The geographic limits of USA including trust Territories, N/A, N/A, NSRS, geodetic, horizontal control, vertical control, ellipsoid height, benchmark, orthometric height, latitude, longitude
Provide a base of reference for latitude, longitude and height throughout the United States.
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.
NOAA, National Geodetic Survey and cooperating organizations
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.
West | -91.692696 | East | -88.098200 |
North | 35.001016 | South | 30.161195 |
Maximum (zoomed in) | 1:5,000 |
Minimum (zoomed out) | 1:150,000,000 |
ArcGIS Metadata ►
THEMES OR CATEGORIES OF THE RESOURCE location
EXPORT TO FGDC CSDGM XML FORMAT AS RESOURCE DESCRIPTION No
PLACE KEYWORDS The geographic limits of USA including trust Territories
STRATUM KEYWORDS N/A
THESAURUS ►
TITLE N/A
PUBLICATION DATE 2017-09-13 00:00:00
Hide Thesaurus ▲
TEMPORAL KEYWORDS N/A
THESAURUS ►
TITLE N/A
PUBLICATION DATE 2017-09-13 00:00:00
EDITION DATE 2017-09-13
Hide Thesaurus ▲
THEME KEYWORDS NSRS, geodetic, horizontal control, vertical control, ellipsoid height, benchmark, orthometric height, latitude, longitude
THESAURUS ►
TITLE geodesy
PUBLICATION DATE 2017-09-13 00:00:00
EDITION DATE 2017-09-13
Hide Thesaurus ▲
Hide Topics and Keywords ▲
PUBLICATION DATE 2004-01-01
EDITION latest available
PRESENTATION FORMATS hardcopy diagram
FGDC GEOSPATIAL PRESENTATION FORMAT Diagram
SERIES
NAME N/A
ISSUE N/A
OTHER CITATION DETAILS
Questions concerning this data may be addressed to NGS Information Services Branch EMail - ngs.software@noaa.gov Phone - 301-713-3242
Hide Citation ▲
RESPONSIBLE PARTY
ORGANIZATION'S NAME NOAA, National Geodetic Survey
CONTACT'S ROLE publisher
CONTACT INFORMATION ►
ADDRESS
DELIVERY POINT NOAA Campus, Silver Spring, MD
Hide Contact information ▲
RESPONSIBLE PARTY
ORGANIZATION'S NAME NOAA, National Geodetic Survey
CONTACT'S ROLE originator
Hide Citation Contacts ▲
DATASET LANGUAGES English (UNITED STATES)
STATUS completed
SPATIAL REPRESENTATION TYPE vector
CREDITS
NOAA, National Geodetic Survey and cooperating organizations
ARCGIS ITEM PROPERTIES
NAME NGS_Benchmarks_Sep_2017
LOCATION file://\\SWALKER- PC\E$\DATA\NGS_Benchmarks\NGS_Benchmarks_Sep_2017.shp
ACCESS PROTOCOL Local Area Network
Hide Resource Details ▲
EXTENT
GEOGRAPHIC EXTENT
BOUNDING RECTANGLE
WEST LONGITUDE -88.1
EAST LONGITUDE -91.6
SOUTH LATITUDE 30.2
NORTH LATITUDE 35
EXTENT DESCRIPTION
retrieval date
TEMPORAL EXTENT
DATE AND TIME 2017-09-06
EXTENT
GEOGRAPHIC EXTENT
BOUNDING RECTANGLE
EXTENT TYPE Extent used for searching
WEST LONGITUDE -91.692696
EAST LONGITUDE -88.098200
NORTH LATITUDE 35.001016
SOUTH LATITUDE 30.161195
EXTENT CONTAINS THE RESOURCE Yes
EXTENT IN THE ITEM'S COORDINATE SYSTEM
WEST LONGITUDE 322641.328714
EAST LONGITUDE 650790.674057
EXTENT CONTAINS THE RESOURCE Yes
Hide Extents ▲
POINT OF CONTACT
INDIVIDUAL'S NAME NGS Information Services Branch ORGANIZATION'S NAME NOAA, National Geodetic Survey CONTACT'S POSITION IT Specialist
CONTACT'S ROLE point of contact
CONTACT INFORMATION ►
PHONE
VOICE 301-713-3242
FAX 301-713-4172
ADDRESS
TYPE both
DELIVERY POINT SSMC2/9152 1315 East-west Highway
CITY Silver Spring ADMINISTRATIVE AREA MD POSTAL CODE 20910 COUNTRY US
E-MAIL ADDRESS ngs.software@noaa.gov
HOURS OF SERVICE
8:30am to 5:00pm EST
CONTACT INSTRUCTIONS
Prefer EMail
Hide Contact information ▲
Hide Resource Points of Contact ▲
RESOURCE MAINTENANCE
UPDATE FREQUENCY continual
Hide Resource Maintenance ▲
LEGAL CONSTRAINTS
LIMITATIONS OF USE
The distributor does not assume liability
OTHER CONSTRAINTS
Geodetic Data are in the public domain, not restricted from access or distribution.
SECURITY CONSTRAINTS
CLASSIFICATION unclassified
CLASSIFICATION SYSTEM DOD
ADDITIONAL RESTRICTIONS
none
CONSTRAINTS LIMITATIONS OF USE
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.
