TY  - JOUR
ID  - epos208
UR  - http://dx.doi.org/10.1111/j.1365-246X.2005.02585.x
IS  - 2
A1  - Vavrycuk, Vaclav
N2  - Focal mechanisms of seismic sources in anisotropic media are more complicated than in
isotropic media. Planar shear faulting produces pure double-couple (DC) mechanism in
isotropy, but generally non-double-couple (non-DC) mechanism in anisotropy. The non-DC
mechanism can comprise both the isotropic (ISO) and compensated linear vector dipole
(CLVD) components. The amount of the ISO and CLVD components depends on strength
and symmetry of anisotropy and on the orientation of faulting. Shear faulting in anisotropy
generates a pure DC mechanism, provided that faulting is situated in symmetry planes of or-
thorhombic or of higher anisotropy symmetries. The fault plane solution, i.e. the orientation
of the fault normal and the slip direction, can be retrieved from the seismic moment tensor
and from elastic parameters describing anisotropy at the source. Numerical modelling shows
that shear faulting in anisotropic rocks present in the Earth crust, the Earth mantle or in the
subduction zones can produce mostly mechanisms with the CLVD up to 30 per cent and with
the ISO up to 15 per cent. The fault plane solutions calculated under the assumption of isotropy
typically deviate from the true solutions by an angle of 5º to 10º.
VL  - 161
TI  - Focal mechanisms in anisotropic media
AV  - none
EP  - 346
Y1  - 2005/12/15/
PB  - Oxford University Press
JF  - Geophysical Journal International
KW  - anisotropy
KW  -  earthquake
KW  -  focal mechanism
KW  -  moment tensor
KW  -  shear faulting
SN  - 0956-540X
SP  - 334
ER  -