New information has been obtained by reanalyzing the rupture process of three large strike-slip earthquakes that occurred in the Gulf of Alaska on November 17 and 30, 1987 and March 6, 1988. We used spectral analysis of P-waves complemented with a simple technique for inverting body waves using a fixed source mechanism. Our results show that the Ms=7.0 event of November 17, which can be considered to be a foreshock to the November 30 event, consisted of two pulses of large seismic moment release: the first one with a duration of ~15 sec coincides with those obtained by other studies; the second, which occurs 20 sec after the first arrival is clearly visible on the records, but was not previously reported. The Ms=7.4 earthquake of November 30 is a complex event that ruptured on a fault plane trending north-south. The Ms=7.7 shock of March 6, 1988 was a simple event along the same north-south trend south of the November events. P-wave far field spectra exhibit an &ohgr;-1 intermediate trend between the usual &ohgr;0 and &ohgr;-2 slopes. This trend is due to rupture along a long, narrow fault, so the corner frequency associated with this intermediate trend is related to the reciprocal of rupture propagation time. We suggest that these events were due to a tear in the Pacific plate. ¿ American Geophysical Union 1995