A large number of earthquakes have been modelled in detail using seismological, geological and LPq2+:JpS
geodetic information. Several common traits have been found for earthquakes kinematics at v-ThdE$G#
periods longer than 3s. At these frequencies, all large earthquakes (M>7) appear complex with EtGH\?d~]
highly variable slip, and propagate with rupture velocities close to about 80 % of the shear wave GSQfg
speed. Starting from these kinematic inversions, it is possible to use numerical wave propagation 6yN"
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models in order to estimate the complete radiated field including near and far field effects. q1UBKhpnH
Radiation can be separated into two main components: a near field term responsible for the socalled a
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fling steps due to permanent, geodetic offsets; and the far field that produces pulse like DWuRJ
motions. Using seismological scaling relations it is possible to explain the main features of 0[lS(K
displacement spectra using classical seismological models at long periods. Seismic simulations e:qo_eSC^-
may now be extended to the frequencies up to a few Hz by means of dynamic rupture propagation, u/} xE7G
where rupture is simulated starting from the kinematic models. In this talk I will review the main u-lrTa""z
results obtained so far and the new avenues of research that have been opened thanks to new near ,MRvuw0P
field earthquake data and the ability to simulate increasingly complex and realistic seismic 9^oo-,Su_
ruptures in a computer.