The event of 1969, known as the Horseshoe Fault earthquake and tsunami of 1969.
Fukao, 1973. The 28th February 1969 earthquake, with magnitude Mw= 7.3, had its epicentre in the same tsunamigenic area of the 1755 event and an estimated focal depth of 22 km. The focal mechanism was determined by several authors e.g. McKenzie (1972), Udias (1972), Fukao (1973); the fault plane solution for this event is a thrust, with a small strike slip component, N55ºE, parallel to Gorringe Ridge
Gjevik et al., 1997. The February 28, 1969, earthquake, with a surface wave magnitude of Mw=7.9, had an epicenter located at 36.01ºN, 10.57ºW on the Horseshoe Abyssal Plain, southeast of the Gorringe Bank. The estimated focal depth for this event is 22±6 km. [......] We have used source parameters determined by Fukao [1973], assuming the focal mechanism to be a pure thrust and neglecting the small left-lateral strike-slip component. Hence we have set dip angle = 52º, fault length = 80 km, fault width = 50 km, and a slip dislocation = 3 m.
