D. Palenik, Dubravko Matičec, Ladislav Fuček, B. Matos, M. Herak, Igor Vlahović
The area of the Vinodol Valley and Bakar Bay represents a NW‒SE oriented valley in the NW Adriatic characterised by prominent historical and instrumentally recorded seismicity. As part of the greater geodynamic domain including the Ilirska Bistrica–Rijeka–Senj seismogenic fault zone, new geological and structural data addressing the tectonic evolution of the area were collected in order to better understand the focal mechanisms of previous earthquakes and to enable identification of potential seismogenic sources. Mapped informal lithostratigraphic units mostly correspond to the Upper Cretaceous, Palaeogene and Quaternary successions described in other parts of the External Dinarides. However, a shorter stratigraphic range of the Gornji Humac fm., the youngest Cretaceous unit in the study area, was determined and suggests that the uplifted area in the central NW part of the Adriatic Carbonate Platform already comprised several thousand km2 (from W and NW Istria to Krk and Vinodol area) at the end of the Turonian. Structural measurements of the fault planes in the study area generally correspond to the existing structural model of the tectonic evolution of the Dinarides. However, in contrast to the SW vergences typical of the Dinarides, NE-vergent reverse structures are common, especially along the SW margin of the Vinodol Valley. Cross-cutting relationships suggest that transpressional (NW–SE and NE–SW striking dextral and sinistral faults) and extensional features (NW–SE and NE–SW striking normal faults) are structurally concurrent or younger than the reverse faults, suggesting a change in the palaeostress field during the Neogene–Quaternary, with prevalent transpression and radial extension. Comparison of results of the palaeostress field analysis and the constructed synthetic focal mechanisms on one side, with available focal mechanism solutions for earthquakes within the Ilirska Bistrica–Rijeka–Senj seismogenic fault zone on the other, shows a favourable orientation of the observed NW‒SE and NE‒SW striking faults with respect to the recent compressional/transpressional stress field (N‒S oriented P-axis), indicating these as potential seismogenic sources within the study area.
{"title":"Geological and structural setting of the Vinodol Valley (NW Adriatic, Croatia): insights into its tectonic evolution based on structural investigations","authors":"D. Palenik, Dubravko Matičec, Ladislav Fuček, B. Matos, M. Herak, Igor Vlahović","doi":"10.4154/gc.2019.13","DOIUrl":"https://doi.org/10.4154/gc.2019.13","url":null,"abstract":"The area of the Vinodol Valley and Bakar Bay represents a NW‒SE oriented valley in the NW Adriatic characterised by prominent historical and instrumentally recorded seismicity. As part of the greater geodynamic domain including the Ilirska Bistrica–Rijeka–Senj seismogenic fault zone, new geological and structural data addressing the tectonic evolution of the area were collected in order to better understand the focal mechanisms of previous earthquakes and to enable identification of potential seismogenic sources. \u0000Mapped informal lithostratigraphic units mostly correspond to the Upper Cretaceous, Palaeogene and Quaternary successions described in other parts of the External Dinarides. However, a shorter stratigraphic range of the Gornji Humac fm., the youngest Cretaceous unit in the study area, was determined and suggests that the uplifted area in the central NW part of the Adriatic Carbonate Platform already comprised several thousand km2 (from W and NW Istria to Krk and Vinodol area) at the end of the Turonian. \u0000Structural measurements of the fault planes in the study area generally correspond to the existing structural model of the tectonic evolution of the Dinarides. However, in contrast to the SW vergences typical of the Dinarides, NE-vergent reverse structures are common, especially along the SW margin of the Vinodol Valley. Cross-cutting relationships suggest that transpressional (NW–SE and NE–SW striking dextral and sinistral faults) and extensional features (NW–SE and NE–SW striking normal faults) are structurally concurrent or younger than the reverse faults, suggesting a change in the palaeostress field during the Neogene–Quaternary, with prevalent transpression and radial extension. Comparison of results of the palaeostress field analysis and the constructed synthetic focal mechanisms on one side, with available focal mechanism solutions for earthquakes within the Ilirska Bistrica–Rijeka–Senj seismogenic fault zone on the other, shows a favourable orientation of the observed NW‒SE and NE‒SW striking faults with respect to the recent compressional/transpressional stress field (N‒S oriented P-axis), indicating these as potential seismogenic sources within the study area.