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The 2017 Tehuantepec earthquake (Mw8.2) was the first great normal fault event ever instrumentally recorded to occur in the Middle America Trench. The earthquake generated a tsunami with an amplitude of 1.8 m (height = 3.5 m) in Puerto Chiapas, Mexico. Tsunami waveforms recorded at coastal tide gauges and offshore buoy stations were used to estimate the optimum sea surface displacement without assuming any fault. Our optimum sea surface displacement model indicated that the maximum uplift of 0.5 m is located near the trench and the maximum subsidence of 0.8 m on the coastal side near the epicenter. We then estimated the fault slip distribution that can best explain the optimum sea surface displacement assuming 10 different fault geometries. The best model suggests that a compact region of large slip (3–6 m) extends from a depth of 30 km to 90 km, centered at a depth of 60 km. Tsunami waveforms resolve the optimum sea surface displacement with maximum sea surface uplift of 0.5 m and subsidence of 0.8 mLarge fault slip (3‐6 m) located at depths between 30 and 90 km is estimated from the optimum sea surface displacementLarge tsunami amplitudes up to 2.5 m due to edge waves are estimated inside and around a lagoon between Salina Cruz and Puerto Chiapas

The July 2015 Mw7.0 Solomon Islands tsunamigenic earthquake occurred ~40 km north of the February 2013 Mw8.0 Santa Cruz earthquake. The proximity of the two epicenters provided unique opportunities for a comparative study of their source mechanisms and tsunami generation. The 2013 earthquake was an interplate event having a thrust focal mechanism at a depth of 30 km while the 2015 event was a normal‐fault earthquake occurring at a shallow depth of 10 km in the overriding Pacific Plate. A combined use of tsunami and teleseismic data from the 2015 event revealed the north dipping fault plane and a rupture velocity of 3.6 km/s. Stress transfer analysis revealed that the 2015 earthquake occurred in a region with increased Coulomb stress following the 2013 earthquake. Spectral deconvolution, assuming the 2015 tsunami as empirical Green's function, indicated the source periods of the 2013 Santa Cruz tsunami as 10 and 22 min. Proximity of 2013 and 2015 events enabled spectral deconvolution of tsunami waveforms to estimate 2013 source periods of 10 and 22 minHigh rupture velocity of 3.6 km/s on north dipping normal‐fault plane for the 2015 Solomon Islands earthquakePositive stress transfer by the 2013 Santa Cruz earthquake to the 2015 Solomon Islands earthquake

We characterized tsunamis from the 29 March and 5 May 2015 Kokopo, Papua New Guinea, Mw7.5 earthquake doublet. Teleseismic body wave inversions using various rupture velocities (Vr) showed similar source‐time functions and waveform agreements, but the spatial distributions of the slips were different. The rupture durations were ~45 and ~55 s for the March and May events, with their peaks at ~25 and at ~17 s, respectively. Tsunami simulations favored source models with Vr= 1.75 and 1.50 km/s for the March and May earthquakes. The largest slip on the fault was similar (2.1 and 1.7 m), but the different depths and locations yielded maximum seafloor uplift of ~0.4 and ~0.2 m. Tsunami simulation from hypothetical great earthquakes (M8.4 and 8.5) on the New Britain trench showed that tsunami amplitudes may reach up to 10 m in Rabaul, but most tsunami energy was confined within the Solomon Sea. First instrumentally recorded tsunamis in the New Britain trenchSlow rupture velocities estimated from seismic and tsunami analysesDifferent tsunamis in earthquake doublet due to different location and depth