I read this while studying for my Geology exams - perhaps not the best study technique, but certainly more entertaining than the textbooks. Michael Benton presents an interesting topic in a way which is very accessible without becoming simplistic or patronising and brings the geology alive.
An earlier reviewer comments that the first few chapters are more general and not directly related to the end-Permian extinction which is the main topic of the book. That's a fair comment, but those chapters also set the scene for the reader who is not familiar with the progress of geological thought, and the real significance of the realisation that catastrophism does indeed have its place in the way we think about the history of the Earth.
In the mid-nineteenth century, and until the late twentieth, it was believed that geological processess were generally gradual, and that processes observed today could be used to explain geological events in the past. This came out of a rejection of biblical ideas of creation and floods, and was a good way to explain many geological phenomena. But occasionally, very major and unusual events do occur and geologists have perhaps struggled to accept the evidence before them because of these deep-seated beliefs.
From the discovery of plate tectonics in the sixties, through the understanding of mass extinctions in the eighties and nineties, the science has been turned on its head within my own lifetime. Its a fabulous time to being studying geology, and books like this which bring it to a general audience are to be applauded.