Genesis 1: 14 And God said, let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and years.
15 And let them be for lights in the firmament of the heaven to give light upon the earth: and it was so.
16 And God made two great lights; the greater light to rule the day, and the lesser to rule the night: he made the stars also.
17 And God set them in the firmament of the heaven to give light upon the earth.
The Northridge quake was January 17, a day that will live into enfiny. One year to the day was the Kobe quake. So you see it varies in degree from year to year. For seasons and signs jus like He said.