Research suggests extinct undersea volcanoes cause tsunami earthquakes
A new research has revealed that tsunami earthquakes may be caused by extinct undersea volcanoes squashed under Earth's crust.
While studying two extinct volcanoes off the coast of Poverty Bay and Tolaga Bay that have been squashed and sunk beneath the crust off the coast of New Zealand in a process called subduction, the researchers have suggested that the volcanoes provided a "sticking point" between a part of the Earth's crust called the Pacific plate, which was trying to slide underneath the New Zealand plate, causing the plates to "unstick" and the Pacific plate to move and the volcanoes to become subsumed under New Zealand.
The release of energy from both plates was unusually slow and close to the seabed, causing large movements of the sea floor, which led to the formation of very large tsunami waves.
The study, which may lead to improved detection measures, was published in the journal Earth and Planetary Science Letters.
(Posted on 28-06-2014)