Chapter 6 - Crustal and mantle evolution

Abstract

This chapter discusses evolution of the crust and mantle through 4.6 Gyr of Earth's history. It begins with a discussion of the Hadean era focusing on new and exciting research on the ages of detrital zircons and the origin and composition of the earliest crust. It includes a brief summary of Earth's oldest rocks. Models of crustal origin and growth are presented with a detailed discussion of the growth rate of continental crust including problems of recycling into the mantle and juvenile crust production. The crustal age gap at 2.4–2.2Ga is discussed, as are secular changes in the composition, rock associations, and tectonic settings of the crust, the controversial topic of when plate tectonics began. The chapter ends with discussion of secular changes in the mantle, including the lithosphere, and models for Earth's thermal history.