Which size range characterizes gravel in soil classification?

• A. 0.002 mm to 0.075 mm
• B. 2 mm to 3 mm
• C. 2 mm and larger
• D. 0.075 mm to 2 mm

Answer: (C)

Gravel is classified within soil categorization based on its particle size, and the correct range for gravel is particles that are 2 mm and larger. This classification is fundamental for various engineering and geological applications, including construction and soil analysis. In this context, gravel consists of larger fragments, and its size allows for important properties such as drainage and structural stability.

The other size ranges presented in the options represent different types of soil particles. For instance, the size range from 0.002 mm to 0.075 mm is indicative of fine silts and clays, which have different handling and engineering characteristics. The range from 0.075 mm to 2 mm includes sands and small aggregates, which also differ from gravel in terms of compaction and water retention properties. The range of 2 mm to 3 mm might describe a specific category of gravel or small stones, but it does not encompass all gravel sizes, since gravel includes all particles larger than 2 mm. Therefore, understanding the definition that includes all particles from 2 mm and larger is vital in correctly identifying gravel within the broader context of soil classification.