alt Hacker NewsI heard that smaller (relative) earthquakes actually lower the prob of larger ones, so maybe it is a good thing? A bunch of 7.X earthquakes in the ocean are not going to be hugely destructive.
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Almost all energy released in earthquakes is released in the biggest ones. No realistic number of smaller quakes is ever going to add up to even the single biggest earthquake ever recorded.
> A bunch of 7.X earthquakes in the ocean are not going to be hugely destructive.
New Zealand’s 5th most deadly disaster was Christchurch’s 6.2 which killed 185 people. It was a shallow aftershock from a larger, less destructive quake.
The damage was huge.
That's correct, if relatively small earthquakes would stop that could be the precursor to a much bigger one. It's like releasing tension gradually rather than all at once.
That is correct, but OTOH there was a 7.3 foreshock two days before the 2011 Tōhoku earthquake.
So the only thing we can say for sure is that it is still extremely difficult to predict earthquakes.
On the one hand earthquakes remove tension from the earth’s crust and release energy that can’t be used in future shocks.
On the other hand, if a shock doesn’t release all energy it may come to rest in a relatively weak spot that will soon give away again (https://en.wikipedia.org/wiki/Earthquake_swarm: “The Matsushiro swarm lasted from 1965 to 1967 and generated about 1 million earthquakes. This swarm had the peculiarity of being sited just under a seismological observatory installed in 1947 in a decommissioned military tunnel. It began in August 1965 with three earthquakes too weak to be felt, but three months later, a hundred earthquakes could be felt daily. On 17 April 1966, the observatory counted 6,780 earthquakes, with 585 of them having a magnitude great enough to be felt, which means that an earthquake could be felt, on average, every two and a half minutes.”)
Because of that, I think an earthquake will increase the probability of one occurring again soon, but decrease its strength.