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43365410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study presents the first attempt to estimate the palaeo-depth, and to assess the environmental conditions at the sea bottom, by means of foraminifers during the deposition of earlier Badenian deposits in the North Croatian Basin. The studied stratigraphic record, the Glavnica Gornja section is located in Mt. Medvednica, in the southwestern part of the Pannonian Basin System, and it belongs to the Upper Lagenidae Zone (Moravian substage of the Badenian). Three methods were tested to estimate the palaeo-depth; the plankton/benthos (P/B) ratio indicated the lower to upper bathyal zone, the modified P/B ratio indicated 886-987 m depth for the bathyal zone, whereas the Hohenegger method indicated 142-204 m depth for the outer shelf. Of the three estimates, the last is considered as best fitting the general environmental demands of the dominant and common small benthic forams. The well oxygenated sea bottom was temporarily replaced by more stressful conditions in the middle part of the studied interval, pointing to occasional variations in the organic flux.
{"title":"Foraminifera – based estimation of water depth in epicontinental seas: Badenian deposits from Glavnica Gornja (Medvednica Mt., Croatia), Central Paratethys","authors":"Đurđica Pezelj, Lucija Drobnjak","doi":"10.4154/GC.2019.08","DOIUrl":"https://doi.org/10.4154/GC.2019.08","url":null,"abstract":"This study presents the first attempt to estimate the palaeo-depth, and to assess the environmental conditions at the sea bottom, by means of foraminifers during the deposition of earlier Badenian deposits in the North Croatian Basin. The studied stratigraphic record, the Glavnica Gornja section is located in Mt. Medvednica, in the southwestern part of the Pannonian Basin System, and it belongs to the Upper Lagenidae Zone (Moravian substage of the Badenian). Three methods were tested to estimate the palaeo-depth; the plankton/benthos (P/B) ratio indicated the lower to upper bathyal zone, the modified P/B ratio indicated 886-987 m depth for the bathyal zone, whereas the Hohenegger method indicated 142-204 m depth for the outer shelf. Of the three estimates, the last is considered as best fitting the general environmental demands of the dominant and common small benthic forams. The well oxygenated sea bottom was temporarily replaced by more stressful conditions in the middle part of the studied interval, pointing to occasional variations in the organic flux.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46081466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. Festa, F. Giosa, M. Moretti, V. Gaudio, P. Pierri
The portion of the southern Adriatic Sea, adjacent to the Murge area (Apulian Foreland, Southern Italy), is considered mainly aseismic. The recent March 23rd 2018 earthquake (Mw 3.7), occurred near Brindisi (Puglia Region), giving us occasion to reconsider data coming from different sources (instrumentally-recorded, historically-documented and palaeoseismologically-interpreted earthquakes), that suggest some moderate seismic shocks in this portion of the Adriatic Sea. The present study, based on the re-interpretation of public domain seismic profiles and exploration well logs available in the ViDEPI Project, has been focused on the recognition of faults with Quaternary activity in the epicentral area. A S-dipping fault, with a main dip-slip component of movement, is suggested to be the seismogenic source. Its geometry is consistent with the fault plane solution and the depth of the hypocenter calculated by the INGV (Istituto Nazionale di Geofisica e Vulcanologia).
