Soil Spot Points of Loudoun County, VA (2010) | |
Data format: SDE Feature Class File or table name: GISDBB.GISBROW.SOIL_SPOINTS_POINT Coordinate system: Lambert Conformal Conic Theme keywords: geoscientificInformation, streams, lake, pond, marsh, wet spot, gully, sink hole, depression, escarpments, rock outcrops, gravel, stones |
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Abstract:
The soil spot points, or map symbols layer is a subset of the soils map. Spot points are isolated areas within a symbol that are designated with a symbol because the extent is too small to separate into another mapping unit. These points or symbols include areas such as sinkholes, springs, stony areas, wet spots, etc. |
Metadata elements shown with blue text are defined in the Federal Geographic Data Committee's (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM). Elements shown with green text are defined in the ESRI Profile of the CSDGM. Elements shown with a green asterisk (*) will be automatically updated by ArcCatalog. ArcCatalog adds hints indicating which FGDC elements are mandatory; these are shown with gray text.
The soil spot points, or map symbols layer is a subset of the soils map. Spot points are isolated areas within a symbol that are designated with a symbol because the extent is too small to separate into another mapping unit. These points or symbols include areas such as sinkholes, springs, stony areas, wet spots, etc.
As a subset of the soils information, the spot points layer should be used in conjunction with the other soils layers. Spot points show specific areas that require special interpretation and/or land use which differs from the surrounding map unit.
Data are stored in the corporate ArcSDE Geodatabase as a point feature class. The coordinate system is Virginia State Plane (North), Zone 4501, datum NAD83 HARN (vertical datum, if applicable, NAVD88), US Survey foot units.
publication date
Every reasonable effort has been made to assure the accuracy of these data. Loudoun County, Virginia does not assume any liability arising from the use of these data. These data are provided without warranty of any kind, expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular service. Reliance on these data is at the risk of the user. These data were generated for use by Loudoun County and are available to the public. These data are intended for use at 1:2400 scale or smaller. Acknowledgement of Loudoun County would be appreciated in products derived from this data.
1 Harrison Street SE, 2nd floor
mail stop 60
Retention of attribute accuracy throughout the coverage to geodatabase feature class coversion process was ensured by a QA/QC programmatic check. To meet satisfactory QA/QC requirements the input coverage and output feature class must have, on a record by record basis, identical attribution when comparing all concatenated fields to all the user-defined attribution.
Topologically clean
Features may have been eliminated or generalized due to scale and intended use. To assist Loudoun County, Virginia in the maintenance of the data, please provide any information concerning discovered errors, omissions, or other discrepancies found in the data.
Retention of coordinate accuracy throughout the coverage to geodatabase feature class conversion process was ensured by a QA/QC programmatic check. To meet satisfactory QA/QC requirements the input coverage and output feature class must have the same record total, and on a record by record basis, area, perimeter, and length differential of less than +/- 0.5%.
originated soil mapping units and concepts for agricultural uses in Loudoun County
revised soil survey for Loudoun County to emphasize general uses
The Soil Survey of Loudoun County (field work) was conducted between 1947 and 1952 by soil scientists from Virginia Tech and the USDA Soil Conservation Service. Soils were originally shown on 1938 aerial photography at a scale of 4"= -1 mile; soils were later redrafted to a scale of 1" = 1666' (1:20000) for publication in the USDA's Soil Survey of Loudoun County, Virginia, Series 1951, Number 8, which was issued in September 1960. This publication is out of print, and the supply of copies for public distribution has been exhausted. A revision of the soil survey for Loudoun County has been completed. The manuscript is currently undergoing technical review and publication of the final document is anticipated during the 2006 calendar year.
