OUTLINE. Introduction Precambrian Earth History The Paleozoic Geography of Earth Paleozoic Evolution of North America The History of Paleozoic Mobile Belts The Role of Microplates The Breakup of Pangaea The Mesozoic History of North America GEO-FOCUS 18.1: Petrified Forest National Park
OUTLINE • Introduction • Precambrian Earth History • The Paleozoic Geography of Earth • Paleozoic Evolution of North America • The History of Paleozoic Mobile Belts • The Role of Microplates • The Breakup of Pangaea • The Mesozoic History of North America • GEO-FOCUS 18.1:Petrified Forest National Park • Cenozoic Earth History • Geo-Recap
OBJECTIVES 1 The Precambrian encompasses more than 88% of all geologic time, yet we know less about this episode in Earth history than we do about the other eras. 2 At the beginning of the Paleozoic, six major continents were present, and they assembled into the supercontinent Pangaea by the end of the Paleozoic. 3 The breakup of Pangaea took place in four general stages, beginning during the Triassic. 4 The geologic record of the Cenozoic is more thoroughly understood than the records of earlier eras. 5 An episode of widespread glaciation took place during the Pleistocene Epoch.