ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Monograph available for loan
    Monograph available for loan
    Ray method in seismology (1977)
    Praha : Univ. Karlova
    Details Availability
    Call number: 10847 ; 14618
    Type of Medium: Monograph available for loan
    Pages: 214 S. : graph. Darst.
    Location: Upper compact magazine
    Location: Upper compact magazine
    Branch Library: GFZ Library
    Branch Library: GFZ Library
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    BOOK
    Link to Library Catalog
    get availability status
  • 2
    Unknown
    Seismic Waves in Laterally Inhomogeneous Media, Part I (1996)
    Basel, Boston, Berlin : Birkhäuser
    Details
    Keywords: seismic waves ; geophysics ; seismology
    Description / Table of Contents: The special issue contains contributions presented at the international workshop Seismic waves in laterally inhomo- geneous media IV, which was held at the Castle of Trest, Czech Republic, May 22-27, 1995. The workshop, which was attended by about 100 seismologists from more than 10 countries, was devoted mainly to the current state of theoretical and computational means of study of seismic wave propagation in complex structures. The special issue can be of interest for theoretical, global and explorational seismologists. The first part contains papers dealing with the study and the use of various methods of solving forward and inverse problems in complicated structures. Among other methods, discrete-wave number method, the finite-difference method, the edge-wave supperposition method and the ray method are studied and used. Most papers contained in the second part are related to the ray method. The most important topics are two-point ray tracing, grid calculations of travel times and amplitudes and seismic wave propagation in anisotropic media.
    Pages: Online-Ressource (342 Seiten) , Illustrationen, Diagramme, Karten
    ISBN: 9783764356484
    URL: https://link.springer.com/journal/24/148/1/
    Language: English
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    E-BOOK
  • 3
    Unknown
    Seismic Waves in Laterally Inhomogeneous Media (2002)
    Basel, Boston, Berlin : Birkhäuser
    Details
    Keywords: seismic waves ; geophysics ; seismology
    Description / Table of Contents: This special issue contains contributions presented at the international workshop Seismic Waves in Laterally Inhomogeneous Media V, which was held at the Castle of Zahrádky, Czech Republic, June 5 - 9, 2000. The workshop, which was attended by about 60 seismologists from 16 countries, was devoted mainly to the current state of theoretical and computational means of study of seismic wave propagation in complex structures. The special issue begins with papers dealing with the study and the application of the ray methods. Problems such as coupling of quasi-shear waves or smoothing of models for effective ray computations are dealt with. Applications of the ray methods in seismic exploration are presented. Further, directional wavefield decomposition, phase space, path integral and parabolic equation methods are discussed. Attention is also devoted to attenuation and scattering problems, and to seismic inversion problems.
    Pages: Online-Ressource (VI, 503 Seiten)
    ISBN: 9783764366773
    URL: http://link.springer.com/journal/24/159/7/
    Language: English
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    E-BOOK
  • 4
    Unknown
    Seismic Waves in Laterally Inhomogeneous Media, Part II (1996)
    Basel, Boston, Berlin : Birkhäuser
    Details
    Keywords: seismic waves ; geophysics ; seismology
    Description / Table of Contents: The special issue contains contributions presented at the international workshop Seismic waves in laterally inhomogeneous media IV, which was held at the Castle of Trest, Czech Republic, May 22-27, 1995. The workshop, which was attended by about 100 seismologists from more than 10 countries, was devoted mainly to the current state of theoretical and computational means of study of seismic wave propagation in complex structures. The special issue can be of interest for theoretical, global and explorational seismologists. The first part contains papers dealing with the study and the use of various methods of solving forward and inverse problems in complicated structures. Among other methods, discrete-wave number method, the finite-difference method, the edge-wave supperposition method and the ray method are studied and used. Most papers contained in the second part are related to the ray method. The most important topics are two-point ray tracing, grid calculations of travel times and amplitudes and seismic wave propagation in anisotropic media.
