Japan Earthquake: An Exploratory View
Let’s first take a look at the yearly development of the earthquake activity overall:
The apparent increase in the last 10 years is striking – though I don’t have any explanation for this change, which is most probably not even man-made. Interestingly the magnitude (see next figure) does not increase, though the chance of stronger earthquakes will grow with the overall number.
The distribution of magnitudes (which is used for the coloring) is even more striking, looking at the earthquake in Japan, March 11th which is now rated as a 9.0.
The whole dataset contains only one earthquake at a higher magnitude, i.e., the earthquake originating the terrible tsunami on the 2nd Christmas day in 2004 at a magnitude of 9.1.
If we look at the coordinates of the measurements in longitudes and latitudes, we see how much the activity is concentrated on the tectonic hotspots.
We roughly see the shapes of some continents, with one exception. Africa seems to be free of any activity; probably due to the fact that it sits happily on its own tectonic plate.
Looking at this data, we can only start to understand the devastation Japan is facing.