亚得里亚海南部的部分，毗邻穆尔热地区(意大利南部的阿普利安前陆)，被认为主要是地震。最近的2018年3月23日发生在布林迪西(普利亚地区)附近的地震(3.7 Mw)，使我们有机会重新考虑来自不同来源的数据(仪器记录，历史记录和古地震解释的地震)，这些数据表明亚得里亚海的这一部分发生了一些中等地震冲击。本研究基于ViDEPI项目对公共域地震剖面和勘探测井资料的重新解释，重点关注震源区域第四纪活动断层的识别。一条以倾滑运动为主的s向断层可能是孕震源。其几何形状与INGV (Istituto Nazionale di Geofisica e Vulcanologia)计算的断裂面解和震源深度一致。
{"title":"In search of the seismogenic fault of the March 23rd 2018 earthquake (Mw 3.7) near Brindisi (Puglia, Southern Italy)","authors":"V. Festa, F. Giosa, M. Moretti, V. Gaudio, P. Pierri","doi":"10.4154/GC.2019.10","DOIUrl":"https://doi.org/10.4154/GC.2019.10","url":null,"abstract":"The portion of the southern Adriatic Sea, adjacent to the Murge area (Apulian Foreland, Southern Italy), is considered mainly aseismic. The recent March 23rd 2018 earthquake (Mw 3.7), occurred near Brindisi (Puglia Region), giving us occasion to reconsider data coming from different sources (instrumentally-recorded, historically-documented and palaeoseismologically-interpreted earthquakes), that suggest some moderate seismic shocks in this portion of the Adriatic Sea. The present study, based on the re-interpretation of public domain seismic profiles and exploration well logs available in the ViDEPI Project, has been focused on the recognition of faults with Quaternary activity in the epicentral area. A S-dipping fault, with a main dip-slip component of movement, is suggested to be the seismogenic source. Its geometry is consistent with the fault plane solution and the depth of the hypocenter calculated by the INGV (Istituto Nazionale di Geofisica e Vulcanologia).","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45363302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In biostratigraphic research of the Upper Miocene of Pannonian basin system, one of the frequently detected and important ostracod genera is Hemicytheria POKORNÝ (1955). Among more than 20 species of this genus, Hemicytheria setosa is present in sandy facies of the Lake Pannon sediments in Serbia and Bosnia and Herzegovina. The aims of this study were to describe sexual dimorphism and differences between left and right valve morphology in Hemicytheria setosa. Landmark based geometric morphometrics is applied on the grounds of existence of the homologue pattern of the fossae and pore conuli on the valve surface of this group of ostracods. Significant differences between sexes and between left and right valves are detected in the present study. The obtained results indicate that applied methods and chosen landmarks could be useful in the studies of valve ornamentation-variation in fossil and recent Ostracoda.
{"title":"Sexual dimorphism and left-right asymmetry of carapace ornamentation in Hemicytheria setosa RUNDIĆ 2002","authors":"Vukica D. Vujić, L. Rundić, T. Karan-Žnidaršič","doi":"10.4154/GC.2019.07","DOIUrl":"https://doi.org/10.4154/GC.2019.07","url":null,"abstract":"In biostratigraphic research of the Upper Miocene of Pannonian basin system, one of the frequently detected and important ostracod genera is Hemicytheria POKORNÝ (1955). Among more than 20 species of this genus, Hemicytheria setosa is present in sandy facies of the Lake Pannon sediments in Serbia and Bosnia and Herzegovina. The aims of this study were to describe sexual dimorphism and differences between left and right valve morphology in Hemicytheria setosa. Landmark based geometric morphometrics is applied on the grounds of existence of the homologue pattern of the fossae and pore conuli on the valve surface of this group of ostracods. Significant differences between sexes and between left and right valves are detected in the present study. The obtained results indicate that applied methods and chosen landmarks could be useful in the studies of valve ornamentation-variation in fossil and recent Ostracoda.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44722098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Rundić, Meri Ganić, S. Kneževič, D. Radivojević, M. Radonjić
