Mark Buchanan, describes how some systems can be represented by the Power Law in his book 'Ubiquity - why catastrophes happen’:

In terms of energy, it turns out that the Gutenberg-Richter law boils down to one very simple rule: If earthquakes of type A release twice the energy of those of type B, then type A quakes happen four times less frequently. Double the energy, that is, and an earthquake becomes four times as rare. This simple pattern - a power law - holds for quakes over a tremendous range of energies.

Remarkably...

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