Facies patterns of the Upper Permian and Triassic formations within the Transdanubian Range are p... more Facies patterns of the Upper Permian and Triassic formations within the Transdanubian Range are presented. Based on surface and subsurface data, facies maps were compiled for six time slices which served as a basis of the paleogeographic reconstructions. Considering the entire Late Permian-Triassic interval, the Transdanubian Range unit shows a definite polarity: its northeastern part represents the seaward (internal) side, whereas its southwestern part represents the landward (external) side. A remarkable part of facies units of the Transdanubian Range could be correlated with time equivalent facies in the Southern Alps and the Upper Austroalpine nappes, providing an effective tool for the reconstruction of the original position of the displaced Transdanubian Range Unit.
In the Transdanubian Range (Hungary), a wide spectrum of Triassic dolomites is known. Mechanism o... more In the Transdanubian Range (Hungary), a wide spectrum of Triassic dolomites is known. Mechanism of dolomitization of the platform carbonate successions was subject of a number of studies but the study of dolomitization of basinal carbonates is very limited. Petrographical and isotope–geochemical characteristics of the Upper Triassic dolomitized carbonate deposits, formed in a fault-controlled intraplatform basin, and interpretation of the dolomite-forming processes are presented in the current paper. From the latest Carnian to Middle Norian under semi-arid climatic conditions density-driven flux of seawater derived mesohaline fluids was the dominant mechanism of the near-surface pervasive dolomitization of the thick platform carbonate succession. In the late Middle Norian incipient rifting of the Alpine Tethys led to establishment of an extensional structural regime and onset of the formation of the Kössen Basin. In the study area, above the dolomitized platform carbonate succession...
IYPE activities of various geo-science associations, universities, research institutes and privat... more IYPE activities of various geo-science associations, universities, research institutes and private companies in Hungary (www.foldev.hu) have been successfully coordinated by the Hungarian National Committee, which was established by the Hungarian Academy of Sciences, the UNESCO- and the IUGS National Committees. The National Launch Event (April 17, 2008) was followed with a four-days long "Earth Science Fair" at the Hungarian Natural History Museum in Budapest. The IYPE was even briefly reviewed in the Hungarian Parliament. The Science Festival, organized annually by the Hungarian Academy of Sciences, in 2008 had a special IYPE-inspired slogan: "Science for the Habitable Earth", where lectures were held about the modern content of the Greek Classical Elements ("earth", "water", "air" and "fire", that is energy) and about the Humanity. In 2008/2009 numerous publications (including the Hungarian version of the IYPE booklet series, under the title GEO-FIFIKA, the Természet Világa special issue in February 2009, the IYPE number of Földrajzi Közlemények (Geographical Communications), and the "Geological Map of Hungary for Tourists" were produced. Throughout the country, symposia (e.g. HUNGEO 2008, ELGI 100, MÁFI 140, Geotourism Symposium in October 2009), several contests (Hungarian Television "Delta", Élet és Tudomány on the occasion of the UN year, and the annual contests starting in 2007 at Miskolc University), film shows (e.g., the movie "Another Planet") and other performances (e.g. End of the Ice Age in Hungarian Natural History Museum) were organized, with modest but increasing media coverage. The worldwide premier of the Planet Earth TV took place in Hungary, on the occasion of the IAGA 11th Scientific Assembly (August 23-30, 2009, www.iaga2009sopron.hu). One of our conferences ("Earth and Heaven - Geology and Theology") pointed out that there should be no conflict between science and religion, either in the fields of Earth's history or evolution. Science (and only science) is able to give reliable knowledge how Nature works, and the investigation of the "ultimate Why" (i.e. the "Primordial Cause") should be left to religions and philosophy. At the same time, there are antagonistic conflicts between science and pseudo-science, and also between religions and pseudo-religions. Among the scientific programmes the activity of Geological Institute of Hungary in the OneGeology initiative should be at first mentioned. In 2007/2008, among the main environmental challenges, it was exclusively the so-called "global warming" in the focal point of public interest in Hungary. By now, the importance of soil, groundwater and energy have been also recognized, largely (or at least partly) due to IYPE. This is perhaps the largest result of the IYPE in Hungary.
