Samoa Earthquake September 29, 2009, M 8.0 recorded at Keele
University, UK. This earthquake caused a tsunami which hit the
local islands causing at least 65 deaths in Samoa and at least
20 deaths in American Samoa according to the BBC. It is unusual
in that although it occurs close to the trench where the Pacific
Plate is subducted beneath the Australian Plate, the faulting
mechanism has been determined as being a normal fault rather
than a thrust. Note that as Keele is 15665km as the earthquake
travels from the epicentre the first arrival reaching Keele is
actually PP, rather than the direct P-wave which is intercepted
by the Earth’s core. The Keele seismic station is part of the UK
Seismology for Schools programme.