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As a component of the Flash Center’s validation program, we compare FLASH simulation results with experimental results from Los Alamos National Laboratory. The flow of interest involves the lateral interaction between a planar M a = 1.2 shock wave with a cylinder of gaseous sulfur hexafluoride (SF6) in air, and in particular the development of primary and secondary instabilities after the passage of the shock. While the overall evolution of the flow is comparable in the simulations and experiments, small-scale features are difficult to match. We focus on the sensitivity of numerical results to simulation parameters.  相似文献   
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Summary. Czechoslovak deep seismic reflection profiles across the West Carpathians, the first in the Alpine-Himalayan belt, and surface geological data, suggest that the passive margin of the Eurasian plate was obliquely overriden by the upper Carpatho-Pannonian plate during the end of the Krosno sea subduction some 17-14 Ma ago. The following period was dominated by slight oblique continental collision (transpression and transtension) of the West Carpathian-East Alpine continental material escaping from the East Alpine collision zone and Eurasian Brunovistulic passive margin. Crustal shortening in the North was accommodated by significant northerly dipping backthrusting and crustal thickening. Backthrusting is clearly observable on deep seismic lines 2T and 3T. Different subsidence features are present on the deep seismic line 3T. There are active pull-apart graben in the Vienna basin, mid-Miocene (16–10 Ma) low-angle normal faulting in the Danube basin, and there is a normal simple shear zone offsetting the Moho boundary beneath the Danube basin.  相似文献   
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We are proposing a hypothesis that earthquake swarms in the West Bohemia/Vogtland seismoactive region are generated by magmatic activity currently transported to the upper crustal layers. We assume that the injection of magma and/or related fluids and gases causes hydraulic fracturing which is manifested as an earthquake swarm at the surface. Our statements are supported by three spheres of evidence coming from the western part of the Bohemian Massif: characteristic manifestations of recent geodynamic activity, the information from the neighbouring KTB deep drilling project and from the 9HR seismic reflection profile, and the detailed analysis of local seismological data. (1) Recent manifestations of geodynamic activity include Quaternary volcanism, rich CO 2 emissions, anomalies of mantle-derived 3 He, mineral springs, moffets, etc. (2) The fluid injection experiment in the neighbouring KTB deep borehole at a depth of 9 km induced hundreds of micro-earthquakes. This indicates that the Earth's crust is near frictional failure in the western part of the Bohemian Massif and an addition of a small amount of energy to the tectonic stress is enough to induce an earthquake. Some pronounced reflections in the closely passing 9HR seismic reflection profile are interpreted as being caused by recent magmatic sills in the crust. (3) The local broadband seismological network WEBNET provides high quality data that enable precise localization of seismic events. The events of the January 1997 earthquake swarm are confined to an extremely narrow volume at depths of about 9 km. Their seismograms display pronounced reflections of P- and S-waves in the upper crust. The analysis of the process of faulting has disclosed a considerable variability of the source mechanism during the swarm. We conclude that the mechanism of intraplate earthquake swarms generated by magma intrusions is similar to that of induced seismicity. As the recent tectonic processes and manifestations of geodynamic activity are similar in European areas with repeated earthquake swarm occurrence (Bohemian Massif, French Massif Central, Rhine Graben), we assume that magma intrusions and related fluid and gas release at depths of about 10 km are the universal cause of intraplate earthquake swarm generation  相似文献   
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Summary Directionally independent average P residuals computed for waves of teleseismic events arriving under various azimuths and incidence angles provided the basis for estimating the lithosphere thickness beneath the Carpathians and their surroundings. A thin lithosphere (60–80 km) was determined for the Pannonian Basin and the Transylvanian Basin, the thickest lithosphere(about 180 km) beneath the South Carpathians at the contact with the Moesian Platform. In other parts of the Carpathian belt the lithosphere thickens beneath the outer parts towards the SW margin of the East-European and the Moldavian Platforms. The lithosphere thicknesses derived from P residuals correlate well with the magnetotelluric determinations of a layer of increased electrical conductivity in the upper mantle.
Резюме Осре?rt;ненные временные невязкu Р волн, незaвuсuмые оm нanрaвленuя u рaссчumaнные ?rt;ля у?rt;aленных землеmрясенuŭ uз волн, nрuхо?rt;ящuх nо?rt; рaзнымu aзuмуmaмu u у лaмu na?rt;енuя, ?rt;aюm основaнuе ?rt;ля оnре?rt;еленuя мощносmu лumосферы Кaрnam u uх окресmносmеŭ. Тонкaя лumосферa(60–80 км) оnре?rt;еленa ?rt;ля Пaннонско о u Трaнсuльвaнско о бaссеŭнов, a сaмaя мощнaя лumосферa(около 180 км) нaхо?rt;umся nо?rt; Южнымu Кaрnamaмu. В ?rt;ру uх чaсmях Кaрnamско о nоясa мощносmь лumосферы нaрaсmaеm во внешнuх зонaх в нanрaвленuu к ю о-зana?rt;ноŭ окрauне Восmочно-Евроnеŭскоŭ u Мол?rt;aвскоŭ nлamформ. Нaблю?rt;aеmся хорошaя корреляцuя мощносmu лumосферы, оnре?rt;еленноŭ нa основе невязок временu Р волн, с мa нumоmеллурuческuмu ?rt;aннымu nо лубuне слоя nовышенноŭ элекmроnрово?rt;uмосmu в верхнеŭ мaнmuu.
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