Mt. Avala is located on the southern margin of the Pannonian basin (SPB), a border zone between the uplifted morphostructures of the Dinarides and Carpathian-Balkanides. Similar to the Pannonian basin, tectonostratigraphic evolution of the Mt. Avala area during the last 23 Ma has is characterized by syn- and post-rifting processes as well as tectonic inversion. Here, we present the results of field investigations of the Miocene‒Pliocene dynamics that led to different spatial positions of the same stratigraphic units (e.g. Badenian and Pannonian) in a relatively small area. These spatial relationships are interpreted in the context of pronounced block structures (Torlak, Beli Potok and Avala). Torlak Hill represents a horst structure with a core composed of Mesozoic rocks and hillsides composed of the Middle Miocene sediments, which are present at the surface at altitudes up to 336 metres. Nearby, there is the Beli Potok asymmetrical trough that was infilled by the late Miocene sediments. The Torlak horst and the Beli Potok trough structures are separated by the Rakovica normal fault. In some places along the fault line, several geological units are vertically displaced more than a hundred metres. For example, in borehole KGK-14, the Upper Miocene Pannonian marls are observed at a depth of 100 metres below the surface. However, only a few hundred metres away to the northeast, similar Pannonian marls are observed at the surface, at an altitude of about 210 metres. Due to the mentioned observed vertical movements along the block structures, a composite hilly relief with dominant the Torlak Hill and the Beli Potok Valley was formed.
{"title":"Stratigraphic implications of the Mio-Pliocene geodynamics in the area of Mt. Avala: new evidence from Torlak Hill and Beli Potok (Belgrade, Serbia)","authors":"L. Rundić, Meri Ganić, S. Kneževič, D. Radivojević, M. Radonjić","doi":"10.4154/GC.2019.11","DOIUrl":"https://doi.org/10.4154/GC.2019.11","url":null,"abstract":"Mt. Avala is located on the southern margin of the Pannonian basin (SPB), a border zone between the uplifted morphostructures of the Dinarides and Carpathian-Balkanides. Similar to the Pannonian basin, tectonostratigraphic evolution of the Mt. Avala area during the last 23 Ma has is characterized by syn- and post-rifting processes as well as tectonic inversion. Here, we present the results of field investigations of the Miocene‒Pliocene dynamics that led to different spatial positions of the same stratigraphic units (e.g. Badenian and Pannonian) in a relatively small area. These spatial relationships are interpreted in the context of pronounced block structures (Torlak, Beli Potok and Avala). Torlak Hill represents a horst structure with a core composed of Mesozoic rocks and hillsides composed of the Middle Miocene sediments, which are present at the surface at altitudes up to 336 metres. Nearby, there is the Beli Potok asymmetrical trough that was infilled by the late Miocene sediments. The Torlak horst and the Beli Potok trough structures are separated by the Rakovica normal fault. In some places along the fault line, several geological units are vertically displaced more than a hundred metres. For example, in borehole KGK-14, the Upper Miocene Pannonian marls are observed at a depth of 100 metres below the surface. However, only a few hundred metres away to the northeast, similar Pannonian marls are observed at the surface, at an altitude of about 210 metres. Due to the mentioned observed vertical movements along the block structures, a composite hilly relief with dominant the Torlak Hill and the Beli Potok Valley was formed.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42797281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Krsko-Brežice field is one of the most seismically active areas in Slovenia. The most damaging recorded earthquake with an intensity of VIII (EMS) occurred on 29th January 1917. It caused damage and claimed two lives. In the last 100 years, 9 earthquakes with intensity higher than VI (EMS) have been recorded. At the investigated area, a top layer up to 5 m thick, consisting of recent deposit of very loose silts and sands (ML, SM, SP), covers the medium dense to dense Quaternary gravel, beneath which there are over-consolidated, uncemented Miocene silts and marls. The top layer could be prone to liquefaction, as reported for the close surroundings of Brežice, where the liquefaction phenomenon was observed during the Zagreb earthquake in 1880 and during the Kupa Valley earthquake in 1909. The paper presents the results of laboratory index tests, cyclic simple shear tests and field investigations (SPT, CPT, (S)DMT, vs measurements), which were carried out to assess the liquefaction potential of the top layer at the location of the Brežice Hydroelectric Power Plant (HPP). All results show that the top layer is prone to liquefaction for an earthquake with a 475 year return period. Cyclic simple shear test results show that the liquefaction potential of horizontal ground for an earthquake with a 475 year return period can be reduced by the densification of the top layer to at least 95% of maximum Proctor density.
