This second edition of the leading book on Grand Canyon geology contains the most recent discoveries and interpretations of the origin and history of the canyon. It includes two entirely new chapters: one on debris flow in the Canyon and one on the impact of water flow releases from the GlenCanyon Dam. All chapters have been updated where necessary and all photographs have been replaced or re-screened for better resolution. Written by acknowledged experts in stratigraphy, paleontology, structural geology, geomorphology, volcanism and seismology, this book offers a wealth of informationfor geologists and general readers interested in acquiring an understanding of the geological history of this great natural wonder.