Bottom to top lithosphere structure and evolution of western Eger Rift (Central Europe)     

Vladislav Babuška  Jiří Fiala  Jaroslava Plomerová 《International Journal of Earth Sciences》2010,99(4):891-907

We present model of the structure and development of the entire lithosphere beneath the western Eger Rift (ER). Its crustal architecture and paths of volcanic products are closely related to sutures/boundaries of uppermost mantle domains distinguished by different orientations of olivine fabric, derived from 3-D analysis of seismic anisotropy. Three different fabrics of the mantle lithosphere belong to the Saxothuringian (ST), Teplá-Barrandian (TB) and Moldanubian (MD) microplates assembled during the Variscan orogeny. Dipping fossil (pre-assembly) olivine orientations, consistent within each unit, do not support any voluminous mantle delamination. The variable rift structure and morphology depend on the character of the pre-rift suture between the northern ST unit and the TB/MD units in the southern rift flank. The proper rift with typical graben morphology has developed above the steep lithosphere-scale suture between the ST and TB units. This subduction-related boundary originated from the closure of the ST Ocean. Parts of the crust and mantle lithosphere were dragged there into asthenospheric depths and then rapidly uplifted. The suture is marked by abrupt change in the mantle fabric and sharp gradients in regional gravity field and in metamorphic grade. The secular TB-side-down normal movement is reflected in deep sedimentary basins, which developed since the Carboniferous to Cenozoic and in topography. The graben morphology of the ER terminates above the “triple junction” of the ST, TB and MD mantle lithospheres. The junction is characterized by offsets of surface boundaries of the tectonic units from their mantle counterparts indicating a detachment of the rigid upper crust from the mantle lithosphere. The southwest continuation of the rift features in Bavaria is expressed in occurrences of Cenozoic sediments and volcanics above an inclined broad transition zone between the ST and MD lithospheres. Schematic scenario of evolution of the region consists mainly of a subduction of the ST lithosphere to depths around 140 km, exhumation of HP-HT rocks and the post-tectonic granitoid plutonism.  相似文献   

Cs¹³⁷ gamma-ray absorption in eclogites     

Vra Vaková  Vladislav Babuka 《Studia Geophysica et Geodaetica》1973,17(1):67

  相似文献   

Cs137 gamma-ray absorption in eclogites     

Věra Vaňková  Vladislav BabuŠka 《Studia Geophysica et Geodaetica》1973,17(1):67-67

  相似文献   

An apparatus for investigating the elastic anisotropy on spherical rock samples     

Zdeněk Pros  Vladislav Babuška 《Studia Geophysica et Geodaetica》1968,12(2):192-198

  相似文献   

ПРИБЛИЖЕННОЕ РЕЩЕНИЕ ВАРИАЦИОННОГО ТИПА ДЛЯ ОТОБРАЖЕНИЯ ГЕОГРАФИЧЕСКОЙ ТРАПЕЦИИ     

Vladislav Hojovec  Рецнзенм M. Pick 《Studia Geophysica et Geodaetica》1976,20(2):114-124

Zusammenfassung Die vorliegende Arbeit befasst sich mit der Methodik der approximativen Lösung des Variationstypes der Abbildung eines geographischen Trapezes nach dem Kriterium von Airy. Bei der Anwendung der Polynome nach dem Weierstrasschen Satze auf die Abbildungsgleichungen werden Koeffizienten gesucht, die das charakteristische Funktional minimalisieren. Wie es sich zeigt, kommt man zu einer approximativen Lösung bei der Anwendung von kubischen Polynomen und bei der Einführung der Symmetrie des abgebildeten geographischen Trapezes zum gegebenen mittleren Meridian. Als Kriterium für die erzielte Lösung wird der Wert des charakteristischen Funktionals sowie die Erfüllung natürlicher Randbedingungen benutzt. Die Methode wird als Beispiel auf das geographische Trapez angewandt, dessen Grenzen auf dem dreissigsten bis achzigsten geographischen Breitegrad liegen und die geographischen Längen einen Unterschied von 100° aufweisen. Es zeigt sich, dass bei der Benutzung der Zylinderprojektion des geographischen Trapezes das Variationskriterium von Airy durch die konforme (Mercatorsche) Abbildung exakt erfüllt ist. Bei der approximativen numerischen Lösung der Abbildung des gegebenen Trapezes resultiert bei der quadratischen Form der Abbildungsgleichungen ebenfalls die konforme Abbildung. M. Pick  相似文献   

Velocity anisotropy and symmetry of dunite fabric     

Vladislav Babuška  Jan Šílený  Reviewer K. Pěč 《Studia Geophysica et Geodaetica》1981,25(3):231-244

Summary From the space distribution of P- and S-wave velocities, determined at a hydrostatic pressure of 1 GPa, complete sets of elastic constants were calculated for the Twin Sisters dunite. It was found that orthorhombic symmetry is a reasonable approximation for the dunite sample; with one exception the deviations of the individual constants, determined from different waves, do not exceed a few percent. As a seismological application a simple model of a 120 km thick lithosphere, formed by the dunite, was considered for calculating the differences in the time arrivals of SV and SH waves. The greatest time differences, about 3s, were obtained in the vertical plane containing the direction of the greatest P-wave velocity, however, for the real lithosphere we estimate effects which only cause differences of the order of 1s.  相似文献   

Travel times of Friuli earthquakes propagating to the Bohemian Massif     

Jaroslava Plomerová  Libuše Ruprechtová  Vladislav Babuška  Reviewer A. Zátopek 《Studia Geophysica et Geodaetica》1979,23(3):288-295

17 mmu u uma uu 1976. anua 5 ¶rt;numu mauumu u¶rt;a mu u m na Pn, Pg, Sn u Sg. u¶rt; numm muam u mum ma¶rt;am¶rt;a ¶rt; uu mmu n¶rt;naam nu m m uamm aumm. ¶rt;am nu m mmu maua.  相似文献   

Elastic properties of garnet solid-solution series     

Vladislav Babuška  Jiří Fiala  Mineo Kumazawa  Ichiro Ohno  Yoshio Sumino 《Physics of the Earth and Planetary Interiors》1978,16(2):157-176

The elastic constants of sixteen garnet specimens of wide variety in chemical composition are accurately determined by means of the rectangular parallelpiped resonance method. The dependence of the elastic properties on chemical composition is analyzed using the present data and those for seven garnets investigated by other authors. The property X_i of a garnet solid solution i is given by a linear addition law in terms of the mole fraction n_ij of component j; X_i = Σn_ijX_j where the X_j's are the properties of the end-members j (j = pyrope, almandine, spessartine, grossular and andradite). The X_j's are determined for density ρ, bulk modulus K, and shear moduli C_s = (C₁₁ ? C₁₂)/2 and C₄₄. No systematic deviation is observed from the linear addition law for the elastic moduli nor for other quantities such as the elastic wave velocities. The extrapolated elastic moduli (Mbar) of the end-members are: