Faculty of Mining, Geology and Petroleum Engineering Repository
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Competition of deltaic feeder systems reflected by slope progradation: a high-resolution example from the Late Miocene-Pliocene, Drava Basin, Croatia
No full textThe thick Lake Pannon sedimentary record provides insights into the downdip and lateral development of stratigraphic surfaces through the analysis of the basin-scale clinoform progradation. The clinoform architecture from the eastern part of the Drava Basin (Pannonian Basin System) was interpreted to reflect the base-level changes. A major downlap surface interpreted as a flooding event followed by rejuvenation of slope progradation was recognized on 2D seismic sections. Detailed 3D seismic interpretation combined with well data revealed that the large sigmoidal and the overlying small oblique clinoform sets that downlap the large one only apparently produce the geometry of a maximum flooding surface. Instead, the 3D mapping revealed the influence of two competing slope systems arriving from the north and northwest. Lateral switching of sediment input, similar to many recent deltaic systems. e.g., Danube and Po rivers led to the variability of stratigraphic surfaces, lithology, and thickness, which resulted in non-uniform shelf-edge migration. These observations were supported by forward stratigraphic modeling simulating different scenarios, which led to the generation of the depositional architecture with an apparent maximum flooding surface. This study also implies the potential pitfalls in basin analysis based only on scarce 2D seismic and emphasizes the role of lateral variations in sediment input controlling the depositional architecture
Abstracts / 23rd Scientic-Professional Colloquium on Geometry and Graphics, Vinkovci, 3-7 September 2023
No full textModel making of the development of mining works in the surface mine Valtura : master's thesis
No full textU diplomskom radu prikazan je razvoj rudarskih radova na površinskom kopu tehničko-građevnog kamena „Valtura“. Određeni su projektni parametri površinskog kopa pomoću kojih su izrađeni trodimenzionalni modeli razvoja rudarskih radova. Prikazan je napredak rudarskih radova kroz tri etape eksploatacije. Korištenjem računalnog programa „OpenRoads Designer“ prikazani su trodimenzionalni modeli terena i pojedinih etapa, a koristeći napredne funkcije navedenog računalnog programa proračunate su količine otkopanog materijala. Provedena je tehno-ekonomska ocjena isplativosti eksploatacije ležišta te je određeno vremensko trajanje izvođenja radova.This Master's Thesis presented a development of mining works in the open pit mine of crushed stone „Valtura“. Project parameters were determined by means of which the 3D models of mining works were created. The developmnet of mining works was shown through three stages of exploitation. Using computer program „OpenRoads Designer“ 3D models of terrain and stages were shown and using special features of the same computer program the quantities of excavated material were calculated. A techno-economic evaluation of the deposit's profitability was carried out and the duration of the works was determined
Estimation of groundwater reserves of the island of Hvar : master's thesis
No full textU ovome diplomskom radu prikazan je izračun procjene zaliha podzemne vode otoka Hvara. Izračun je proveden na temelju bilance vode gdje se promatra ulaz i izlaz vode iz nekog sustava. Korišteni su podaci količina oborine i temperature zraka za sedam odnosno dvije postaje. Također, u okviru rada provedena su i mjerenja razine podzemne vode u nekoliko navrata. Za godišnja razdoblja dobivene su maksimalne teoretske količine eksploatacijskih zaliha. Dodatno je za svaku godinu napravljen izračun za polugodišnja razdoblja s naglaskom na ljetne mjesece. Obzirom da veličina površine najviše utječe na procjenu zaliha, za crpilište Jelsa određeno je slivno područje na temelju topografije te litoloških i hidrogeoloških značajki naslaga.In this Master´s Thesis, calcultaion of the groundwater reserves of the island of Hvar, is presented. The calculation of water balance was carried out on the basis of precipitation and air temperature data sets from seven pluviometer´s station. Field measurements include data of groundwater levels from two piezometers. Results for annual periods of groundwater reserves are maximum theoretical possible values. In addition, calcualtions were made for half-year periods with focus on summer season. Calculations for catchment area of Jelsa well field represent better and more accurate results of groundwater reservs
Podrijetlo, ponašanje i modeliranje transporta nitrata u varaždinskom vodonosniku : doktorski rad
