In the first chapter, Erickson reveals the physical mechanisms responsible for most geologic cataclysms. Dubbing them the "new geology," Erickson masterfully presents these mechanisms--plate movements and mantle convections--so as to intrigue the reader with them through accounts of earthquakes, volcanoes, and tidal waves in all corners of the world. Yet he also affords a generous sampling of more common cataclysms, including landslides, soil creep, mudflows, and wind-induced dust storms and their marine counterparts, submarine slides. Erickson reviews glaciation both past and present as well as the effects of foreign objects from space. Particularly striking is the concluding chapter's discussion of issues of cause and effect in accounting for extinctions.