排序方式: 共有16条查询结果,搜索用时 0 毫秒
1.
Károly Posgay Tamás Bodoky Zoltán Hajnal Tivadar M. Tóth Tamás Fancsik Endre Hegeds 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
2.
Zoltn Hajnal Endre Hegeds 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
3.
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
4.
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
5.
This paper presents a short theoretical summary of the series expansion-based 2.5D combined geoelectric weighted inversion (CGWI) method and highlights the advantageous way with which the number of unknowns can be decreased due to the simultaneous characteristic of this inversion. 2.5D CGWI is an approximate inversion method for the determination of 3D structures, which uses the joint 2D forward modeling of dip and strike direction data. In the inversion procedure, the Steiner’s most frequent value method is applied to the automatic separation of dip and strike direction data and outliers. The workflow of inversion and its practical application are presented in the study. For conventional vertical electrical sounding (VES) measurements, this method can determine the parameters of complex structures more accurately than the single inversion method. Field data show that the 2.5D CGWI which was developed can determine the optimal location for drilling an exploratory thermal water prospecting well. The novelty of this research is that the measured VES data in dip and strike direction are jointly inverted by the 2.5D CGWI method. 相似文献
6.
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
7.
Ákos Gyulai Mihály Dobróka Tamás Ormos Endre Turai Tibor Sasvári 《Acta Geophysica》2013,61(5):1184-1195
The methods of in-mine seam-sounding and transillumination (geoelectric tomography) for the detection of tectonic disturbances of coal seams were developed by the Department of Geophysics of the University of Miskolc in the 1970–80’s with the effective support of the former “Borsod” Coal Mines Ltd. The paper gives an overview about the theory of seam-sounding and a special geoelectric tomographic inversion, and introduces the in-mine geoelectric seam-sounding and transillumination measurement systems using vertical electrode dipoles. In the second part the paper, the results of an in-mine geoelectric measurement are presented, which was carried out in order to detect tectonic disturbances of the Miocene aged coal seams situated in Slovakia. As results of the geophysical investigation, the authors forecasted the tectonic features in the coal seam. The company confirmed the results by independent information about seam disturbances and tectonic features arising from the excavation of the investigated area. 相似文献
8.
Factor analysis of borehole logs for evaluating formation shaliness: a hydrogeophysical application for groundwater studies 总被引:1,自引:1,他引:0
The calculation of groundwater reserves in shaly sand aquifers requires a reliable estimation of effective porosity and permeability; the amount of shaliness as a related quantity can be determined from well log analysis. The conventionally used linear model, connecting the natural gamma-ray index to shale content, often gives only a rough estimate of shale volume. A non-linear model is suggested, which is derived from the factor analysis of well-logging data. An earlier study of hydrocarbon wells revealed an empirical relationship between the factor scores and shale volume, independent of the well site. Borehole logs from three groundwater wells drilled in the northeastern Great Hungarian Plain are analyzed to derive depth logs of factor variables, which are then correlated with shale volumes given from the method of Larionov. Shale volume logs derived by the statistical procedure are in close agreement with those derived from Larionov’s formula, which confirms the validity of the non-linear approximation. The statistical results are in good accordance with laboratory measurements made on core samples. Whereas conventional methods normally use a single well log as input, factor analysis processes all available logs to provide groundwater exploration with reliable estimations of shale volume. 相似文献
9.
Predicting soil erosion hazard in Lattakia Governorate(W Syria) 总被引:1,自引:0,他引:1
Mohammed Safwan Khallouf Alaa Alshiehabi Omran Bao Pham Quoc Thi Thuy Linh Nguyen Nam Thai Van Tran Anh Duong Harsányi Endre 《国际泥沙研究》2021,36(2):207-220
The main objective of this study is to predict soil erosion in the Lattakia Governorate(WSyria)using the Water Erosion Prediction Project model(WEPP)and to compare the result with that of the RUSLE.Field survey and data collection were carried out,and 44 soil samples were analyzed.In addition,all the necessary input files were prepared for use in the WEPP model and RUSLE.Results show that more than of 80%of the locations studied experience slight to moderate erosion(less than 5 t/ha/y),whereas the rest of the locations experience severe soil erosion hazard.Moreover,the volume of runoff estimated by the WEPP model is in the range of 51e321 mm,and the R^2 between the simulated soil erosion and the predicted runoff reached 0.68.Interestingly,the R^2 between the WEPP model and RUSLE is 0.56,which indicates a good correlation between the two models. 相似文献
10.
Long term effects of sublethal concentrations of oil on the marine environment have become of general concern. Cytochrome P4501A activity (EROD) in liver and fixed wavelength fluorescence detection of PAHs metabolites (FF) have in this study been used as biomarkers for dispersed oil exposure on a long term period of juvenile turbot (Scophthalmus maximus L.). A Continuous Flow System was used to carry out the study. The fish were continuously exposed to 0.125, 0.5 or 2.0 mg litre−1 dispersed topped crude oil for 6, 15, 24 h, 4 and 21 days followed by a 9 days recovery period in clean seawater. No induction of the cytochrome P4501A was measured. A maximum level in bile metabolites (4- to 5-fold) was recorded after 24 h of exposure revealing thereby a detoxification process, but a decline occurred from day 4 to day 21. This study demonstrated that FF detection of PAHs metabolites in bile could be a more sensitive biomarker than EROD activity in a long term exposure to sublethal concentration of oil. 相似文献