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
Log in

Study of Rotational Ground Motion in the Near-Field Region

Stupazzini, Marco, Josep de la Puente, Chiara Smerzini, Martin Käser, Heiner Igel, and Alberto Castellani (2009), Study of Rotational Ground Motion in the Near-Field Region, Bull. Seis. Soc. Am., 99(2B), 1271-1286, doi:10.1785/0120080153.

During the nineteenth and twentieth centuries observational seismologists
primarily recorded the earthquake-induced translational wave field, while the
rotational motion still remains poorly observed and investigated. We aim to further
understand the rotational ground motion and its relation to the translational wave field,
with a special emphasis on the near field few wavelengths away from the hypocenter
where damage related to rotational motion might need to be considered. A broad picture
of the available values of rotational amplitudes and their variability is obtained by
gathering most of the published data on strong rotational motion. To obtain a more
detailed picture we perform a large scale 3D numerical study of a strike-slip event in
the Grenoble valley where a combination of topographic, source, and site effects
produces a realistic wave field. We analyzed the synthetic dataset in terms of the rotational
and translational peak amplitudes and their dependence on two effects: nonlinear
soil behavior and source directivity. On soft soil deposit, we observe peak
ground rotation of 1 mrad and the peak ground rotation rate of 10 mrad=sec, for a
Mw 6.0 event. Those values show a strong dependence on the hypocenter location,
the local site conditions, and the topographical features, inducing a variability of almost
one order of magnitude in a range of distances of 20 km. Finally we compare our
numerical results in terms of peak ground velocity (PGV) versus peak ground rotation
(PGω) with field data obtained at similar scenarios (e.g., Parkfield) by array techniques
to investigate the relation between translational and rotational amplitudes expected in
the near field for shallow, medium-sized earthquakes. Results of our numerical simulation
fit reasonably well with those observed in past studies. Furthermore, the spatial
variations of PGV=PGω ratio show a trend, which is correlated with the velocity structure
of the model under study.
  author = {Marco Stupazzini and Josep  de la Puente and Chiara Smerzini and Martin K{\"a}ser and Heiner Igel and Alberto Castellani},
  journal = {Bull. Seis. Soc. Am.},
  number = {2B},
  pages = {1271-1286},
  title = {{Study of Rotational Ground Motion in the Near-Field Region}},
  volume = {99},
  year = {2009},
  doi = {10.1785/0120080153},
%0 Journal Article
%A Stupazzini, Marco
%A de la Puente, Josep 
%A Smerzini, Chiara
%A Käser, Martin
%A Igel, Heiner
%A Castellani, Alberto
%D 2009
%N 2B
%V 99
%J Bull. Seis. Soc. Am.
%P 1271-1286
%T Study of Rotational Ground Motion in the Near-Field Region
ImprintPrivacy PolicyContact
Printed 27. Nov 2021 09:59