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Povzetek: Comprehensive glacial Quaternary studies involving geochronological methods, modelling of ice topography with the support of field geomorphological and geological data in the Balkan Peninsula are relatively scarce, although there is evidence of past glaciations in several mountain ranges. Here, we present research on the extent and timing of past glaciations on the northern Velebit Mt. in coastal Croatia and inferences of the climate during that time. Based on geomorphological and sedimentological evidence and using cosmogenic 36Cl surface exposure dating of moraine boulders, we provide an empirical reconstruction of past glaciers and compare this with the Parallel Ice Sheet Model (PISM) simulations under different palaeoclimate forcings. The dating results show that the northern Velebit glaciers reached their maximum extent during the last glacial cycle before the global Last Glacial Maximum (LGM). Maximum ice extent likely correlates with Marine Isotope Stage 5–4, although the exact timing cannot be determined at this point due to poorly known site- and time-specific denudation rates. Empirical reconstruction of the maximum extent suggests that the area covered by glaciers was ~116 km2. The-best fit PISM simulation indicates that the most likely palaeoclimate scenario for the glaciers of this size to form is a cooling of ~8 °C and a 10% reduction in precipitation from present-day levels. However, the best-fit simulation does not correctly model all mapped ice margins when changes in climatological parameters are applied uniformly across the model domain, potentially reflecting a different palaeoprecipitation pattern to today.
Ključne besede: Pleistocene, cosmogenic isotopes, glacial geomorphology, Dinarides, PISM
Objavljeno v DiRROS: 04.03.2022; Ogledov: 675; Prenosov: 256
Celotno besedilo (14,52 MB)

Povzetek: Aerosol vertical profiles are valuable inputs for the evaluation of aerosol transport models, in order to improve the understanding of aerosol pollution ventilation processes which drive the dispersion of pollutants in mountainous regions. With the aim of providing high-accuracy vertical distributions of particle mass concentration for the study of aerosol dispersion in small-scale valleys, vertical profiles of aerosol mass concentration for aerosols from different sources (including Saharan dust and local biomass burning events) were investigated over the Vipava valley, Slovenia, a representative hot-spot for complex mixtures of different aerosol types of both anthropogenic and natural origin. The analysis was based on datasets taken between 1–30 April 2016. In-situ measurements of aerosol size, absorption, and mass concentration were combined with lidar remote sensing, where vertical profiles of aerosol concentration were retrieved. Aerosol samples were characterized by SEM-EDX, to obtain aerosol morphology and chemical composition. Two cases with expected dominant presence of different specific aerosol types (mineral dust and biomass-burning aerosols) show significantly different aerosol properties and distributions within the valley. In the mineral dust case, we observed a decrease of the elevated aerosol layer height and subsequent spreading of mineral dust within the valley, while in the biomass-burning case we observed the lifting of aerosols above the planetary boundary layer (PBL). All uncertainties of size and assumed optical properties, combined, amount to the total uncertainty of aerosol mass concentrations below 30% within the valley. We have also identified the most indicative in-situ parameters for identification of aerosol type.
Ključne besede: valley air pollution, aerosol vertical distributions, lidar remote sensing, in-situ measurements, aerosol identification
Objavljeno v DiRROS: 03.03.2022; Ogledov: 770; Prenosov: 286
Povezava na celotno besedilo

Povzetek: Krk Island located in the Dinaric karst is characterized by somewhat contradictory, yet undefined depressions of linear geometry. A comprehensive spatial analysis considering over 900 linear features served as a testing ground for revealing the specific circumstances required for the occurrence of the linear morphology on the surface of rather pure karst typically characterized by dolines. Morphological characteristics, spatial distribution and field evidence imply that linear features of different appearance are the outcome of several different mechanisms including speleogenesis and denudation, slope processes and erosion by the torrential surface runoff. Surface runoff occurred due to specific regional geological, morphological and climate conditions in the area. Recently, such linear features exhibit a dry valley- or dry gorge-like appearance. This example from the Dinarides provides insight into the possible circumstances that may cause a temporal surface runoff even in rather pure karst conditions. This knowledge is valuable for understanding other karst areas expressing temporal surface runoff or imprints of its past occurrences.
Ključne besede: kras, geomorfologija, prostorska analiza, suhe kraške doline, linearne oblike
Objavljeno v DiRROS: 03.03.2022; Ogledov: 701; Prenosov: 304
Celotno besedilo (4,24 MB)

Povzetek: Mining waste deposits (MWDs) represent significant and constant pollution source for the environment worldwide, thus it is very important to identify and diminish their environmental impacts. The aim of this study was to determine long-term environmental impacts and their temporal variations of MWDs in Pb–Zn mining districts in Slovenia and assess stability of potentially harmful element (PHE)-bearing phases in stream water. The results showed that investigated MWDs are important source of PHEs in stream sediments and that PHEs mostly occur as fine-grained and liberated PHE-bearing ore minerals. MWDs have generally stronger impact on sediments of smaller streams draining MWDs and main streams close to their confluences, however, fine-grained PHE-bearing material is transported along major watercourses over long distances causing regional pollution. Main ore minerals are mostly soluble in stream water. However, measured PHE leaching potential of MWDs is negligible. PHE levels in stream waters are thus low, demonstrating that drainage of MWDs predominantly contributes to PHE pollution in solid particulate form. Possible long-term remediation solution that would reduce environmental impact is recovery of metals from fine grain size fractions of MWDs, which could become an effective practice in sustainable management of historical MWDs. However, further studies of MWDs’ secondary resource potential, processing technology and evaluation of environmental aspects of extraction are needed.
Ključne besede: metals, stream sediment, stream water, characterisation, mineral solubility
Objavljeno v DiRROS: 03.03.2022; Ogledov: 701; Prenosov: 514
Celotno besedilo (19,64 MB)

Povzetek: UNEXUP is a direct continuation of the UNEXMIN project. In UNEXMIN efforts were made towards the design, development and testing of a robotic exploration technology for underground flooded mines, with navigational and geoscientific instruments. In UNEXUP the main goal is to raise commercial interest and improve the system's hardware, software and capabilities. The UX-1 NEO, to be developed and tested in 2020, will address the limitations detected during UNEXMIN field missions, and will meet the needs and requirements from mining companies, geological surveys and other potential customers. In addition, a new robot will be built and added to the system, to be ready in 2021, which will open further mineral exploration possibilities.
Objavljeno v DiRROS: 07.01.2021; Ogledov: 1483; Prenosov: 716
Celotno besedilo (1,68 MB)