Geologia Croatica最新文献

{"title":"Chemical, mineralogical and structural features of native and expanded perlite from Macedonia","authors":"Arianit A. Reka, B. Pavlovski, K. Lisichkov, Ahmed Jashari, B. Boev, I. Boev, M. Lazarova, V. Eskizeybek, A. Oral, G. Jovanovski, P. Makreski","doi":"10.4154/gc.2019.18","DOIUrl":"https://doi.org/10.4154/gc.2019.18","url":null,"abstract":"The physico-mechanical, chemical and mineralogical characteristics of volcanic glass (perlite) from the Mariovo region (Macedonia) as well as the mineralogical changes that occur during its thermal treatment were investigated to demonstrate its utilization for industrial use. The native perlite was characterized by chemical analysis, X-ray powder diffraction (XRPD), infrared (IR) spectroscopy, thermal analysis (TGA/DTA), scanning electron microscopy (SEM-EDX), transmission electron microscopy (TEM), and solid- state NMR. The chemical examination suggests that the perlite represents an acidic volcanic rock with a high percentage of SiO2 (72.45%), high in alkali metal oxides (4.21 wt.% K2O, 3.56 wt.% Na2O), with a loss of ignition 3.54 wt.%. Results from the XRPD indicated major amorphous behaviour, with low amounts of feldspars, quartz, and cristobalite. SEM examinations revealed glassy structure with presence of certain pores (dimensions ranging from 50–100 μm). The determined expansion coefficient was 20 times its original volume. XRPD of expanded perlite compared to the native perlite depicted new intensive peaks of cristobalite. SEM and TEM revealed irregular morphology with broken or ragged edges. On the basis of the chemical and mineralogical composition, the studied perlite is classified as an appropriate material suitable as ceramic flux to lower the sintering temperature.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4154/gc.2019.18","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45297760","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}

{"title":"Northern Velebit (Croatia) karst hydrological system: results of a preliminary 2H and 18O stable isotope study","authors":"D. Paar, D. Mance, A. Stroj, M. Pavić","doi":"10.4154/GC.2019.15","DOIUrl":"https://doi.org/10.4154/GC.2019.15","url":null,"abstract":"Researching the hydrogeological properties of karst systems is very challenging due to their ex- treme heterogeneity. A grey-box approach in karst res","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48592018","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}

{"title":"Revision of the genus Cordaites UNGER from the Permian of the Intrasudetic Basin (Broumov Formation, Olivětín Member, Czech Republic)","authors":"Z. Šimůnek","doi":"10.4154/gc.2019.16","DOIUrl":"https://doi.org/10.4154/gc.2019.16","url":null,"abstract":"Cordaitalean remains are not very common in the Permian of the Intrasudetic Basin (Czech Republic and Poland) and have usually been classified simply as Cordaites sp. Based on leaf morphology, venation and cuticles (where possible), five cordaitalean species are recognised: Cordaites cf. beinertianus, C. cf. affinis, C. cf. roesslerianus, C. cf. foliolatus and Cordaites sp. A. The determination of Cordaites leaves is difficult because of the variability and similarities between several species. The biggest leaf was determined as Cordaites cf. beinertianus. The cuticles of Cordaites cf. affinis resemble the cuticles of C. palmaeformis and C. radvanicensis,however, the latter is known only in a fragmentary state. Cordaites beinertianus and C. palmaeformis are very similar and are considered as conspecific by some authors. Cordaites affinis has generally smaller leaves. Cordaites cf. roesslerianus is comparable with C. principalis with which it is sometimes synonymised. C. cf. foliolatus is represented by a much narrower leaf than is typical for cordaitalean leaves from France. Cordaites sp. A is a relatively small leaf-form and differs from all other forms previously described.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46222520","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}

{"title":"On the origin of both a recent and submerged tombolo on Prvić Island in the Kvarner area (Adriatic Sea, Croatia)","authors":"Č. Benac, N. Bočić, I. Ružić","doi":"10.4154/gc.2019.14","DOIUrl":"https://doi.org/10.4154/gc.2019.14","url":null,"abstract":"This paper analyzes the origins of two tombolos (one recent and another fossil/submerged) on the southwestern coast of Prvic Island, which is located in the Kvarner area in the northeastern part of the Adriatic Sea. \u0000A recent tombolo on Cape Pipa was formed by the erosion of Quaternary deposits and Palaeogene siliciclastic rocks. The submerged tombolo is much bigger, clearly visible on the sea bed toward the southwest. The conditions for forming a submerged and recent tombolo have occurred during a slow rise and then stagnation of sea level of the Adriatic Sea in the Holocene. The sea  flooded the fossil tombolo probably in the final part of a period of rapid sea-level rise at the beginning of the Holocene when a large proportion of the Quaternary sediments were eroded. Waves from the northwest (tramuntana) and southeast (jugo) refract and diffract around the tombolo. The nourishment of the beach body happens permanently on both sides of the cape. Accumulated sediments are protected by resistant rocky blocks of breccia on the peak of Cape Pipa, acting as a natural tombolo. Due to the fact that wave directions are perpendicular to the beach coastline, they do not generate longshore currents that would erode sediment in beach bodies around Cape Pipa. Therefore, the recent tombolo is probably stable in the present climatic and oceanographic conditions in the Kvarner area.","PeriodicalId":55108,"journal":{"name":"Geologia Croatica","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44753082","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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}

{"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":null,"pages":null},"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}