March 6, 1895 Earthquake: W. Solomon Sea

1895, March 6, 6:35 p.m. [local time]. There was an earthquake at 9S, 150E, magnitude 7-8 (reference #99)

1895, March 6. An earthquake and tsunami struck the Trobriand Islands in March 1895 causing at least 30 deaths but until now the location and magnitude of the earthquake were quite uncertain. Our magnitude of 7.3±0.3 and location at (8.4°S, 150.1°E) compare well with Everingham's magnitude 7-8 and (9°S, 151°E)... There are few earthquakes located on the Trobriand Trench and this is the largest of them by far, and the only one known to have caused a destructive tsunami... The shaking in 1895 was not felt in Herbertshöhe (Kokopo near Rabaul) but was felt in Madang for example, and the tsunami was very localised, damaging just the Trobriand Islands and the east Papua Peninsula coast where three villages were destroyed, their occupants killed (annual report for British New Guinea tabled in the Australian Parliament)... The location must have been very local to the Trobriands as evidenced by the following observation at Sim-Sim (The Queenslander of 25 May 1895): "A little after sunset they experienced a shock, then followed a loud booming sound apparently not very far off, then another shock. After this there was a lull for a short time, and then they heard the noise of the advancing wave, which almost immediately afterwards swept over the flat." We surmise that this was the basis for Everingham's experienced assessment of the location. Another clue as to the location is that the wave struck the island of Sim-Sim on its western side so the focus was surely west of Sim-Sim, most probably within 50km of this location and perhaps less than 25km at (8.4S, 150.1E)... The seismological data favour an undivided Solomon Sea Plate. On this interpretation the Trobriand Trough is inactive and the 1895 earthquake would then have been an intraplate earthquake with, consequently, a longer return period than if it had been an interplate event. (reference #11522)