This is the student's text for one of the units of the Intermediate Science Curriculum Study (ISCS) for level III students (grade 9). The chapters contain basic information on the processes that shape the earth, activities related to the subject, and optional excursions. A section of introductory notes to the student discusses how to use the book and how the class will be organized. Illustrations accompany all instructions and the students are encouraged to select proper equipment based on the illustrations. (SA)