Downs, Sandra

Explains what rocks, minerals, and gemstones are found on the earth and how they are used by people.

Describes and explains the geological phenomena of earthquakes, landslides, sinkholes, quicksand, and avalanches.

Examines the different forces of erosion, such as wind, waves, acid rain, and glaciers, explains how they affect the topography of the earth, and describes their results, including dust storms, sand dunes, and caves.