First of all, I would be afraid of earthquakes, we have tornadoes where I live and any warning sends me to the shelter area.
As for the Crohn's, I think you are perhaps having anticipatory anxiety, you are worrying about the what ifs? As we don't know the what ifs I would hope you can overcome this fear by staying in the moment and living today. Try not to asume every twinge that seems wrong is going to be a blockage. I know it is easy for me to say this but it takes lots of practice and anyone that can live in your land with the earthquake threat has lots of fortitude. I believe in you.Hugs