Lyric discussion by heavenscloudrm 

Succumbing to the fault line doesn't necessarily mean that California falls into the ocean, just suffers a large earthquake.

I think that the 'heaved relief' line means that they were relieved that they survived, or that they were not in California when it happened.... You might see a disaster on TV, and you are horrified by the violence of it and at the same time, you feel relieved that you and your family are safe... That is what this song brings out in me...

I agree with this interpretation of the line. Colin doesn't need to explicitly say "heaved A SIGH of relief" to get across the basic idea there (it doesn't scan with the music anyway). The character and his/her fellows are relieved that they weren't among the dead of California. It's simultaneously a positive ("hurray, we aren't dead") and negative ("who cares about the dead, so long as we are not among them!") sentiment that is all-too-common among insulated middle America, people whose only exposure to large-scale tragedy tends to be via newsreel footage - a not-unfrequent target of Colin's gentle criticisms....

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