values suggest the main source of water is from precipitation from a complex mixing of maritime and continental air masses. An altitude isotopic effect is observed with minor δ18O and δ2H depletion at higher altitude sampling sites compared to those springs at lower altitudes. The altitude isotopic effect is most prominent in spring. The δ13CDIC values indicate the dissolution of carbonates and the degradation of organic matter.
Keywords: groundwater, hydrogeochemistry, isotopes, cross-border aquifer, Učja Valley
Published in DiRROS: 09.07.2024; Views: 335; Downloads: 176
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1738. Vsebnosti potencialno strupenih elementov v sedimentih in vodah reke Meže in njenih pritokov, ki odvodnjavajo odlagališča rudarskih odpadkovMateja Gosar, Špela Bavec, Miloš Miler, Martin Gaberšek, 2024, original scientific article Abstract: Predstavljeni so rezultati spremljanja vsebnosti potencialno strupenih elementov (PSE) v sedimentih (v letih 2013, 2017, 2020) in vodah (v letih 2017, 2020) reke Meže ter njenih pritokov, ki odvodnjavajo odlagališča rudarskih odpadkov. Skupno 13 vzorčnih mest je vzpostavljenih v vzorčni shemi, ki omogoča dolgoročno opazovanje vpliva odlagališč rudarskih odpadkov. V sedimentih so zaradi vplivov več kot 300-letnega delovanja rudarsko-predelovalne industrije močno povečane vsebnosti PSE, predvsem Pb, Zn, Cd, Mo in As, ki s časom precej nihajo. Razlike v vsebnostih na istih lokacijah v različnih letih so najbolj izrazite v pritokih reke Meže, ki drenirajo odlagališča rudarskih odpadkov. Na vsebnosti imajo pomemben vpliv hidrološki pogoji, saj so ob višjem vodostaju in višjem pretoku vsebnosti PSE večje. Vodna erozija odlagališč ima pomemben vpliv na dotok onesnaženega materiala v vodotoke. V nasprotju s pritoki, v zgornjem toku reke Meže nismo opazili večjega vpliva višjega vodostaja in pretoka na vsebnosti PSE v sedimentih. Dolvodno od Žerjava so nihanja vsebnosti med posameznimi leti oz. različnimi hidrološkimi pogoji tudi v Meži večja. Predstavljeni rezultati kažejo, da so v sedimentih reke Meže in njenih pritokov vsebnosti Pb, Zn, Cd, Mo in As zelo velike ter krepko presegajo zakonsko določeno kritično vrednost za tla. V površinski vodi so vsebnosti PSE lokalno povečane in se s časom bistveno ne spreminjajo. Glede na primerjavo z zakonodajnimi smernicami, so v obravnavanih vodah lokalno presežene koncentracije Pb, Cd in Zn. Ocenjujemo, da je dinamika obremenjenosti sedimentov reke Meže s PSE vzdolž krajev Črna na Koroškem, Žerjav in Mežica zelo kompleksna. Poleg odlagališč rudarskih odpadkov na vsebnosti PSE v sedimentih in vodah vplivajo tudi razpršeni viri v okolju, kot so onesnažena tla in poplavne ravnice ter njihova različna stopnja onesnaženosti, saj je okolje obremenjeno zaradi dolgoletnih rudarskih in talilniških dejavnosti. Dodaten okoljski vpliv ima morda tudi sedanja industrijska dejavnost v dolini reke Meže.
Keywords: rudarjenje, rudarski odpadki, odlagališča odpadkov, potencialno strupeni elementi, rečni sedimenti, monitoring, onesnaženje okolja
Published in DiRROS: 09.07.2024; Views: 396; Downloads: 176
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1739. Petrology dataset of Pliocene-Pleistocene sediments in northeastern SloveniaEva Mencin Gale, Polona Kralj, Mirka Trajanova, Luka Gale, Dragomir Skaberne, 2024, other scientific articles Abstract: This is a dataset of petrological analysis of Pliocene-Pleistocene f luvial sediments from 14 gravely samples from the Slovenj Gradec, Nazarje, Celje and Drava-Ptuj Basin (northeastern Slovenia), collected for clast lithological analysis. The petrological analysis includes description of 155 thin sections of metamorphic, volcanic, volcaniclastic, clastic and carbonate rocks. This dataset provides grounds for determining the provenance of these gravel deposits, revealing possible resedimentation processes, and serves as a tool for drainage network interpretation in the Pliocene-Pleistocene.
Keywords: petrografska analiza, litološka analiza klastov, provenienca klastov, pliocensko-pleistocenski sedimenti
Published in DiRROS: 09.07.2024; Views: 368; Downloads: 152
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1740. Exploring the safety of cannabidiol (CBD) : a comprehensive in vitro evaluation of the genotoxic and mutagenic potential of a CBD isolate and extract from Cannabis sativa LAlja Štern, Matjaž Novak, Katja Kološa, Jurij Trontelj, Sonja Žabkar, Tjaša Šentjurc, Metka Filipič, Bojana Žegura, 2024, original scientific article Abstract: Cannabidiol (CBD), a naturally occurring cyclic terpenoid found in Cannabis sativa L., is renowned for its diverse
pharmacological benefits. Marketed as a remedy for various health issues, CBD products are utilized by patients
as a supplementary therapy or post-treatment failure, as well as by healthy individuals seeking promised advantages. Despite its widespread use, information regarding potential adverse effects, especially genotoxic
properties, is limited. The present study is focused on the mutagenic and genotoxic activity of a CBD isolate
(99.4 % CBD content) and CBD-rich Cannabis sativa L extract (63.6 % CBD content) in vitro. Both CBD samples
were non-mutagenic, as determined by the AMES test (OECD 471) but exhibited cytotoxicity for HepG2 cells
(~IC50 (4 h) 26 µg/ml, ~IC50 (24 h) 6–8 µg/ml, MTT assay). Noncytotoxic concentrations induced upregulation of
genes encoding metabolic enzymes involved in CBD metabolism, and CBD oxidative as well as glucuronide
metabolites were found in cell culture media, demonstrating the ability of HepG2 cells to metabolize CBD. In this
study, the CBD samples were found non-genotoxic. No DNA damage was observed with the comet assay, and no
influence on genomic instability was observed with the cytokinesis block micronucleus and the γH2AX and p-H3
assays. Furthermore, no changes in the expression of genes involved in genotoxic stress response were detected in
the toxicogenomic analysis, after 4 and 24 h of exposure. Our comprehensive study contributes valuable insights
into CBD’s safety profile, paving the way for further exploration of CBD’s therapeutic applications and potential
adverse effects.
Keywords: cannabidiol, CBD, metabolism, cytotoxicity, genotoxicity, mutagenicity
Published in DiRROS: 09.07.2024; Views: 332; Downloads: 241
Full text (4,31 MB)
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