Darko Tibljas

Darko Tibljas

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Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2017 in Geoscience Frontiers
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Journal Article
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AGAnita Grizelj
Anita Grizelj
ZPZoran Peh
Zoran Peh
DTDarko Tibljas
Darko Tibljas
MKMarijan Kovačić
Marijan Kovačić
TKTomislav Kurečić
Tomislav Kurečić
Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica, Moslavačka Gora and Psunj Mts., and boreholes in the Sava Depression and the Požega Sub-depression were investigated. These sediments formed in different marine (with normal and reduced salinity), brackish, and freshwater environments, depending on the development stage of the Pannonian Basin System. Carbonate minerals, clay minerals and quartz are the main constituents of all pelitic sedimentary rocks, except in those from Moslavačka Gora Mt in which carbonate minerals are not present. Feldspars, pyrite, opal-CT, and hematite are present as minor constituents in some rocks. Besides calcite, dependent on the sedimentary environment and diagenetic changes, high-magnesium calcite, aragonite, dolomite and ankerite/Ca-dolomite are also present. Smectite or illite-smectite is the main clay minerals in the samples. Minor constituents, present in almost all samples, are detrital illite and kaolinite. In some samples chlorite is also present in a low amount. Major elements, trace elements and rare earth elements patterns used in provenance analysis show that all analysed samples have a composition similar to the values of the upper continental crust (UCC). The contents of major and trace elements as well as SiO2/Al2O3, K2O/Al2O3, Na2O/K2O, Eu/Eu*, La/Sc, Th/Sc, La/Co Th/Co, Th/Cr, Ce/Ce* and LREE/HREE ratios, show that the analysed pelitic sedimentary rocks were formed by weathering of different types of mostly acidic (silicic), i.e. felsic rocks

1 January 2022 in Palaeogeography, Palaeoclimatology, Palaeoecology
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Journal Article
Closed access
DPDavor Pavelić
Davor Pavelić
MKMarijan Kovačić
Marijan Kovačić
DTDarko Tibljas
Darko Tibljas
IGIvo Galić
Ivo Galić
FMFrane Marković
Frane Marković
IPIvica Pavičić
Ivica Pavičić


25 March 2021 in Coatings
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Journal Article
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DMDomagoj Mudronja
Domagoj Mudronja
FVFrederik Vanmeert
Frederik Vanmeert
SFStjepko Fazinić
Stjepko Fazinić
Koen Henri JanssensKoen Henri Janssens
Koen Henri Janssens
DTDarko Tibljas
Darko Tibljas
VDVladan Desnica
Vladan Desnica
Stone monuments and buildings are susceptible to weathering. Carbonate-based stones are especially vulnerable in acidic environments, whereas magmatic acidic stones are more susceptible to chemical weathering in basic environments. To slow down surface corrosion of limestone and marble artworks/buildings, protective coatings which inhibit calcite dissolution have been proposed. In this work, samples from two stone types with different porosity were treated with ammonium oxalate (AmOx) to create a protective layer of calcium oxalate (CaOx) using the previously developed brushing method. Two different synchrotron microscopy experiments were performed to determine its protective capability. X-ray powder diffraction (SR-μ-XRPD) in transmission geometry allowed visualization of the distributions of calcium carbonate and oxalates along the sample depths. In a second step, X-ray fluorescence (SR-μ-XRF) was used to check the efficiency/integrity of the protective surface coating layer. This was done by measuring the sulfur distribution on the stone surface after exposing the protected stones to sulfuric acid. XRPD showed the formation of a protective oxalate layer with a thickness of 5–15 µm on the less porous stone, while a 20–30 µm thick layer formed on the more porous stone. The XRF study showed that the optimal treatment time depends on the stone porosity. Increasing the treatment time from 1 to 3 h resulted in a decreased efficiency of the protective layer for the low porosity stone. We assume that this is due to the formation of vertical channels (cracks) in the protective layer.

13 February 2020 in Minerals
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Yulia MunYulia Mun
Yulia Mun
SPSabina Strmic Palinkas
Sabina Strmic Palinkas
MFMatthias Forwick
Matthias Forwick
JJJuho Junttila
Juho Junttila
KPKristine Pedersen
Kristine Pedersen
KKKåre Kullerud
Kåre Kullerud
Mine tailings that were produced during the exploitation of the Ulveryggen siliciclastic sediment-hosted Cu deposit in northern Norway were disposed into the inner part of Repparfjorden from 1972 to 1978/1979. This study focuses on the mineralogy and geochemistry of the submarine mine tailings and underlying natural marine sediments from the inner part of Repparfjorden, as well as on the primary Ulveryggen ore. The ore mineralization from the neighboring Nussir carbonate sediment-hosted Cu deposit was studied too, due to the forthcoming mining of both deposits. Bornite and chalcopyrite are the major Cu-sulfides, and are characterized by low concentrations of potentially toxic elements including Cd, Hg, and As. The tailing material occupies the uppermost 9 cm of Repparfjorden sediments. It is characterized by predomination of a silty component with elevated Cu (up to 747.7 ppm), Ni (up to 87 ppm), and Cr (up to 417 ppm) concentrations. The high Cu concentration is related to the deposition of mine tailings. In contrast, Ni and Cr concentrations are close to those in naturally occurring stream sediments from the feeding river, Repparfjordelva, reflecting the compatibility of these elements with hosting mafic volcanics, which are widely spread in the Repparfjord Tectonic Window. Copper in the uppermost part of the sediments is bound to the acid-soluble fraction while Ni and Cr are bound to the residual fraction. Artificial placement of large masses of fine-grained material, i.e., smothering, resulted in a diminished biological activity and/or physical distortion of mostly benthic fauna, which was reflected in total organic carbon (TOC) values as low as 0.15% in the uppermost strata. Sulfide minerals are found both in natural marine sediments and in the mine tailings. They are generally well-preserved with an exception for chalcopyrite from the uppermost part of the submarine tailing, which shows signs of incipient weathering. Thermodynamic modeling confirmed that redox potential and pH are important factors in the weathering of sulfides. Available ligands contribute to the Cu speciation. In near-neutral to slightly alkaline conditions a presence of carbonates can lead to the mobilization of Cu in form of CuCO3 complexes.

23 March 2011 in Environmental Earth Sciences
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Stanislav Frančišković-BilinskiStanislav Frančišković-Bilinski
Stanislav Frančišković-Bilinski
MJMladen Juračić
Mladen Juračić
DTDarko Tibljas
Darko Tibljas