No full textOver the last decades, high nitrate concentrations in Varaždin alluvial aquifer raised public concern regarding groundwater quality. The aquifer is the main source of drinking water for the local population in the Varaždin County in NW Croatia. For better understanding of nitrate distribution in groundwater and formulating appropriate management strategies for groundwater quality protection, it is necessary to investigate the origin, fate, and transport of nitrate within the Varaždin aquifer. The conducted research combined different methods (hydraulic, geochemical, isotope, microbiological, statistical, modelling), which resulted in numerous findings about the alluvial aquifer, its interaction with surface water and precipitation, and nitrate behaviour within the aquifer. The stable water isotopes (δ18O and δ2H) indicated that groundwater and surface water are recharged by precipitation. The average estimated recharge from precipitation using Wetspass-M model was 34% of total precipitation. Analysis of head contour maps showed that aquifer is recharged from the Drava River and accumulation lake Varaždin, which was supported by stable water isotopes, and quantified by water budget analysis: surface waters participate in groundwater recharge with 68%, and precipitation infiltration with 32%. Dual isotopes of nitrate (δ15N and δ18O in NO3) indicated that manure, wastewater, soil organic N, and ammonia fertilizers are the possible sources of nitrate in groundwater. Chemical, isotope, bacterial, and hierarchical cluster analysis displayed grouping of wells in agricultural, urban, and natural area. Nitrification was identified as the main nitrogen transformation process, while denitrification can occur locally, but does not have significant impact on regional scale. The results of isotope mixing model showed that manure is the dominant nitrate source in agricultural, wastewater in urban, and soil organic N in natural group. The calibrated groundwater flow and nitrate transport model was used to simulate nitrate concentrations in groundwater in the next two decades. Model simulations predict continued downward trend of nitrate concentrations in the central part, and steady low nitrate concentrations in the northern part of the model. The modelling results demonstrated that management of agricultural practices is the most important aspect to gradually reduce nitrate contamination in the Varaždin aquifer, but it takes decades for nitrate concentrations in groundwater to respond to changes in nitrogen input from the surface.Tijekom posljednjih desetljeća visoke koncentracije nitrata u varaždinskom aluvijalnom vodonosniku izazvale su zabrinutost javnosti u pogledu kakvoće podzemnih voda. Vodonosnik je glavni izvor pitke vode za lokalno stanovništvo u Varaždinskoj županiji u sjeverozapadnoj Hrvatskoj. Radi boljeg razumijevanja raspodjele nitrata u podzemnoj vodi i formuliranja odgovarajućih strategija upravljanja za zaštitu kakvoće podzemne vode, neophodno je istražiti podrijetlo, ponašanje i transport nitrata unutar varaždinskog vodonosnika. U provedenim istraživanjima korištena je kombinacija različitih metoda (hidrauličke, geokemijske, izotopne, mikrobiološke, statističke, modeliranje), što je rezultiralo brojnim saznanjima o aluvijalnom vodonosniku, njegovoj interakciji s površinskim vodama i oborinama te ponašanju nitrata unutar vodonosnika. Tijekom četverogodišnjeg razdoblja, u sklopu terenskih istraživanja prikupljani su na mjesečnoj bazi uzorci podzemne i površinske vode za mjerenje osnovnih kationa i aniona, ukupnog i otopljenog organskog i anorganskog ugljika te analizu stabilnih izotopa kisika i vodika iz vode (δ18O i δ2H). Također, prikupljane su i mjesečne oborine na kišomjeru u Hrašćici za analizu δ18O i δ2H. Na terenu su povremeno uzimani uzorci za analizu stabilnih izotopa kisika δ18O i dušika δ15N u otopljenom nitratu u vodi, za analizu izotopa ugljika δ13C u vodi te za analizu bakterija u podzemnoj vodi. Uzorkovanje se provodilo tijekom različitih hidroloških i vegetacijskih ciklusa kako bi se pratile moguće sezonske promjene. Uz uzorke vode, uzeti su uzorci kultura koje se uzgajaju na varaždinskom području, tlo, sediment vodonosnika te gnojiva za analizu izotopa δ13C i δ15N u krutim tvarima. Rezultati stabilnih izotopa vode upućuju da oborine obnavljaju podzemne i površinske vode. Analiza karata ekvipotencijala pokazala je da se vodonosnik napaja iz rijeke Drave i akumulacijskog jezera Varaždin, što je potvrđeno stabilnim izotopima vode. Efektivna infiltracija oborine procijenjena je pomoću Wetspass-M modela te u prosjeku iznosi 34% od ukupne oborine. Analiza bilance vode pokazala je da površinske vode sudjeluju u napajanju podzemne vode sa 68%, dok infiltracija oborina ima sekundarni učinak s 32%. Dvostruki izotopi nitrata upućuju da su mogući izvori nitrata u podzemnoj vodi organska gnojiva, otpadne vode, organski dušik iz tla te gnojiva na bazi amonijaka. Kemijska, izotopna, bakterijska i hijerarhijska klaster analiza pokazale su grupiranje bušotina ovisno o načinu korištena