i have been thinking about the wave of this 11/11 seismic event. The wave has two distinct wave forms. The inner darker wave form appears to be rectangles rotated in a spiral. This seems to return to the Fourier Series perhaps applied in a Fibonacci Spiral.

What is it - not a normal natural wave?

1) It is either a man-made dual wave form

2) It is an other made octave shifting wave form