ABSTRACT Dolomite most commonly forms via replacement of precursor carbonate minerals. For this r... more ABSTRACT Dolomite most commonly forms via replacement of precursor carbonate minerals. For this reason, diagnosing primarily precipitated organogenic dolomite in microbial mat deposits from the rock record is not straightforward, even though the deposits exhibit microbial fabric. Single and multiple dolomite crusts exhibiting microbial fabric occur in a pervasively dolomitized Middle Triassic platform succession. Two sections were studied in detail in the north-eastern part of the Transdanubian Range (north-central Hungary). In both sections, thin layer-couplets of two fabric types occur in the upper part of the metre-scale cycles. Microbial boundstone (fabric type 1)––characterised by clusters of dolomite microcrystals which display diagnostic microbial features, such as calcimicrobes, clotted–spherular aggregates and globules––composes the upper layer of couplets. The lower layer of the couplets is different in the two studied sections. In Section 1, it is micritic dolomite (fabric type 2) that is characterised by predominantly fine crystals and contains obscured microbial components. In Section 2, it is bioclastic dolomite (fabric type 3) that is rich in reworked dasycladalean fragments and consists of dolomite crystals of wide size-range from fine to coarse. The precipitation of the microcrystalline dolomite phase, which process is the focus of this study, is interpreted as being facilitated by mats and biofilms favouring/tolerating increasing frequency of subaerial conditions in the upper intertidal setting. Petrographic analyses revealed that organogenic calcite was also precipitated, especially in mat deposits rich in bioclasts. Synsedimentary dolomitization, resulting in fine crystals, was coupled with aragonite dissolution. Moreover, it postdated the organogenic precipitation and fibrous calcite cementation. Synsedimentary replacive dolomitization took place only in the peritidal caps of the shallowing-upward depositional units. Petrographic analyses provide circumstantial evidence constraining that microcrystalline dolomite did not form via mimetic replacement. Accordingly the microcrystalline dolomite, which shows microbial microfabrics in the studied samples, is interpreted as organogenic primary precipitate. Both peritidal processes, dolomite precipitation and replacement, were likely controlled by the environmental factors in a semi-arid climate. Those components of the platform succession that were not dolomitized in the peritidal environment were replaced and cemented by medium and coarsely crystalline dolomite during further burial at elevated temperature, as shown by fluid inclusion homogenisation temperature (62 to 83 °C) and negative stable oxygen isotope values. Thus, the majority of the studied formation consists of fabric-destructive dolomite (fabric type 4).
... Geologija, 31/32, pp. 415435, Ljubljana. 128 S. Kovács et al. Acta Geologica Hungarica 48, 2... more ... Geologija, 31/32, pp. 415435, Ljubljana. 128 S. Kovács et al. Acta Geologica Hungarica 48, 2005 Page 7. ... Poseb. izd. Geologija, 32, 172 p., Ljubljana. Pamic, J., V. Marci 1990: Petrologija amfibolitskih stijena slavonskih planina (sjev. Hrvatska). Geol. vjesn., 43, pp. ...
Facies patterns of the Upper Permian and Triassic formations within the Transdanubian Range are p... more Facies patterns of the Upper Permian and Triassic formations within the Transdanubian Range are presented. Based on surface and subsurface data, facies maps were compiled for six time slices which served as a basis of the paleogeographic reconstructions. Considering the entire Late Permian-Triassic interval, the Transdanubian Range unit shows a definite polarity: its northeastern part represents the seaward (internal) side, whereas its southwestern part represents the landward (external) side. A remarkable part of facies units of the Transdanubian Range could be correlated with time equivalent facies in the Southern Alps and the Upper Austroalpine nappes, providing an effective tool for the reconstruction of the original position of the displaced Transdanubian Range Unit.
In the Transdanubian Range (Hungary), a wide spectrum of Triassic dolomites is known. Mechanism o... more In the Transdanubian Range (Hungary), a wide spectrum of Triassic dolomites is known. Mechanism of dolomitization of the platform carbonate successions was subject of a number of studies but the study of dolomitization of basinal carbonates is very limited. Petrographical and isotope–geochemical characteristics of the Upper Triassic dolomitized carbonate deposits, formed in a fault-controlled intraplatform basin, and interpretation of the dolomite-forming processes are presented in the current paper. From the latest Carnian to Middle Norian under semi-arid climatic conditions density-driven flux of seawater derived mesohaline fluids was the dominant mechanism of the near-surface pervasive dolomitization of the thick platform carbonate succession. In the late Middle Norian incipient rifting of the Alpine Tethys led to establishment of an extensional structural regime and onset of the formation of the Kössen Basin. In the study area, above the dolomitized platform carbonate succession...
