National Geodetic Survey (NGS) Geodetic Control Stations, (Horizontal and/or Vertical Control), March 2009

Metadata from the RGIS Metadata Repository

Identification Information

Title National Geodetic Survey (NGS) Geodetic Control Stations, (Horizontal and/or Vertical Control), March 2009
Date 2009-03-11
Date Type Publication
Cited Responsible Party
Organization Name NOAA, National Geodetic Survey
Role identify
Presentation Form vector digital data
Abstract This data contains a set of geodetic control stations maintained by the National Geodetic Survey. Each geodetic control station in this dataset has either a precise Latitude/Longitude used for horizontal control or a precise Orthometric Height used for vertical control, or both. The National Geodetic Survey (NGS) serves as the Nation's depository for geodetic data. The NGS distributes geodetic data worldwide to a variety of users. These geodetic data include the final results of geodetic surveys, software programs to format, compute, verify, and adjust original survey observations or to convert values from one geodetic datum to another, and publications that describe how to obtain and use Geodetic Data products and services.
Purpose Provide a base of reference for latitude, longitude and height throughout the United States.
Data Set Credit NOAA, National Geodetic Survey and cooperating organizations
Status Complete
Point of Contact
Individual Name Craig Larrimore
Organization Name
Position Name IT Specialist
Role Point of contact
Voice 301-713-3257x152
Facsimile 301-713-4172
Address
Delivery Point SSMC2/9152 1315 East-west Highway
City Silver Spring
Administrative Area MD
Postal Code 20910
Country USA
Electronic Mail Address Craig.Larrimore@noaa.gov
Maintenance and Update Frequency Continually
Descriptive Keywords NSRS, geodetic, horizontal control, vertical control, ellipsoid height, benchmark, orthometric height, latitude, longitude
Access Constraints Geodetic Data are in the public domain, not restricted from access or distribution.
Use Constraints Not restricted; Geodetic Data, including software were developed and compiled with U.S. Government funding; no proprietary rights may be attached to them nor may they be sold to the U.S. Government as part of any procurement of ADP products or services.
Language English
Topic Category location
Extent
Geographic Bounding Box
West Bound -109.056738
East Bound -103.002383
North Bound 37.0
South Bound 31.332258
Temporal Extent
DateTime 2009-02-12
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Distribution Information

Distributor
Individual Name
Organization Name Earth Data Analysis Center
Position Name Clearinghouse Manager
Role Point of contact
Voice 505-277-3622 ext. 230
Facsimile 505-277-3614
Address
Delivery Point MSC01 1110
Delivery Point 1 University of New Mexico
City Albuquerque
Administrative Area NM
Postal Code 87131-0001
Country USA
Electronic Mail Address clearinghouse@edac.unm.edu
Transfer Options
Online Resource ZIP
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Spatial Reference Information

Spatial References
Spatial Reference D_North_American_1983_HARN
Online Reference EPSG:6152
Spatial Reference Geodetic Reference System 80
Online Reference EPSG:7019
Spatial Reference North American Vertical Datum of 1988 (NAVD 88), including Ellipsoidal and Orthometric Heights.
Online Reference EPSG:5103
Indirect Spatial Reference New Mexico (35)
Geometric Object Type Entity point
Geometric Object Count 14899
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Data Quality Information

