Region of the Earth's crust that is, or has been active, and in which fold mountains are, or were, formed.
Pellant, p. 251
Sources
- Pellant, Chris. The Complete Book of Rocks and Minerals, Dorling Kindersley Inc.: New York (1995)
Region of the Earth's crust that is, or has been active, and in which fold mountains are, or were, formed.
Pellant, p. 251