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Mind-Boggling Tsunami Video - Yazata - Oct 5, 2018

From the 2011 Tohoku earthquake and tsunami in Japan.

The video starts kind of slow with some earthquake footage and videos of relatively small waves, but ends with total apocalypse. Entire towns being erased from the Earth. Cities washed away.

There's a river upstream from a coastal city, a seemingly nice residential area, where people seem to have assumed they were safe and went down to the river to see what was happening. At first not much, what looks like a tidal bore, tossing small boats around. You see local police trying to get people to move people away. Then all hell breaks loose, the tsunami sirens cut loose and the river rises from its banks and floods the surrounding residential area. Then the river stops being a river entirely and turns into a monster, into a dark seething wave of rubble as the remains of buildings from the coastal city downstream are forced into the narrow channel upstream.

And to think that Japan got three hits in this one,

1. A huge (mag 8.9) earthquake. (Bad enough by any normal standard.)

2. A huge tsunami (largest in recorded Japanese history) that destroyed entire coastal cities.

3. And to top it all off, a wrecked nuclear power plant that melted down and created international consternation for months.

Too much... Sad

RE: Mind-Boggling Tsunami Video - C C - Oct 5, 2018

The surreal-like aerial view (starting circa the 14:40 mark) of it surging across flatland at or near Sendai is the one I most remembered from back then. I'd never seen a broadly sweeping, overhead view of a tsunami's crawling devastation like that before.

... Sendai was the nearest major city to the earthquake, 130 km (81 mi) from the epicenter ... The earthquake triggered powerful tsunami waves that reached heights of up to 40.5 metres (133 ft) in Miyako in Tōhoku's Iwate Prefecture, and which, in the Sendai area, traveled up to 10 km (6 miles) inland.

The earthquake moved Honshu (the main island of Japan) 2.4 m (8 ft) east, shifted the Earth on its axis by estimates of between 10 cm (4 in) and 25 cm (10 in), increased earth's rotational speed by 1.8 µs per day, and generated infrasound waves detected in perturbations of the low-orbiting GOCE satellite. Initially, the earthquake caused sinking of part of Honshu's Pacific coast by up to roughly a metre, but after about three years, the coast rose back and kept on rising to exceed its original height.  

... This megathrust earthquake was a recurrence of the mechanism of the earlier 869 Sanriku earthquake, which has been estimated as having a magnitude of at least 8.4 Mw, which also created a large tsunami that inundated the Sendai plain. Three tsunami deposits have been identified within the Holocene sequence of the plain, all formed within the last 3,000 years, suggesting an 800 to 1,100 year recurrence interval for large tsunamigenic earthquakes. In 2001 it was reckoned that there was a high likelihood of a large tsunami hitting the Sendai plain as more than 1,100 years had then elapsed. In 2007, the probability of an earthquake with a magnitude of Mw 8.1–8.3 was estimated as 99% within the following 30 years.


RE: Mind-Boggling Tsunami Video - Yazata - Oct 5, 2018

The thing that struck me were the people running around and on top of buildings.

There was the old man hobbling up the hill in one of the street views, who is cut off and clings to side of a building and almost certainly died.

There's the black minivan driving along that's engulfed by fast moving water. Its driver probably died too.

And at the end of the video there are the people fleeing on foot up a hill where people are filming cell-phone video, one woman stupidly carrying a large bag. And on the left there's what appears to be another woman further back pursued by an advancing wall of water and rubble moving faster than she was, who was probably engulfed and killed. (The camera doesn't show what happened to her, but I can guess.)