Diese Seite ist aus Gründen der Barrierefreiheit optimiert für aktuelle Browser. Sollten Sie einen älteren Browser verwenden, kann es zu Einschränkungen der Darstellung und Benutzbarkeit der Website kommen!
Geophysics Homepage
Search:
Log in
print

Effects of Complicated 3D Rupture Geometries on Earthquake Ground Motion and Their Implications: A Numerical Study

Käser, Martin, and Frantisek Gallovic (2008), Effects of Complicated 3D Rupture Geometries on Earthquake Ground Motion and Their Implications: A Numerical Study, Geophys. J. Int., 172(1), 276-292, doi:10.1111/j.1365-246X.2007.03627.x.

Abstract
We present a numerical study of the effects of geometrically complicated 3D ruptures on near-source ground motions. In most of the kinematic and dynamic rupture modeling studies or seismic moment tensor and slip inversions the strong assumption of a perfectly
planar fault is made. However, it is known from geological field studies that real fault traces are not planar but characterized by relatively strong deflections, bends and other irregularities. In this paper we investigate the effects of such non-planar earthquake ruptures on ground motion modeling in comparison to their equivalent planar ones. For this purpose we apply the highly accurate Discontinuous Galerkin method that is capable of incorporating the geometry of complicated non-planar rupture surfaces by a set of double couple point sources that do not have to coincide with the mesh vertices. We generate a set of kinematic rupture models characterized by random spatial deflections with various correlation lengths and root mean square values. These deflections then determine the associated spatial strike and dip variations. We find that the deflected rupture models have the same seismic moment tensor as the perfectly planar one, however, with a reduced scalar moment, which we correct for. After a sound validation of our modeling approach, we present the effects of the deflections on synthetic velocity seismograms computed in the vicinity of the rupture. We observe that these geometrical irregularities do not just lead to high frequency effects but can strongly affect the synthetics in the whole frequency band. Finally, we discuss our observations in detail and conclude that the correct incorporation of the geometrical properties such as local strike and dip variations of the rupture surface is an important issue. We also discuss possible implications for some seismological fields, such as strong-motion simulations or seismic moment tensor and slip
inversions, where these results might have significant consequences.
BibTeX
@article{id920,
  author = {Martin K{\"a}ser and Frantisek Gallovic},
  journal = {Geophys. J. Int.},
  number = {1},
  pages = {276-292},
  title = {{Effects of Complicated 3D Rupture Geometries on Earthquake Ground Motion and Their Implications: A Numerical Study}},
  volume = {172},
  year = {2008},
  doi = {10.1111/j.1365-246X.2007.03627.x},
}
EndNote
%0 Journal Article
%A Käser, Martin
%A Gallovic, Frantisek
%D 2008
%N 1
%V 172
%J Geophys. J. Int.
%P 276-292
%T Effects of Complicated 3D Rupture Geometries on Earthquake Ground Motion and Their Implications: A Numerical Study
ImprintPrivacy PolicyContact
Printed 18. Aug 2019 07:05