Source of Gravel By Soil Type
National Park Service: Thomas Colson. 2011. Source of Gravel By Soil Type
Gravel consists of natural aggregates (2 to 75 millimeters in diameter) suitable for commercial use with a minimum of processing. It is used in many kinds of construction. Specifications for each use vary widely. Only the probability of finding material in suitable quantity is evaluated. The suitability of the material for specific purposes is not evaluated, nor are factors that affect excavation of the material. The properties used to evaluate the soil as a source of gravel are gradation of grain sizes (as indicated by the Unified classification of the soil), the thickness of suitable material, and the content of rock fragments. If the bottom layer of the soil contains gravel, the soil is considered a likely source regardless of thickness. The assumption is that the gravel layer below the depth of observation exceeds the minimum thickness. The ratings are for the whole soil, from the surface to a depth of about 6 feet. Coarse fragments of soft bedrock, such as shale and siltstone, are not considered to be gravel. The soils are rated "good," "fair," or "poor" as potential sources of gravel. A rating of "good" or "fair" means that the source material is likely to be in or below the soil. The bottom layer and the thickest layer of the soils are assigned numerical ratings. These ratings indicate the likelihood that the layer is a source of gravel. The number 0.00 indicates that the layer is a poor source. The number 1.00 indicates that the layer is a good source. A number between 0.00 and 1.00 indicates the degree to which the layer is a likely source. The map unit components listed for each map unit in the accompanying Summary by Map Unit table in Web Soil Survey or the Aggregation Report in Soil Data Viewer are determined by the aggregation method chosen. An aggregated rating class is shown for each map unit. The components listed for each map unit are only those that have the same rating class as listed for the map unit. The percent composition of each component in a particular map unit is presented to help the user better understand the percentage of each map unit that has the rating presented. Other components with different ratings may be present in each map unit. The ratings for all components, regardless of the map unit aggregated rating, can be viewed by generating the equivalent report from the Soil Reports tab in Web Soil Survey or from the Soil Data Mart site. Onsite investigation may be needed to validate these interpretations and to confirm the identity of the soil on a given site.
- Type
- Geospatial Dataset
- Authors
- National Park Service: Thomas Colson
- Date of Issue
- 2011-10-10
- Units
- GRSM
- Keywords
- APHN, Appalachian Highlands Network, Blockhouse NC, Blount County, Bryson City NC, Bunches Bald NC, Cades Cove TN, Calderwood TN, Clingmans Dome NC, Cocke County, Cove Creek Gap NC, Dellwood NC, Environment, Fines Creek NC, Fontana Dam NC, Gatlinburg TN, Graham County, Gravel Source, Great Smoky Mountains National Park, GRSM, Hartford TN, Haywood County, Jones Cove TN, Kinzel Springs TN, Luftee Knob NC, Mount Guyot TN, Mount Le Conte TN, National Standards for Spatial Digital Accuracy (NSSDA), Natural Resource Inventory And Monitoring Program, NC, Noland Creek NC, None, North Carolina, NRIM, Pigeon Forge TN, Richardson Cove TN, SERO, Sevier County, Silers Bald NC, Smokemont NC, Soil Survey, Soil Survey Geographic, Soils, Southeast Region, SSURGO, Swain County, Tallassee TN, Tapoco NC, Tennessee, Thunderhead Mountain NC, TN, Tuskeegee NC, U.S., United States, US, USA, Waterville TN, Wear Cove TN, Whittier NC