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Károly Posgay Tamás Bodoky Zoltán Hajnal Tivadar M. Tóth Tamás Fancsik Endre Heged&#;s Attila Cs. Kovács Ern&#; Takács 《Geophysical Journal International》2006,167(1):187-203
The geologic origin of subhorizontal reflections, often observed in crustal seismic sections, was investigated by establishing metamorphic facies and strength of rocks in depth, and correlating these properties to seismic reflection sections from eastern Hungary. Estimation of the depths of metamorphic mineral stability zones utilized the principles developed by Fyfe et al. and known geothermal data of the area. The strength versus depth profile was derived by relating local seismic P -wave interval velocities to Meissner et al. 's activation energy. The results show that the series of subhorizontal reflections, observed in the Pannonian Basin, are a consequence of combined metamorphic and rheologic changes in depths. The synthesis of the integrated data set suggests that the retrograde alteration of the pre-Tertiary basement above the percolation threshold was made possible by the softening effect of shear zones and their water-conducting capacity. The subhorizontal reflections of highest energy, of the consolidated crust below the percolation threshold, originate in the depths of greenschist, amphibolite and granulite metamorphic mineral facies, which were formed in geothermal and pressure conditions similar to those existing today. These results imply the overprint of earlier (Variscan) metamorphic sequences of the crust by more recent retrograde metamorphic processes. 相似文献
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Zoltn Hajnal Endre Heged&#x;s G. Randy Keller Tams Fancsik Attila Cs. Kovcs Rbert Csabafi 《Tectonophysics》2004,388(1-4):239
A specially designed 700-km2 grid survey, deploying 1000 regularly distributed low-frequency seismic recording systems, successfully investigated one of the most complex geologic environments of the Pannonian basin. The wide-angle signals penetrated through over 1000 m of multi-phase igneous lithology and recognized, for the first time, the underlying enigmatic Permian to Early Triassic basement rocks. Tomographic inversion of the first arrival grid data resulted in determination of an accurate three-dimensional (3-D) velocity field, to a depth of 4 km. The anomalous changes of the spatial velocity data outline the regional extent of the Late Miocene magmatic intrusions, which are covered by over 2000 m of Mid-Miocene to Pleistocene clastics. Complex relationship was found between the surface potential data and the intrusive bodies. This multi-faceted geophysical data analysis established a functional technique for mapping a subsurface with intricate acoustic and structural complexity. 相似文献
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It is widely recognised that palaeobathymetry is a key control on the distribution of turbidite deposits. Thus, the utilisation of palaeobathymetric surfaces as an input for numerical turbidity current modelling offers a potentially powerful method to predict the distribution of deep marine sands in ancient (subsurface or outcrop) successions. Such an approach has been tested on an Aptian turbidite deposit from the Buchan Graben, UK Central North Sea, where modelled sand distributions could be quality controlled against available well data. 相似文献
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Christopher A.‐L. Jackson Gavin M. Elliott Elisabeth Royce‐Rogers Robert L. Gawthorpe Tor E. Aas 《Basin Research》2019,31(3):514-538
“Salt” giants are typically halite‐dominated, although they invariably contain other evaporite (e.g. anhydrite, bittern salts) and non‐evaporite (e.g. carbonate, clastic) rocks. Rheological differences between these rocks mean they impact or respond to rift‐related, upper crustal deformation in different ways. Our understanding of basin‐scale lithology variations in ancient salt giants, what controls this and how this impacts later rift‐related deformation, is poor, principally due to a lack of subsurface datasets of sufficiently regional extent. Here we use 2D seismic reflection and borehole data from offshore Norway to map compositional variations within the Zechstein Supergroup (ZSG) (Lopingian), relating this to the structural styles developed during Middle Jurassic‐to‐Early Cretaceous rifting. Based on the proportion of halite, we identify and map four intrasalt depositional zones (sensu Clark et al., Journal of the Geological Society, 1998, 155, 663) offshore Norway. We show that, at the basin margins, the ZSG is carbonate‐dominated, whereas towards the basin centre, it becomes increasingly halite‐dominated, a trend observed in the UK sector of the North Sea Basin and in other ancient salt giants. However, we also document abrupt, large magnitude compositional and thickness variations adjacent to large, intra‐basin normal faults; for example, thin, carbonate‐dominated successions occur on fault‐bounded footwall highs, whereas thick, halite‐dominated successions occur only a few kilometres away in adjacent depocentres. It is presently unclear if this variability reflects variations in syn‐depositional relief related to flooding of an underfilled presalt (Early Permian) rift or syn‐depositional (Lopingian) rift‐related faulting. Irrespective of the underlying controls, variations in salt composition and thickness influenced the Middle Jurassic‐to‐Early Cretaceous rift structural style, with diapirism characterising hangingwall basins where autochthonous salt was thick and halite‐rich and salt‐detached normal faulting occurring on the basin margins and on intra‐basin structural highs where the salt was too thin and/or halite‐poor to undergo diapirism. This variability is currently not captured by existing tectono‐stratigraphic models largely based on observations from salt‐free rifts and, we argue, mapping of suprasalt structural styles may provide insights into salt composition and thickness in areas where boreholes are lacking or seismic imaging is poor. 相似文献
