The Hammer of Eden — Ken Follett

The FBI doesn't believe it. The Governor wants the problem to disappear. But agent Judy Maddox knows the threat is real: An extreme group of eco-terrorists has the means and the know-how to set off a massive earthquake of epic proportions. For California, time is running out.

Now Maddox is scrambling to hunt down a petty criminal turned cult leader turned homicidal mastermind. Because Judy knows that the dying has already begun. And soon, the earth will violently shift, bolt, and shake down to its very core....