Attribute Accuracy Report
Report Horizontal control stations (those with precise Latitude, Longitude) were established in accordance with FGDC publications "Standards and Specifications for Geodetic Accuracy Standards" and "Geometric Geodetic Accuracy Standards and Specifications for Using GPS Relative Positioning Techniques" The final Latitude, Longitude of these stations were determined by a least squares adjustments of the horizontal observations. Horizontal control station have Latitude, Longitudes displayed to 5 places and are identified by attribute POS_SRCE = 'ADJUSTED' Lesser quality Latitude, Longitudes may also be preset in the dataset. These are identified by a POS_SRCE attributes HD_HELD1, HD_HELD2, or SCALED. These lesser quality positions are described at: http://www.ngs.noaa.gov/cgi-bin/ds_lookup.prl?Item=SCALED Vertical control stations (those with precise Orthometric Heights) were established in accordance with FGDC publications "Standards and Specifications for Geodetic Accuracy Standards" The final Orthometric Height of these stations were in most cases determined by a least squares adjustments of the vertical observations but in some cases may have been keyed from old survey documents. Vertical control stations have Orthometric Heights displayed to 2 or 3 places and are identified by attribute ELEV_SRCE of ADJUSTED, ADJ UNCH, POSTED,READJUST,N HEIGHT,RESET,COMPUTED Lesser quality Orthometric Heights may also be preset in the dataset. These are identified by a ELEV_SRCE attributes GPS_OBS, VERT_ANG, H_LEVEL, VERTCON, SCALED. These lesser quality orthometric heights are described at: http://www.ngs.noaa.gov/cgi-bin/ds_lookup.prl?Item=SCALED IMPORTANT - Control stations do not always have both precise Latitude, Longitude AND precise Orthometric Height. A horizontal control station may have a orthometric height associated with it which is of non geodetic quality. These types of heights are displayed to 0, 1, or 2 decimal places. Worst case being off by +/- 1 meter. LIKEWISE - A Vertical control station may have a Latitude, Longitude associated with it which is of non geodetic quality. These types of Latitude, Longitudes are displayed to 0, 1 or 2 decimal places. Worst case being off by +/- 180 meter. Refer to http://www.ngs.noaa.gov/cgi-bin/ds_lookup.prl?Item=SCALED for a description of the various type of methods used in determining the Latitude, Longitude, and Orthometric Height. Attribute POS_CHECK and ELEV_CHECK indicate whether or not an observational check was made to the position and/or orthometric height. Care should be taken when using "No Check" coordinates. If attribute ELEV_SRCE = 'VERTCON' then the Orthometric Height was determined by applying NGS program VERTCON to an Old NGVD 29 height. In most areas VERTCON gives results to +/- 2 cm. See http://www.ngs.noaa.gov/TOOLS/Vertcon/vertcon.html for a more detailed explanation of VERTCON accuracy. Ellipsoid Heights are also present in the dataset. The ellipsoid heights consist of those determined using a precise geoid model, which are displayed to 2 decimal places and are considered good to +/- .005 meters, and those displayed to 1 decimal place and are considered only good to +/- .5 meters
Quantitative Attribute Accuracy Assessment
Attribute Accuracy Value 95 percent confidence level for geodetic quality data.
Attribute Accuracy Explanation Geodetic Data are continuously being processed; their standards and specifications are being reviewed for next publication release. "Standards and Specifications for Geodetic Control Networks", 1984 and "Geometric Geodetic Accuracy Standards and Specifications for Using GPS Relative Positioning Techniques," FGCS (formally FGCC) publication version 5.0 1989, are most current published documents.
Horizontal Positional Accuracy Report
Report The description of tests are explained in "Geometric Geodetic Accuracy Standards and Specifications For Using GPS Relative Positioning Techniques," FGCS (formally FGCC) publication version 5.0, 1989. .05 meters for highest order of accuracy.
Quantitative Horizontal Positional Accuracy Assessment
Horizontal Positional Accuracy Value .05
Horizontal Positional Accuracy Explanation Horizontal positional accuracy statements pertain to horizontal control stations only. i.e. Those with geodetic quality Latitude, Longitudes. Positional Accuracy explanation contained in "Geometric Geodetic Accuracy Standards and Specifications For Using GPS Relative Positioning Techniques," FGCS (formally FGCC) publication version 5.0, 1989, (See table 1, p6). with the exception of Order A and Order B which have an accuracy of as described at: http://www.ngs.noaa.gov/cgi-bin/ds_lookup.prl?Item=HORZ%20ORDER
Vertical Positional Accuracy Report
