Abstract. We investigate the spatio-temporal complexity of than a few tens of cm at various sites in the Pacific, the Marmoment release of the February 21, 1996 Peru earthquake quesas experienced locally water waves on the order of 2 m (M w 7.5). We use a non-linear source tomographic technique, [Heinrich et al., 1998]. We investigate the source process of based on simulated annealing, to invert surface wave source the 1996 Peru earthquake using two different methods: a) spectra for the slip distribution on a gently dipping fault plane. source tomography based on surface wave data that provide us The spectra (5-65 mHz) are obtained using an empirical with an appropriate low-frequency resolution of the source Green's function (EGF) method applied to first and second or-process (5-65 mHz), and an enhanced sensitivity to source dibit fundamental mode Rayleigh waves. Spectra are well fit by rectivity effects; b) inversion of broadband body waves to exa 110 km bilateral rupture, subparallel to the trench, updip of tend our analysis to higher frequencies (10-500 mHz). Our the hypocenter, with a total moment of 2.0x102ø Nm. The source tomographic model serves as a basis to calculate the non-linear inversion reveals a 30x30 km 2 major slip patch south the onset, where rupture velocities attain 1.5-2.0 km/s. Inversions of teleseismic broadband P and SH waves (10-500 mHz) indicate little or no directivity, consistent with the surface wave data. The average source time functions for both the surface and body wave data are similar in shape and in duration (-50 s). Part of the slip during the 1996 Peru event occurred in a region of reduced background seismicity, as was the case for the 1992 Nicaragua slow event, suggesting that the seismogenic potential of low seismicity regions near the trench should be globally reassessed.

Abstract. The February 1996 Peruvian earthquake generated a larger tsunami than expected from its surface magnitude. This discrepancy as well as the long rupture duration indicate that this event is a 'tsunami earthquake'. The associated tsunami was strong locally with runup heights of 1 to 5 meters along a coastline of 400 km. It is shown that this tsunami can be modeled for a seismic moment of 2.102ø Nm, using a rigidity of 2.10 •ø N/m 2. The tsunami propagation is modeled solv-

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