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Endre Réthly 《Theoretical and Applied Climatology》1950,2(3):279-290
Zusammenfassung Einleitend werden verschiedene ungarische Arbeiten über den Zusammenhang zwischen Witterung und Krankheiten kritisch besprochen. Nach einer Übersicht über die verschiedenen Ansichten über die Abhängigkeit der Poliomyelitis von der Witterung wird eine 17jährige Statistik aus Ungarn über Witterungseinflüsse auf diese Krankheit untersucht. Es konnte kein Zusammenhang mit der Temperatur, mit dem Wechsel des Witterungscharakters und mit Fronten oder Abgleitflächen nachgewiesen werden. In den an Poliomyelitisfällen reichsten Jahren waren trockene Monate etwas häufiger. Es zeigen sich schwache Anzeichen für eine Doppelwelle während einer Sonnenfleckenperiode. Die Krankheit trat in den kühleren und niederschlagsreicheren nördlichen und nordöstlichen Teilen des Landes am häufigsten auf.
Summary At first divers Hungarian papers on the relations between weather and diseases are critically discussed. After giving a survey of the different opinions as to the influence of weather upon poliomyelitis, a 17 years statistics from Hungary is investigated in this respect. No connection could be found, however, neither with the temperature and the change of weather character nor with fronts or surfaces of subsidence. Most poliomyelitis cases occurred in years in which dry months were a little more frequent. There are slight indications of a double wave during a sunspot period. The disease was found to be most frequent in the northern and north-eastern regions being relatively cooler and richer in precipitation.
Résumé On examine tout d'abord différentes études hongroises concernant les relations entre le temps météorologique et les maladies. Après un aperçu sur les diverses opinions émises au sujet de la poliomyélite et de sa dépendance à l'égard du temps, on étudie sur le même sujet une statistique de 17 ans établie en Hongrie. On n'a pas pu prouver de relation avec la température, avec les changements de temps, ni avec les fronts ou les surfaces de subsidence. Les années les plus riches en poliomyélite ont eu un peu plus de mois secs. De faibles indices parlent en faveur d'une double période à l'intérieur de la période des taches solaires. La maladie a été la plus fréquente dans les parties nord et nord-est du pays qui sont aussi les plus froides et les plus humides.相似文献
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Fixed wavelength fluorescence (FF) for detection of polyaromatic hydrocarbon (PAH) metabolites in fish bile has been studied, and is presented through a laboratory and a field experiment. The method, which can be regarded as a biomarker of exposure to PAH, has proved to be a simple, rapid and cost effective method for monitoring PAH contamination. 相似文献
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The withdrawing Arctic ice edge will facilitate future sea transport and exploration activities in the area, which calls for the establishment of relevant cold water monitoring species. The present study presents first results of field baseline levels for core oil pollution biomarkers in Polar cod (Boreogadussaida) sampled from pristine, Arctic waters. Furthermore, biomarker response levels were characterized in controlled laboratory exposure experiments running over 2 weeks. Fish exposed to a simulated petrogenic spill (1 ppm dispersed, crude oil) exhibited elevated hepatic EROD activity, bile PAH-metabolites, and hepatic DNA-adducts, whereas male individuals exposed to simulated produced water (30 ppb nonylphenol) exhibited a strong induction of plasma vitellogenin. In conclusion, the results demonstrated low and robust biomarker baseline levels that were clearly different from exposure responses. In combination with its high abundance and circumpolar distribution, the Polar cod seems well qualified for oil pollution monitoring in Arctic waters. 相似文献
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Steinar Aas 《Polar research》2005,24(1-2):5-15
Seventy-seven years ago a tragedy took place in the Norwegian Arctic which shook the international community–especially Norwegians–and led to the public condemnation of the Italian explorer and airship builder Umberto Nobile. Steinar Aas, historian and author of a book on Nobile, has perused a trove of "new" material recently donated to the Norwegian Polar Institute and the Polar Museum in Tromsø, Norway. In this (unreviewed) piece, Aas explains why he finds the new collection a fascinating subject for further research. 相似文献