As part of the County's Geographic Information System (G.I.S.) mapping project, the soil survey maps were redrafted onto the County's base maps, at a scale of 1" = 200', then digitized. This information is available at the Office of Mapping and Geographic Information or through the County soil scientist in the Cooperative Extension Office . Although these updated soil maps rely heavily on the original soil survey, changes in both location of mapping unit lines and mapping unit descriptions/interpretations have occurred
The soils map is continuously being updated based on field site inspections and therefore the soils map merely represents a point in time. Many new soil series concepts have been developed and the emphasis has changed from primarily agricultural use to include urban uses. This report is geared to mapping unit potential for general uses. Mapping unit potential ratings attempt to describe the broad range of conditions found in any given mapping unit for the noted uses. For more site-specific soil interpretations contact the County Soil Scientist in the Cooperative Extension Office.
This data set was part of a batch process that converted legacy data from ArcInfo coverage in Librarian to a single-tiled ArcInfo coverage in preparation for a final coversion to ArcSDE Geodatabase Feature Classes. Data were extracted from Librarian using the EXTRACT TOPOLOGICAL command. Multi-tiled data sets were extracted into multiple coverages and then combined based on the feature type(s). Layers with both polygon and arc feature classes were processed with the Arc commands, MAPJOIN and DISSOLVE. Arc feature classes alone were processed with the Arc commands, APPEND and DISSOLVE. Layers with both arc and point feature classes and point feature classes alone were processed with the Arc command, APPEND. When used, the Arc command, DISSOLVE, was given with the <#all> option. All coverages were then reprojected to HARN 83 using the following .prj file specifications: INPUT PROJECTION STATEPLANE UNITS FEET ZONE 5551 DATUM NAD27 NADCON PARAMETERS OUTPUT PROJECTION STATEPLANE UNITS FEET FIPSZONE 4501 DATUM HPGN NADCON PARAMETERS END This dataset was then converted to a feature class in a geodatabase in ArcSDE.
Feature geometry.
ESRI
Internal feature number.
ESRI
Number code with one-to-one relation to SP_SYMBOL field; Tells computer what symbol to make spot point
Loudoun County
3 digit Ad-hoc symbol code that identifies a soil point significantly different from mapping unit that is too small to portray with a polygon feature
Loudoun County
Field is obsolete and no longer maintained
Loudoun County
Field is obsolete and no longer maintained
Loudoun County
Field is obsolete and no longer maintained
Loudoun County
Field is obsolete and no longer maintained
Loudoun County
Source that created or modified feature class
Loudoun County
Date feature class created or modified
Loudoun County
Not for public distribution. Internal User ID of editor creating or modifying a feature.
Loudoun County
SP_SOIL: Number code with one-to-one relation to SP_SYMBOL field; Tells computer what symbol to make spot point
Code Symbol -4 Unknown 0 Unknown 2 BPI 3 ROC 4 SNK 5 GRA 6 SPR 7 MAR 9 CLA 10 MDL 11 STN 12 WET 13 SAN 15 SSS 16 TEC 17 CEM
SP_SYMBOL: 3 digit Ad-hoc symbol code that identifies a soil point significantly different from mapping unit that is too small to portray with a polygon feature
Code Description "SP Unknown BPI Borrow pit CEM Cemetary CLA Clay spot GRA Gravely spot MAR Marsh MDL Made land ROC Rock SAN Sandy spot SNK Sink hole SPR Spring SSS Soil sample spot STN Stoney spot TEC Terrace capping WET Wet spot
SP_UPD_SOURCE: Source that created or modified feature class
Source Description 0 Undetermined 1 Legacy 2 County 3 Contract
1 Harrison Street S.E., 2nd floor
MS 65
Every reasonable effort has been made to assure the accuracy of these data. Loudoun County, Virginia does not assume any liability arising from the use of these data. These data are provided without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular service. Reliance on these data is at the risk of the user.
ESRI Personal Geodatabase Feature Class
ESRI Shapefile
AutoCad Digital Exchange File
Size limit: 4.5 GB. Visit our website at: http://www.loudoun.gov/omagi, click on "Loudoun County Mapping Documents & Order Forms." The "Forms" directory will lead you to custom & standard (countywide) data order forms. Hardcopy maps may also be available; please contact the Mapping Office Public Information Counter for more information regarding all data requests.
1 Harrison Street SE, 2nd Floor
MS 65