The conference was held in Snowbird, Utah, October 1988, as a sequel to the Conference on Large Body Impacts held in 1981, also in Snowbird. This volume contains 58 peer-reviewed papers, arranged into sections that cover the major themes of the conference: catastrophic impacts, volcanism, and mass mortality; geological signatures of impacts; environmental effects of impacts; patterns of mass mortality; volcanism and its effects; case histories of mass mortalities; and events and extinctions at the K/T boundary. Annotation copyrighted by Book News, Inc., Portland, OR

Sixty-five million years ago, a comet or asteroid larger than Mount Everest slammed into the Earth, inducing an explosion equivalent to the detonation of a hundred million hydrogen bombs. Vaporized detritus blasted through the atmosphere upon impact, falling back to Earth around the globe. Disastrous environmental consequences ensued: a giant tsunami, continent-scale wildfires, darkness, and cold, followed by sweltering greenhouse heat. When conditions returned to normal, half the plant and animal genera on Earth had perished. This horrific chain of events is now widely accepted as the solution to a great scientific mystery: what caused the extinction of the dinosaurs? Walter Alvarez, one of the Berkeley scientists who discovered evidence of the impact, tells the story behind the development of the initially controversial theory. It is a saga of high adventure in remote locations, of arduous data collection and intellectual struggle, of long periods of frustration ended by sudden breakthroughs, of friendships made and lost, and of the exhilaration of discovery that forever altered our understanding of Earth's geological history.