Petersburg, West Virginia. Petersburg is a city in Grant County, West Virginia, USA. The population was 2,467 at the 2010 census. It is the county seat of Grant County. Contents.
The particles that make up soil are categorized into three groups by size: sand, silt, and clay. Sand particles are the largest and clay particles the smallest. Although a soil could be all sand, all clay, or all silt, that's rare. Instead most soils are a combination of the three.
The texture of a soil can be determined from its sand, silt, and clay content using a textural triangle. The triangle above (Figure 2) is the one created by the U.S. Department of Agriculture's Natural Resources Conservation Service and is primarily used in the United States.