That is very odd. Im not an expert in this but the way i see it is we have a constant flow of energy on our planet. When energy builds up it needs a released. This is how we get storms and natural disaters, its the dispersment of built up energy. The dispersment of energy has its own pattern and flow it is not chaotic and unpredictable. It may appear that way to us but it is not. For all to go off at the same time is not a natural flow of energy. I guess the question here would be, what would cause all the energy build ups in these locations? What disruppted the current flow we had?

Edit: Second thought. Maybe it's not that odd. Maybe that way it's being reported makes it odd. I would have to find out more information so take my comment with a gain of salt.