See Module Preview for initial information and a Powerpoint Presentation. If you need a review, go to our Planetary Geology Internet Course for information on planetary processes, rock-forming minerals , the rock cycle and earth geological processes . You might want to visit the Planetary Geology Home Page for additional information. Soils Soil is one of the most important earth materials we encounter each day, but finding an exact definition of soil is difficult. The definition depends on the context of the question.
Soil scientists focus on the physical and chemical properties of soil.
Engineers think of soil as any earth material that can be removed from a site without blasting. Engineers focus on particle size and the amount of organic material in soil when they consider the properties of soil for engineering applications. Environmental geologists must understand soil from many perspectives. Soil characteristics affect agriculture, engineering, hydrology, natural hazards and other aspects of land use. Understanding soil development and soil character is crucial to good land use planning.