I chose Earth Science. It wasn't a popular choice, but it's what I enjoyed studying so I thought it was the logical choice. Looking back, math or reading would have been the wiser choice since that's what is tested in schools.
Oh, and I live in earthquake country now too. It's almost laughable.
Because I am an Earth Science nerd and because I live in the San Francisco area, I am constantly checking the USGS website. Not only have I learned all the fault lines, but I learned the USGS has some great teaching materials for FREE! You must take a look at this fabulous site.