Report The description of tests are explained in "Geometric Geodetic Accuracy Standards and Specifications for Using GPS Relative Positioning Techniques," FGCS (formally FGCC) publication version 5.0, 1989, (See table 1, p6). .05 meters for highest order of accuracy
Quantitative Vertical Positional Accuracy Assessment
Vertical Positional Accuracy Value .05
Vertical Positional Accuracy Explanation Vertical positional accuracy statements pertain to vertical control stations only. i.e. Those with geodetic quality Orthometric Heights. Orthometric Height accuracy explanation is contained in FGDC publication "Standards and Specifications for Geodetic Control Networks" with the exception of vertical control of class 0 POSTED and READJUSTED Heights which are described at: http://www.ngs.noaa.gov/cgi-bin/ds_lookup.prl?Item=VERT%20ORDER Ellipsoid height accuracy explanation contained in "Geometric Geodetic Accuracy Standards and Specifications for Using GPS Relative Positioning Techniques," FGCS (formally FGCC) publication version 5.0, 1989. (see table 1, p6). The accuracies for ellipsoid heights are described at: http://www.ngs.noaa.gov/cgi-bin/ds_lookup.prl?Item=ELLP%20ORDER
Logical Consistency Report FGCS sponsored testing in cooperation with equipment manufacturers and National Institutes of Standards and Technology, Gaithersburg, MD 20850
Completeness Report This dataset DOES NOT include destroyed marks. All other non-publishable marks are NOT included. Non-publishable criteria is available at http://www.ngs.noaa.gov/cgi-bin/craigs_lib.prl?HELP_NONPUB=1
Lineage
Source Information
Source Citation
Source Scale Denominator
Type of Source Media paper, Web
Source Time Period of Content
DateTime 1994
Source Currentness Reference publication date
Source Citation Abbreviation Blue Book
Source Contribution The geodetic data must be submitted in the digital formats specified in the FGCS (formally FGCC) publication "Input Formats and Specifications of the National Geodetic Survey Data Base" which describes the formats and procedures for submission of data for adjustment and assimilation into the National Geodetic Survey Data Base. Separate volumes of this publication refer to horizontal (volume 1), vertical (volume 2), and gravity (volume 3) control, and are available from NOAA, National Geodetic Survey, 1315 East-West Hwy, Code N/CGS1, Silver Spring, MD, 20910 (1-301-713-3242). Note guidelines for submission of three-dimensional Global Positioning System (GPS) relative positioning data are contained in annex L to volume 1.
Process Step
Process Description The National Geodetic Survey produces geodetic data. Geodetic data comprise the results of geodetic surveys to determine, among other things, latitude, longitude, height, scale, and orientation control. The National Geodetic Survey original field survey project observations and final reports are accessioned into records system of the National Archives and Records Administration of the U.S.A. These surveys provide information valuable for a variety of uses in the mapping, charting and surveying community. The NGS' final product is the geodetic data sheet. Geodetic data sheets are comprehensive summaries of all published information for a given geodetic reference point, including: the geographic position and/or height based on the current reference datum, condition of the survey mark when it was last visited, a description of where the point is located and how to reach it, and an explanation of the terms used in the data sheet. In support of these geodetic data, the NGS provides software, publications, and various user services, including geodetic advisor program, instrument calibration, surveying standards, and technical workshops. This dataset contains certain information extracted from the above mentioned data sheet.
Source Used Citation Abbreviation Blue Book
Process Date Not complete
Process Time
Process Contact
Individual Name Craig Larrimore
Organization Name
Position Name IT Specialist
Role Point of contact
Voice 301-713-3257x152
Facsimile 301-713-4172
Address
Delivery Point SSMC2/9152 1315 East-west Highway
City Silver Spring
Administrative Area MD
Postal Code 20910
Country USA
Electronic Mail Address Craig.Larrimore@noaa.gov
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Metadata Reference Information

File Identifier 458f421e-1e35-4ca4-887a-8b0d0f74ab7d
Metadata Language English
Hierarchy Level Dataset
Date Stamp 2019-10-17
Metadata Standard Name ISO 19115:2003
Metadata Standard Version 1.0
Metadata Contact
Individual Name
Organization Name Earth Data Analysis Center
Position Name Clearinghouse Manager
Role Point of contact
Voice 505-277-3622 ext. 230
Facsimile 505-277-3614
Address
Delivery Point MSC01 1110
Delivery Point 1 University of New Mexico
City Albuquerque
Administrative Area NM
Postal Code 87131-0001
Country USA
Electronic Mail Address clearinghouse@edac.unm.edu
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