That's what I thought of when I read your post.
There are many ways in which God uses the natural weather and climatology around us to alert us to current spiritual problems in our lives which separate us from Him.
He has done this many times in the past, and those times are recorded both in History and in Scriptures.
Minor earthquakes and tremors are one of the gentlest ways of forewarning.
When they increase in strength it reflects the severity of the spiritual instability in the lives of people.
It is not just a specific warning for the specific group of people which are affected, but is also meant as a broader, generalized warning to be spread abroad, so that the people who hear about or who see the resulting damage of the earthquakes might take heed to examine the foundations of their own lives, and to make amends and changes that are necessary in order to come into harmony with God.
The torrential rains and floods which cleanse the land are another way that God uses the natural land and the elements around us to alert us of changes that need to be made, and also to the spiritual pollution in our own lives, and from which we need cleansing by the water and the Word of God.
Raging fires and tsunami's also have the cleansing effect by the elements of water and fire, but earthquakes in particular signify the instability of the foundations of our lives, so that we might shore up, straighten, and strengthen them while there is still time to do so.
Stronger earthquakes that topple buildings and leave only rubble behind indicate that a new, solid spiritual foundation must be built. Not one that can be shaken or destroyed, and which is built upon sands that themselves shift and shake, but one sure foundation that is based on the Word of God.