    Pages: Online-Ressource (372 Seiten)
    ISBN: 9783034890496
    URL: http://link.springer.com/journal/24/148/3/
    Language: English
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    E-BOOK
  • 5
    Electronic Resource
    Electronic Resource
    Preface (1996)
    Springer
    Pure and applied geophysics 148 (1996), S. 343-343 
    Details
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00874571
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Preface (1996)
    Springer
    Pure and applied geophysics 148 (1996), S. 1-1 
    Details
    ISSN: 1420-9136
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00882051
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Computation of additional components of the first-order ray approximation in isotropic media (1996)
    Springer
    Pure and applied geophysics 148 (1996), S. 227-253 
    Details
    ISSN: 1420-9136
    Keywords: Ray series ; first-order additional terms ; Green function
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract This study shows that the use of the first-order additional components of the ray method in the seismic wave field modeling is easy and that it can bring a substantial improvement of the standard ray results obtained with the zero-order ray approximation only. For the calculation of a first-order additional component, spatial derivatives of the parameters of the medium and spatial derivatives of the zero-order ray amplitude term are necessary. The evaluation of the former derivatives is straightforward; the latter derivatives can be calculated approximately from neighboring rays by substituting the derivatives by finite differences. This allows an effective calculation of the first-order additional terms in arbitrary laterally varying layered media. The importance of the first-order additional terms is demonstrated by the study of individual higher-order terms of the ray series representing elementaryP andS elastodynamic Green functions for a homogeneous isotropic medium. The study shows clearly that the consideration of the first-order additional terms leads to a more substantial decrease of the difference between approximate and exact elementary Green functions than any other higher-order term. With this in mind, effects of the first-order additional terms on the ray synthetic seismograms for aVSP configuration are studied. It is shown that the use of the additional terms leads to such phenomena, unknown in the zero-order approximation of the ray method, like quasi-elliptical and transverse polarization of a singleP wave or longitudinal polarization of a singleS wave.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00882061
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Point source radiation in inhomogeneous anisotropic structures (1996)
    Springer
    Pure and applied geophysics 148 (1996), S. 591-623 
    Details
    ISSN: 1420-9136
    Keywords: Inhomogeneous anisotropic media ; point sources ; the ray Green function ; the directivity function ; the radiation pattern ; ray synthetic seismograms
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The ray formulae for the radiation from point sources in unbounded inhomogeneous isotropic as well as anisotropic media consist of two factors. The first one depends fully on the type and orientation of the source and on the parameters of the medium at the source. We call this factor the directivity function. The second factor depends on the parameters of the medium surrounding the source and this factor is the well-known geometrical spreading. The displacement vector and the radiation pattern defined as a modulus of the amplitude of the displacement vector measured on a unit sphere around the source are both proportional to the ratio of the directivity function and the geometrical spreading. For several reasons it is desirable to separate the two mentioned factors. For example, there are methods in exploration seismics, which separate the effects of the geometrical spreading from the observed wave field (so-called true amplitude concept) and thus require the proposed separation. The separation also has an important impact on computer time savings in modeling seismic wave fields generated by point sources by the ray method. For a given position in a given model, it is sufficient to calculate the geometrical spreading only once. A multitude of various types of point sources with a different orientation can then be calculated at negligible additional cost. In numerical examples we show the effects of anisotropy on the geometrical spreading, the directivity and the radiation pattern. Ray synthetic seismograms due to a point source positioned in an anisotropic medium are also presented and compared with seismograms for an isotropic medium.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00874581
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Kinematic inversion for qP- and qS-waves in inhomogeneous hexagonally symmetric structures (1992)
    Oxford, UK : Blackwell Publishing Ltd
    Geophysical journal international 108 (1992), S. 0 
    Details
    ISSN: 1365-246X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: We propose a kinematic inversion technique based on the first-order perturbation method for anisotropic media. In contrast to previous techniques, this one can be used to invert traveltimes of quasi-compressional as well as split quasi-shear waves, even if the initial unperturbed medium is isotropic. In principle, the technique is applicable to general 3-D laterally inhomogeneous anisotropic structures with an arbitrary degree of anisotropy. Here, however, for simplicity, media with hexagonal symmetry are considered. The effectiveness and limitations of the inversion technique are illustrated with synthetic VSP traveltime data. A simple linear variation of elastic parameters with depth is considered. The inversion scheme is tested both on data with pronounced shear wave splitting and data in which the shear wave splitting is negligible, the limiting case being data generated for a vertically inhomogeneous isotropic structure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-246X.1992.tb04639.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Perturbation from isotropic to anisotropic heterogeneous media in the ray approximation (1991)
    Oxford, UK : Blackwell Publishing Ltd
    Geophysical journal international 106 (1991), S. 0 
    Details
    ISSN: 1365-246X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences
    Notes: In this paper, perturbation methods are used to obtain ray results in slightly anisotropic, heterogeneous media from a nearby isotropic medium. The advantage of this approach is that rays computed by available 2-D isotropic ray-tracing algorithms can be used to approximately compute, by perturbation, ray theoretical results in more general 3-D slightly anisotropic, heterogeneous media. The perturbation approach also makes possible an efficient computation of ray sensitivity operators necessary in seismic tomography studies. In order to compute approximate ray results for quasi-shear waves, degenerate perturbation theory must be used in order to split a single shear wave in an isotropic medium into two quasi-shear waves in a nearby anisotropic medium. The perturbation approach is tested on an effectively anisotropic model of aligned cracks within a linear, vertical velocity gradient. Perturbed traveltimes, ray paths and particle motions of quasi-compressional and quasi-shear waves for such an anisotropic medium are compared with exact ray results. Good agreement between the exact and perturbed results is found.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-246X.1991.tb04597.x
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...