{"title":"Liquefaction potential of sands at the Krško-Brežice field, Slovenia","authors":"J. Smolar, M. Maček, A. Petkovšek","doi":"10.4154/GC.2019.12","DOIUrl":"https://doi.org/10.4154/GC.2019.12","url":null,"abstract":"The Krsko-Brežice field is one of the most seismically active areas in Slovenia. The most damaging recorded earthquake with an intensity of VIII (EMS) occurred on 29th January 1917. It caused damage and claimed two lives. In the last 100 years, 9 earthquakes with intensity higher than VI (EMS) have been recorded. \u0000At the investigated area, a top layer up to 5 m thick, consisting of recent deposit of very loose silts and sands (ML, SM, SP), covers the medium dense to dense Quaternary gravel, beneath which there are over-consolidated, uncemented Miocene silts and marls. The top layer could be prone to liquefaction, as reported for the close surroundings of Brežice, where the liquefaction phenomenon was observed during the Zagreb earthquake in 1880 and during the Kupa Valley earthquake in 1909. \u0000The paper presents the results of laboratory index tests, cyclic simple shear tests and field investigations (SPT, CPT, (S)DMT, vs measurements), which were carried out to assess the liquefaction potential of the top layer at the location of the Brežice Hydroelectric Power Plant (HPP). All results show that the top layer is prone to liquefaction for an earthquake with a 475 year return period. Cyclic simple shear test results show that the liquefaction potential of horizontal ground for an earthquake with a 475 year return period can be reduced by the densification of the top layer to at least 95% of maximum Proctor density.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70280983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Vladimir Šaraba, S. Popović, V. Obradović, Jana Štrbački, V. Gajić, P. Vulić, G. Šimić, O. Krunić
Investigations focusing on wellhead encrustations within select zones of emergence of mineral water, in different hydrogeological provinces, were conducted from 2014 to 2017 in Serbia. They included: well BB-1 in Bogatic (Inner Dinaric Alps of western Serbia), wells LB-4 and LB-5 in Lukovska Banja (Sumadija-Kopaonik-Kosovo Province), and wells VG-2 and VG-3 in Vranjska Banja (Serbian Crystalline Core). The studied occurrences belong to the group of hot mineral waters, with temperatures ranging from 62°C to 93.9°C, and total dissolved solids (TDS) from 600 to 1267 mg/L. They are mildly acidic to mildly alkaline (pH 6.6 – 8.0) and their genetic types are HCO3--Na++K+ (Bogatic and Lukovska Banja) and SO42-, HCO3--Na++K+ (Vranjska Banja). Macroscopic, optical and diffraction assessment revealed that the encrustations comprised calcite and aragonite minerals, along with some local quartz, muscovite, albite and clinochlore. The conclusion was that there was a predominant presence of calcium carbonate in all the occurrences, represented by crystalline calcite grains, characteristically birefractive, and dark, semitranslucent grains in the form of microcrystalline calcite highly stained by iron hydroxides (Bogatic), as well as crystalline calcite with radially developed carbonate - aragonite (Lukovska Banja) and rod-like and filamentous aggregates of aragonite and calcite, highly translucent in places (Vranjska Banja).The texture of the samples exhibits alternating horizontal or wavy carbonate laminae. In Vranjska Banja, they include thin micritic to medium crystalline laminae and laminae composed of aggregates of aragonite needles in the form of bunch. In Bogatic and Lukovska Banja, there are thick micritic and highly porous laminae, 0.025 to 1 mm thick, or interlayers of a coarser crystalline structure. Apart from encrustations, all the occurrences exhibit phototrophic microbial mats, which were analyzed by scanning electron microscopy. The onset and progress of encrustation are primarily influenced by the physical and chemical composition of the mineral water (T, pH, TDS, HCO3-, Ca2+, CO2, etc.), as corroborated by hydrogeochemical modeling software PHREEQC 3.4.0. In addition, phototrophic biofilms might be contributing to the creation and accumulation of minerals in the encrustations.
{"title":"Macroscopic, optical and diffraction assessment of encrustations and SEM analyses of phototrophic microbial mats from wellheads and select zones of emergence of mineral water in Serbia","authors":"Vladimir Šaraba, S. Popović, V. Obradović, Jana Štrbački, V. Gajić, P. Vulić, G. Šimić, O. Krunić","doi":"10.4154/GC.2019.09","DOIUrl":"https://doi.org/10.4154/GC.2019.09","url":null,"abstract":"Investigations focusing on wellhead encrustations within select zones of emergence of mineral water, in different hydrogeological provinces, were conducted from 2014 to 2017 in Serbia. They included: well BB-1 in Bogatic (Inner Dinaric Alps of western Serbia), wells LB-4 and LB-5 in Lukovska Banja (Sumadija-Kopaonik-Kosovo Province), and wells VG-2 and VG-3 in Vranjska Banja (Serbian Crystalline Core). The studied occurrences belong to the group of hot mineral waters, with temperatures ranging from 62°C to 93.9°C, and total dissolved solids (TDS) from 600 to 1267 mg/L. They are mildly acidic to mildly alkaline (pH 6.6 – 8.0) and their genetic types are HCO3--Na++K+ (Bogatic and Lukovska Banja) and SO42-, HCO3--Na++K+ (Vranjska Banja). Macroscopic, optical and diffraction assessment revealed that the encrustations comprised calcite and aragonite minerals, along with some local quartz, muscovite, albite and clinochlore. The conclusion was that there was a predominant presence of calcium carbonate in all the occurrences, represented by crystalline calcite grains, characteristically birefractive, and dark, semitranslucent grains in the form of microcrystalline calcite highly stained by iron hydroxides (Bogatic), as well as crystalline calcite with radially developed carbonate - aragonite (Lukovska Banja) and rod-like and filamentous aggregates of aragonite and calcite, highly translucent in places (Vranjska Banja).The texture of the samples exhibits alternating horizontal or wavy carbonate laminae. In Vranjska Banja, they include thin micritic to medium crystalline laminae and laminae composed of aggregates of aragonite needles in the form of bunch. In Bogatic and Lukovska Banja, there are thick micritic and highly porous laminae, 0.025 to 1 mm thick, or interlayers of a coarser crystalline structure. Apart from encrustations, all the occurrences exhibit phototrophic microbial mats, which were analyzed by scanning electron microscopy. The onset and progress of encrustation are primarily influenced by the physical and chemical composition of the mineral water (T, pH, TDS, HCO3-, Ca2+, CO2, etc.), as corroborated by hydrogeochemical modeling software PHREEQC 3.4.0. In addition, phototrophic biofilms might be contributing to the creation and accumulation of minerals in the encrustations.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46368305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Životić, O. Cvetković, P. Vulić, I. Grzetic, V. Šimić, Konstantin Ilijevic, B. Dojčinović, S. Erić, B. Radic, S. Stojadinovic, S. Trifunović
A geochemical and mineralogical study was performed on lignite samples from the Upper Miocene Kovin deposit, hosting three coal seams. The Kovin lignite is characterized by high moisture content, medium to high ash yield, medium to high sulphur content and a relatively low gross and net calorific value. The mineralogical composition, and major and trace element contents were determined by X-ray diffraction, scanning electron microscopy with energy dispersive Xray spectroscopy (SEM-EDS) analyses, and inductively coupled plasma optical emission spectrometry (ICP-OES). The most abundant minerals in all lignite samples from the three coal seams are clays (illite/smectite), silicates (quartz, plagioclase), sulphates (gypsum/anhydrite) and carbonate (calcite). The other iron-rich minerals are sulphides, oxides and hydroxides (pyrite, magnetite, haematite, and limonite). In general, mineral matter in the matrix coal consists of illite/ smectite and quartz, while xylite-rich coals, apart from illite/smectite, have a higher content of sulphates and Fe-oxide/hydroxide minerals. The lignite from the Kovin deposit is enriched in As, Cd, Co, Cr, Cu, Ga, Li, Mn, Mo, Ni, Pb, V, Zn, Gd, Tb, Er and Lu in comparison with the Clarke values for brown coals. The statistical analysis of bulk compositional data shows inorganic affinity for the majority of the major and trace elements and possible association with pyrite, illite/ smectite and calcite.
