The source time function of the great 1994 Bolivia deep earthquake is estimated from far-field seismograms by two techniques: time-domain inversion of direct P and S waveforms, and spectral-domain inversion of a combination of body waves, first-orbit traveling modes, and free oscillations. Both methods give consistent estimates, but the latter provides more bandwidth (1–300 mHz) and is more robust with respect to source-directivity effects and wave scattering. The earthquake released a total moment of 2.7 (±0.1) × 1021 Nm over an interval of about 50 s. Its history is highly episodic and can be divided into three stages: an initial sequence (0 ≲ t ≲ 13 s; 2 × 1020 Nm), a main-event sequence (13 ≲ t ≲ 38 s; 2.2 × 1021 Nm), and a terminal sequence (38 ≲ t ≲ 50 s; 3 × 1020 Nm). The main event is resolved into five subevents with peaks at ∼ 16, 20, 26, 29, and 36 s. The spatial pattern of moment release suggests that the main event was confined to the cold slab core, while the initial and terminal stages were part of a distinct westward-propagating rupture in the lower reaches of the former oceanic plate.
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