IYPE activities of various geo-science associations, universities, research institutes and privat... more IYPE activities of various geo-science associations, universities, research institutes and private companies in Hungary (www.foldev.hu) have been successfully coordinated by the Hungarian National Committee, which was established by the Hungarian Academy of Sciences, the UNESCO- and the IUGS National Committees. The National Launch Event (April 17, 2008) was followed with a four-days long "Earth Science Fair" at the Hungarian Natural History Museum in Budapest. The IYPE was even briefly reviewed in the Hungarian Parliament. The Science Festival, organized annually by the Hungarian Academy of Sciences, in 2008 had a special IYPE-inspired slogan: "Science for the Habitable Earth", where lectures were held about the modern content of the Greek Classical Elements ("earth", "water", "air" and "fire", that is energy) and about the Humanity. In 2008/2009 numerous publications (including the Hungarian version of the IYPE booklet series, under the title GEO-FIFIKA, the Természet Világa special issue in February 2009, the IYPE number of Földrajzi Közlemények (Geographical Communications), and the "Geological Map of Hungary for Tourists" were produced. Throughout the country, symposia (e.g. HUNGEO 2008, ELGI 100, MÁFI 140, Geotourism Symposium in October 2009), several contests (Hungarian Television "Delta", Élet és Tudomány on the occasion of the UN year, and the annual contests starting in 2007 at Miskolc University), film shows (e.g., the movie "Another Planet") and other performances (e.g. End of the Ice Age in Hungarian Natural History Museum) were organized, with modest but increasing media coverage. The worldwide premier of the Planet Earth TV took place in Hungary, on the occasion of the IAGA 11th Scientific Assembly (August 23-30, 2009, www.iaga2009sopron.hu). One of our conferences ("Earth and Heaven - Geology and Theology") pointed out that there should be no conflict between science and religion, either in the fields of Earth's history or evolution. Science (and only science) is able to give reliable knowledge how Nature works, and the investigation of the "ultimate Why" (i.e. the "Primordial Cause") should be left to religions and philosophy. At the same time, there are antagonistic conflicts between science and pseudo-science, and also between religions and pseudo-religions. Among the scientific programmes the activity of Geological Institute of Hungary in the OneGeology initiative should be at first mentioned. In 2007/2008, among the main environmental challenges, it was exclusively the so-called "global warming" in the focal point of public interest in Hungary. By now, the importance of soil, groundwater and energy have been also recognized, largely (or at least partly) due to IYPE. This is perhaps the largest result of the IYPE in Hungary.
ABSTRACT Dolomite most commonly forms via replacement of precursor carbonate minerals. For this r... more ABSTRACT Dolomite most commonly forms via replacement of precursor carbonate minerals. For this reason, diagnosing primarily precipitated organogenic dolomite in microbial mat deposits from the rock record is not straightforward, even though the deposits exhibit microbial fabric. Single and multiple dolomite crusts exhibiting microbial fabric occur in a pervasively dolomitized Middle Triassic platform succession. Two sections were studied in detail in the north-eastern part of the Transdanubian Range (north-central Hungary). In both sections, thin layer-couplets of two fabric types occur in the upper part of the metre-scale cycles. Microbial boundstone (fabric type 1)––characterised by clusters of dolomite microcrystals which display diagnostic microbial features, such as calcimicrobes, clotted–spherular aggregates and globules––composes the upper layer of couplets. The lower layer of the couplets is different in the two studied sections. In Section 1, it is micritic dolomite (fabric type 2) that is characterised by predominantly fine crystals and contains obscured microbial components. In Section 2, it is bioclastic dolomite (fabric type 3) that is rich in reworked dasycladalean fragments and consists of dolomite crystals of wide size-range from fine to coarse. The precipitation of the microcrystalline dolomite phase, which process is the focus of this study, is interpreted as being facilitated by mats and biofilms favouring/tolerating increasing frequency of subaerial conditions in the upper intertidal setting. Petrographic analyses revealed that organogenic calcite was also precipitated, especially in mat deposits rich in bioclasts. Synsedimentary dolomitization, resulting in fine crystals, was coupled with aragonite dissolution. Moreover, it postdated the organogenic precipitation and fibrous calcite cementation. Synsedimentary replacive dolomitization took place only in the peritidal caps of the shallowing-upward depositional units. Petrographic analyses provide circumstantial evidence constraining that microcrystalline dolomite did not form via mimetic replacement. Accordingly the microcrystalline dolomite, which shows microbial microfabrics in the studied samples, is interpreted as organogenic primary precipitate. Both peritidal processes, dolomite precipitation and replacement, were likely controlled by the environmental factors in a semi-arid climate. Those components of the platform succession that were not dolomitized in the peritidal environment were replaced and cemented by medium and coarsely crystalline dolomite during further burial at elevated temperature, as shown by fluid inclusion homogenisation temperature (62 to 83 °C) and negative stable oxygen isotope values. Thus, the majority of the studied formation consists of fabric-destructive dolomite (fabric type 4).
... Geologija, 31/32, pp. 415435, Ljubljana. 128 S. Kovács et al. Acta Geologica Hungarica 48, 2... more ... Geologija, 31/32, pp. 415435, Ljubljana. 128 S. Kovács et al. Acta Geologica Hungarica 48, 2005 Page 7. ... Poseb. izd. Geologija, 32, 172 p., Ljubljana. Pamic, J., V. Marci 1990: Petrologija amfibolitskih stijena slavonskih planina (sjev. Hrvatska). Geol. vjesn., 43, pp. ...
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