{"title":"Distribution of major and trace elements in the Kovin lignite (Serbia)","authors":"D. Životić, O. Cvetković, P. Vulić, I. Grzetic, V. Šimić, Konstantin Ilijevic, B. Dojčinović, S. Erić, B. Radic, S. Stojadinovic, S. Trifunović","doi":"10.4154/GC.2019.06","DOIUrl":"https://doi.org/10.4154/GC.2019.06","url":null,"abstract":"A geochemical and mineralogical study was performed on lignite samples from the Upper Miocene Kovin deposit, hosting three coal seams. The Kovin lignite is characterized by high moisture content, medium to high ash yield, medium to high sulphur content and a relatively low gross and net calorific value. The mineralogical composition, and major and trace element contents were determined by X-ray diffraction, scanning electron microscopy with energy dispersive Xray spectroscopy (SEM-EDS) analyses, and inductively coupled plasma optical emission spectrometry (ICP-OES). The most abundant minerals in all lignite samples from the three coal seams are clays (illite/smectite), silicates (quartz, plagioclase), sulphates (gypsum/anhydrite) and carbonate (calcite). The other iron-rich minerals are sulphides, oxides and hydroxides (pyrite, magnetite, haematite, and limonite). In general, mineral matter in the matrix coal consists of illite/ smectite and quartz, while xylite-rich coals, apart from illite/smectite, have a higher content of sulphates and Fe-oxide/hydroxide minerals. The lignite from the Kovin deposit is enriched in As, Cd, Co, Cr, Cu, Ga, Li, Mn, Mo, Ni, Pb, V, Zn, Gd, Tb, Er and Lu in comparison with the Clarke values for brown coals. The statistical analysis of bulk compositional data shows inorganic affinity for the majority of the major and trace elements and possible association with pyrite, illite/ smectite and calcite.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4154/GC.2019.06","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44922731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Marić, Danica Srećković-Batoćanin, N. Vasić, Marija Radisavljević, Tatjana Đekić
The petrological and geochemical composition of Neogene lacustrine successions and basement rocks of the Belanovica basin in Central Serbia, were investigated in three exploration boreholes, drilled in the central part of the former lake. Two boreholes accessed the basement, while the third one terminated in the lowermost Neogene interval, composed of coarse-grained clastics. Formation and diversification of the lake basin was influenced by strong syndepositional volcanic activity. The vertical distribution of selected elements from basal clastics (Cr, Ni, and Mg) and from overlying lake sediments (Ba, Sr, Na, K, etc.) indicates both the southern and northern margins of the basin, as potential source areas. The elemental concentrations are consistent with petrography. Based on the derived data, a reconstruction of the basin history is presented. The lack of index fossils resulted in a less accurate stratigraphy and the need for further updating by employment of the fission-track low-temperature thermochronometers. Additionally, outcrop studies and correlation with lake sediments in the Valjevo-Mionica basin is suggested.
