It wasnt really a tidal wave, its called a tsunami. Tidal waves refer to gravity, tidal patterns and weather systems (ie wind)
A tsunami occurs when an earthquake happens in the ocean and a ripple effect of the water takes place from the epicentre of the quake. From there the underwave shockwave travels relatively undetected due to the immense depth of the ocean. As the shockwave approaches a continental plate (ie land) the shockwaves have nowhere left to travel so they increase the water level dramatically resulting in massive coastal flooding of low lying coastal regions.
This quake on Dec 25th registered at 9.0 on the Richter scale, it had the power to physically move the island of Sumatra and increase the height of high tide in the Pacific Ocean by 10 cm....staggering power. 52 000 people have been confirmed dead so far, with 16 000 of them children and 27 000 in Indonesia alone.
I read that the quake actually stopped the rotation of the Earth briefly
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