Models are representations of objects or processes and are useful in studying things that are difficult to observe firsthand, such as things that are very large or very small, or events that occur over very long periods of time. Topographic maps, relief maps, and aerial photos can be used to study landforms. The structure and boundaries of a watershed can be identified on topographic maps, relief maps, and aerial photos. Cartographers are map-makers. Humans effect the processes of erosion and deposition.
People can choose to restore and conserve soil and landforms.
Rocks and mineral have observable properties. Rocks are mixtures of minerals. Rocks exhibit a variety of properties including shape, size, color, and texture. Minerals have different properties such as color, scratchability, and luster. Minerals cannot be physically separated into other materials.