{"title":"History of the Belanovica (Serbia) Neogene lake basin inferred from petrological and geochemical data","authors":"D. Marić, Danica Srećković-Batoćanin, N. Vasić, Marija Radisavljević, Tatjana Đekić","doi":"10.4154/GC.2019.05","DOIUrl":"https://doi.org/10.4154/GC.2019.05","url":null,"abstract":"The petrological and geochemical composition of Neogene lacustrine successions and basement rocks of the Belanovica basin in Central Serbia, were investigated in three exploration boreholes, drilled in the central part of the former lake. Two boreholes accessed the basement, while the third one terminated in the lowermost Neogene interval, composed of coarse-grained clastics. Formation and diversification of the lake basin was influenced by strong syndepositional volcanic activity. The vertical distribution of selected elements from basal clastics (Cr, Ni, and Mg) and from overlying lake sediments (Ba, Sr, Na, K, etc.) indicates both the southern and northern margins of the basin, as potential source areas. The elemental concentrations are consistent with petrography. Based on the derived data, a reconstruction of the basin history is presented. The lack of index fossils resulted in a less accurate stratigraphy and the need for further updating by employment of the fission-track low-temperature thermochronometers. Additionally, outcrop studies and correlation with lake sediments in the Valjevo-Mionica basin is suggested.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":"1 1","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41563301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Howari, Fatima Al Aydaroos, Y. Nazzal, J. Iqbal, Nadine Bou Orm
This paper describes simultaneous uses of field sampling and hyperspectroscopic approaches to understand the distributions of salt crusts and factors affecting them under field conditions. Samples of salt affected soils and associated salt crusts that represented a range of soil salinities, slope, and moisture contents were gathered from the banks of the Rio Grande. The samples were studied for salt identification by optical microscopy and using a high-resolution spectroradiometer, GER 3700, and for salinity level, and moisture content by the wet chemistry method. The study identified two main groups of salt crusts, contaminated halite and gypsum crusts. Reflectivity was correlated negatively with moisture content and positively with slope value, electrical conductivity and salt quantity. Reflectivity of halite-dominated crusts was higher than those of gypsum. Halite occurred over a greater range and higher slope values of soils than gypsum; however, a positive correlation between the slope and mean reflectivity of both salt crusts was reported. Although reflectivity of salt crusts varied according to changes in moisture content, and the salinity of the soil, moisture content can drastically reduce the reflection more effectively? than the other factors. The data reported indicate the possibility of assessing the type of salt crust by estimation of the ratio of slope and reflectivity to the other variables.
{"title":"Hyperspectroscopic and microtopographic analyses of salt crust forms on arid, silty clay loam desert soils","authors":"F. Howari, Fatima Al Aydaroos, Y. Nazzal, J. Iqbal, Nadine Bou Orm","doi":"10.4154/GC.2019.01","DOIUrl":"https://doi.org/10.4154/GC.2019.01","url":null,"abstract":"This paper describes simultaneous uses of field sampling and hyperspectroscopic approaches to understand the distributions of salt crusts and factors affecting them under field conditions. Samples of salt affected soils and associated salt crusts that represented a range of soil salinities, slope, and moisture contents were gathered from the banks of the Rio Grande. The samples were studied for salt identification by optical microscopy and using a high-resolution spectroradiometer, GER 3700, and for salinity level, and moisture content by the wet chemistry method. The study identified two main groups of salt crusts, contaminated halite and gypsum crusts. Reflectivity was correlated negatively with moisture content and positively with slope value, electrical conductivity and salt quantity. Reflectivity of halite-dominated crusts was higher than those of gypsum. Halite occurred over a greater range and higher slope values of soils than gypsum; however, a positive correlation between the slope and mean reflectivity of both salt crusts was reported. Although reflectivity of salt crusts varied according to changes in moisture content, and the salinity of the soil, moisture content can drastically reduce the reflection more effectively? than the other factors. The data reported indicate the possibility of assessing the type of salt crust by estimation of the ratio of slope and reflectivity to the other variables.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2019-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4154/GC.2019.01","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45642631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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