zemljišta u poljoprivrednim, urbanim i prirodnim područjima. Nitrifikacija je identificirana kao glavni proces transformacije dušika, dok se denitrifikacija može dogoditi lokalno, ali nema značajan utjecaj u regionalnom mjerilu. Korištenjem izotopa δ15N-NO3, δ18O-NO3 i δ13C u modelu miješanja određeni su dominantni izvori nitrata u pojedinim grupama: organsko gnojivo u poljoprivrednim, otpadne vode u urbanim te organski dušik iz tla u prirodnim područjima. Kalibrirani model tečenja podzemne voda i transporta nitrata korišten je za simulaciju koncentracija nitrata u podzemnoj vodi u sljedećih 20 godina. Simulacije modela predviđaju nastavak silaznog trenda koncentracija nitrata u središnjem dijelu i stabilno niske koncentracije nitrata u sjevernom dijelu istraživanog područja. Rezultati modeliranja pokazali su da je upravljanje poljoprivrednim aktivnostima najučinkovitiji pristup postupnom smanjenju onečišćenja nitratima u varaždinskom vodonosniku. Međutim, potrebna su desetljeća da koncentracije nitrata u podzemnim vodama reagiraju na promjene u unosu dušika s površine pa pozitivne učinke bilo kakvih potencijalnih mjera treba očekivati nakon dužeg razdoblja
Engineering geological mapping of the north tube of the Učka Tunnel : master's thesis
No full textU okviru ovog diplomskog rada provedeno je inženjerskogeološko kartiranje i klasifikacija stijenske mase u sjevernoj cijevi Tunela Učka. Svrha inženjerskogeološkog kartiranja bila je zabilježiti sve geološke pojave, odrediti litologiju, definirati sve karakteristike stijenske mase te provesti odgovarajuću klasifikaciju. Klasifikacije korištene prilikom kartiranja stijenske mase su RMR (engl. Rock Mase Raiting) i Q klasifikacija. Tijekom praćenja podzemnog iskopa određeno je 26 geotehničkih jedinica koje uključuju kombinacije sedam litostratigrafskih i sedam strukturno-geoloških jedinica (tzv. strukturnih blokova). U ovom radu detaljno je opisano osam geotehničkih jedinica. Također je opisan posao inženjerskog geologa pri iskopu tunela, s osvrtom na najčešće probleme . Izrađen je uzdužni inženjerskogeološki profil sjeverne cijevi Tunela Učka od stacionaže 30+569,00 do 30+734,00, kako bi se prikazala dokumentacija inženjerskogeoloških istraživanja tijekom praćenja iskopa tunela.As part of this thesis, engineering geological mapping and classification of the rock mass in the northern tube of the Učka Tunnel was carried out. The purpose of engineering geological mapping was to record all geological phenomena, determine the lithology, define all the characteristics of the rock mass and carry out the appropriate classification. The classifications used during rock mass mapping are RMR (Rock Mass Rating) and Q classification. During the monitoring of the underground excavation, 26 geotechnical units were determined, which include combinations of seven lithostratigraphic 7 structural-geological units (so-called structural blocks). Eight geotechnical units are described in detail in this paper. The work of an engineering geologist during tunnel excavation is also described, with reference to the most common problems. A longitudinal engineering-geological profile of the northern tube of the Učka Tunnel was created from station 30+569,00 to 30+734,00 in order to present the documentation of engineering-geological research during the monitoring of tunnel excavation
Metallurgy of rare earth elements - winning and recycling
No full textThe workshop "Rare Earth Elements value chain gaps and opportunities in the ADRIA region" is organized as part of the EIT project RECO2MAG - Novel grain boundaries engineered resource efficient Nd-Fe-B permanent magnets (financed by EIT KIC Raw Material)
Utjecaj mehaničke stratigrafije na deformacijski stil u središnjem dijelu Vanjskih Dinarida: studija kinematskim 2D modeliranjem
No full textThe External Dinarides fold-thrust belt formed during Mid-Eocene – Oligocene times by SW-propagating thrusting from the Internal Dinarides towards the Adriatic foreland. Although previously considered as structurally quite uniform, recent work of BALLING et al. (2021) reported along-strike contrasting deformation styles in two structural domains within this fold-thrust belt. The two structural domains with very contrasting deformation styles are separated by the N-S-striking dextral Split–Karlovac Fault, a 250 km long, transpressive transfer fault. The southeastern domain is characterized by a thin-skinned SW-vergent nappe stack in contrast to the northwestern domain, where a set of blind, thick-skinned top-SW thrust duplexes prevail underneath the passive NE-vergent backthrusts. To better understand possible causes that controlled these contrasting along-strike deformation styles, we firstly analysed a spatial-temporal along- and across-strike distribution of Paleo-Mesozoic lithofacies to both sides of the Split-Karlovac Fault. We further estimated the role of mechanical stratigraphy