Earthquakes are one of the hallmarks of the Final Redemption (Geula). In his book "Light of the Torah", the Tzemakh-Tzedek writes (at the beginning of the commentary on the weekly chapter "Genesis"): "Perhaps an earthquake is a sign of the coming Geula (Redemption), as it says:" Lift up your eyes to the heavens, look at the earth beneath; the heavens will vanish like smoke, the earth will wear out like a garment and its inhabitants die like flies. But my salvation will last forever, my righteousness will never fail."( Isaiah 51:6 ).
In 1991 (5750), at a parade in honor of the holiday of Lag B'Omer, Rebbe King Moshiach שליט"א, delivered a speech in which he mentioned the terrible earthquake that had occurred in Iran six weeks prior.
"As to the world disasters (e.g. earthquakes), we do not need to be afraid as there were such in the past as well. After all, the true meaning of this is to bring a reminder of the existence of the L-rd of Peace to those who, for some reason, forgot about Him and to shake them out from the illusory peace, and to know now and forever that the world is ruled by its Creator, and the source of goodness and good, to such a large and vast extent that can completely paralyze and destroy the forces of evil in the world.”