Are we overdue?

From time to time, someone will remark to me that Tokyo is "overdue" for a major earthquake.  No matter how many times I hear this, I find it odd and a little illogical.  It suggests that there was a "due date" for a major earthquake and now that this "due date" has passed, we are all living on borrowed time.  I think it's quite obvious that there is no "due date" for a major earthquake anywhere and hence the idea that we are "overdue" is as about as logical as other popular forecasts of doom, such as "we're overdue for another ice age!" and "the Earth is overdue to be struck by a gigantic asteroid!"  No fear.

It is generally accepted that earthquake predictions is incredibly imprecise and little more than guesswork. However, one thing which is accepted is what causes earthquakes at tectonic boundaries.  In short, tectonic plates slide past each other at their boundaries.  The boundaries of tectonic plates may be rough causing the plates to stick from time to time.  If the plates stick, pressure will build up.  If a large amount of pressure builds up and this pressure is released suddenly, there will be an earthquake.  The reasons why people cannot predict earthquakes are as follows.

1. No-one knows if there is a large build-up of pressure at the boundary of any particular tectonic plate.  There may be none. The fact that plates move about does not necessarily mean that there is any pressure build-up.

2. If there was a large build-up of pressure, no-one knows whether this pressure will be released suddenly or not.  There is no reason why it must be.

3. If there was a large build-up of pressure and it was released suddenly (neither of which we know), no-one knows the specific place where the pressure will be released.

Considering the above, there is no reason why a major earthquake must strike Tokyo ever again.  Similarly, there is no reason why a major asteroid must strike the Earth again.  Of course, it may well happen but so could many things.

People often remark that a major earth quake has not struck the Tokyo area since September 1923.  That establishes nothing other than the fact that a major earth quake has not occurred for close to 90 years.  Earth quakes are not like Haley’s Comet (i.e. guaranteed to occur every so many decades).

Over the last year, there seems to have been pessimistic forecasts in many areas: stock markets, debt markets, employment markets, global warming and so on.  Such negativity may well be justified in some of these areas.  However, I can’t help but feel we are getting a little carried away when we say that the cataclysmic destruction of Tokyo is not only inevitable but imminent.  I know I am thinking out loud here, but I, for one, don’t accept it.

Thank you for reading and take care

Our Man in Japan