on deformation styles in this part of the fold-thrust belt. This analysis was used to construct a new 2D kinematic forward model across the northwestern backthrust-dominated domain. Our best-fit forward-modelled balanced cross section traversing the central Velebit Mtn. portrays a 75 km wide triangle zone. This zone took up at least 47 km of shortening during Eo-Oligocene times. It comprises a set of thin-skinned NE-vergent backthrusts detached in the upper Paleozoic basement atop a SW-vergent thickskinned antiformal stack detached in the lower Paleozoic Adriatic basement. The NE-vergent backthrusts likely nucleated at lateral facies boundaries related to extensional half grabens that locally formed during Permian to Middle Triassic and Late Jurassic phases of a passive margin extension. During the Eo-Oligocene shortening, the selective inversion of inherited Mesozoic half grabens boundary faults into the NE-vergent backthrusts in the northwestern domain led to the observed along-strike changes in the deformation style of the External Dinarides. Thus, our results indicate that both the variations in the mechanical stratigraphy and the pre-orogenic structural inheritance obtained during rifting and passive margin stages exert control on Eocene–Oligocene contractional structures within the central part of the External Dinarides
Geomorfološki okoliši i tipovi klizišta na području grada Buzeta identificirani primjenom LiDAR digitalnoga modela reljefa
No full textThis study presents the results of landslide detection and mapping at a large scale, performed in the area of the city of Buzet in central Istria. The research was conducted within the frame of scientific research project “Methodology development for landslide susceptibility assessment for land-use planning based on LiDAR technology” (LandSlidePlan, HRZZ IP-2019-04-9900). The study area (20 km2) consists of Eocene flysch sediments, composed of a rhythmical alternation of marl and carbonate sediments in the lower part of the complex, and thinly bedded carbonate-siliciclastic turbidite sediments in the upper part (BERGANT et al., 2003). For the first time, the detailed geomorphological landslide inventory map (GUZZETTI et al., 2012) is created for the area in the flysch environment in central Istria, using innovative remote sensing technology that proved to be effective in mapping landslides (GÖRÜM, 2019; JAGODNIK et al., 2020a). Identification and mapping of landslides was carried out based on the visual interpretation of topographic datasets derived from the bare-earth LiDAR (Light Detection and Ranging) Digital Terrain Model (DTM) at a 0.3 m spatial resolution. Airborne laser scanning was performed in March 2020, with an average point density of 16 points per m2. In the study area, more than 1,160 landslides are identified and delineated with high geographical accuracy and thematic certainty due to the clear visibility of landslide features on LiDAR DTM derivatives. However, it was quite a challenge to identify and map individual landslides in areas of gully erosion and badlands, which represent the typical geomorphological phenomena in the flysch environment of central Istria (GULAM et al., 2014). Landslide density is 58 landslides per km2. Most of the landslides are debris slides, and debris slide-debris flows (HUNGR et al., 2014), which are the main types of landslides in flysch deposits ( JAGODNIK et al., 2020b). Landslides are predominantly small and shallow. Their sizes are in the range between only 4 m2 to 8 ha. Generally, there are three typical geomorphological settings of landslides in the study area: (i) complex gullies; (ii) agricultural fields; and (iii) artificial slopes along the roads. Gullies are the predominant environment for the occurrence of landslides, with approximately 65 % of identified landslides being situated in gullies. Such specific geomorphological setting of landslide phenomena confirmed that there is a significant interplay between mass movements and fluvial processes in the investigated area. Therefore, in the future research, the results of this study will be used for testing the relevance of gully and badland phenomena as conditioning factors in landslide susceptibility modelling at a large scale
Određivanje otpora vjetrene pregrade u rudniku Tehničkog muzeja Nikola Tesla : završni rad
No full textU ovom radu prikazano je određivanje otpora vjetrene pregrade u rudniku Tehničkog muzeja Nikola Tesla. U sklopu rada izmjeren je otpor pri šest različitih postavki otvora pregrade na vjetrenim vratima pri pet različitih brzina ventilatora. U rezultatima mjerenja vidljivo je da se postepenim zatvaranjem prigušnice povećava brzina strujanja zraka kroz samu prigušnicu dok se brzina strujanja u hodniku smanjuje. Na taj se način smanjenjem površine prigušnice postepeno povećava otpor strujanju zraka što uzrokuje postepeno povećanje pada tlaka na prigušnici