The Unified Soil Classification System (USCS) is a soil classification system used in engineering and geology to describe the texture and grain size of a soil. The classification system can be applied to …

The Official Soil Series Description (OSD) database is a national collection of more than 20,000 detailed soil series descriptions. These descriptions, in a text format, serve as a national standard.

The Unified Soil Classification System uses a two-letter system to name different soil types. The chart below also includes a plasticity chart that is used to determine the classification of fine-grained soils.

Where soils are configured in layers, i.e., where a layered geologic structure exists, the soil must be classified on the basis of the soil classification of the weakest soil layer.

Nov 23, 2025 · The two principal systems of soil classification in use today are the soil order system of the U.S. Soil Taxonomy and the soil group system, published as the World Reference Base for Soil …

Soil Classification concerns the grouping of soils with a similar range of properties (chemical, physical and biological) into units that can be geo-referenced and mapped.

Different systems have been developed in different countries, so in this section we will cover the basics of the classification system commonly used in the US, as well as the younger world reference base …

Soil classification deals with the systematic categorization of soils based on distinguishing characteristics as well as criteria that dictate choices in use. Soil classification is a dynamic subject, …

To ensure proper application of the criteria for classifying soils, the latest version of the “Keys to Soil Taxonomy ” is needed. In addition, this guide omits all information needed to classify soils to the …

• Soils have oxic, kandic, spodic, argillic, natric and cambic horizons due to the amount of time they have been developing and the weathering environment • Because these features represent differences in …