Hide Resource Constraints ▲
ARCGIS COORDINATE SYSTEM
TYPE Projected
GEOGRAPHIC COORDINATE REFERENCE GCS_North_American_1983
PROJECTION NAD_1983_Mississippi_TM
COORDINATE REFERENCE DETAILS
PROJECTED COORDINATE SYSTEM
WELL-KNOWN IDENTIFIER 102609
X ORIGIN -5122200
Y ORIGIN -12297100
XY SCALE 450339697.45066422
Z ORIGIN -100000
Z SCALE 10000
M ORIGIN -100000
M SCALE 10000
XY TOLERANCE 0.001
Z TOLERANCE 0.001
M TOLERANCE 0.001
HIGH PRECISION true
LATEST WELL-KNOWN IDENTIFIER 3814
WELL-KNOWN TEXT
PROJCS["NAD_1983_Mississippi_TM",GEOGCS["GCS_North_American_1983",DATUM["D
_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM[
"Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mer cator"],PARAMETER["False_Easting",500000.0],PARAMETER["False_Northing",1300000. 0],PARAMETER["Central_Meridian",- 89.75],PARAMETER["Scale_Factor",0.9998335],PARAMETER["Latitude_Of_Origin",32.5], UNIT["Meter",1.0],AUTHORITY["EPSG",3814]]
REFERENCE SYSTEM IDENTIFIER
VALUE 3814
CODESPACE EPSG
Hide Spatial Reference ▲
VECTOR ►
LEVEL OF TOPOLOGY FOR THIS DATASET geometry only
GEOMETRIC OBJECTS
FEATURE CLASS NAME NGS_Benchmarks_Sep_2017
OBJECT TYPE point
OBJECT COUNT 12480
Hide Vector ▲
INDIRECT SPATIAL REFERENCING
Geodetic Data- horizontal positional datum conversion, use program NADCON (version 2.1) Geodetic Data - vertical positional datum conversion, use program VERTCON (version 2.0) These programs provide indirect spatial reference data and are available from NOAA, National Geodetic Survey at
<http://www.ngs.noaa.gov/PC_PROD/pc_prod.shtml>
VECTOR ►
LEVEL OF TOPOLOGY FOR THIS DATASET geometry only
GEOMETRIC OBJECTS
FEATURE CLASS NAME NGS_Benchmarks_Sep_2017
OBJECT TYPE point
OBJECT COUNT 12480
Hide Vector ▲
ARCGIS FEATURE CLASS PROPERTIES ►
FEATURE CLASS NAME NGS_Benchmarks_Sep_2017
FEATURE TYPE Simple
GEOMETRY TYPE Point
HAS TOPOLOGY FALSE
FEATURE COUNT 12480
SPATIAL INDEX TRUE
LINEAR REFERENCING FALSE
Hide ArcGIS Feature Class Properties ▲
Hide Spatial Data Properties ▲
SCOPE OF QUALITY INFORMATION ►
RESOURCE LEVEL dataset
Hide Scope of quality information ▲
DATA QUALITY REPORT - CONCEPTUAL CONSISTENCY ►
MEASURE DESCRIPTION
FGCS sponsored testing in cooperation with equipment manufacturers and National Institutes of Standards and Technology, Gaithersburg, MD 20850
Hide Data quality report - Conceptual consistency ▲
DATA QUALITY REPORT - COMPLETENESS OMISSION ►
MEASURE DESCRIPTION
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>
Hide Data quality report - Completeness omission ▲
DATA QUALITY REPORT - QUANTITATIVE ATTRIBUTE ACCURACY ►
MEASURE DESCRIPTION
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 TEST RESULTS
VALUE 95 percent confidence level for geodetic quality data.
EVALUATION METHOD
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.
Hide Data quality report - Quantitative attribute accuracy ▲
DATA QUALITY REPORT - ABSOLUTE EXTERNAL POSITIONAL ACCURACY ►
DIMENSION horizontal
MEASURE DESCRIPTION
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.
QUANTITATIVE TEST RESULTS
VALUE .05 meters for highest order of accuracy
EVALUATION METHOD
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>
Hide Data quality report - Absolute external positional accuracy ▲
DATA QUALITY REPORT - ABSOLUTE EXTERNAL POSITIONAL ACCURACY ►
DIMENSION vertical
MEASURE DESCRIPTION
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).
QUANTITATIVE TEST RESULTS
VALUE .05 meter for highest order of accuracy
EVALUATION METHOD
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>
Hide Data quality report - Absolute external positional accuracy ▲
Hide Data Quality ▲
PROCESS STEP ►
WHEN THE PROCESS OCCURRED
INDETERMINATE DATE inapplicable
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.
PROCESS CONTACT
INDIVIDUAL'S NAME NGS Information Services Branch
CONTACT'S POSITION IT Specialist
CONTACT'S ROLE processor
CONTACT INFORMATION ►
PHONE
VOICE 301-713-3242
FAX 301-713-4172
ADDRESS
TYPE both
DELIVERY POINT SSMC2/9152 1315 East-west Highway
CITY Silver Spring ADMINISTRATIVE AREA MD POSTAL CODE 20910 COUNTRY US
E-MAIL ADDRESS ngs.software@noaa.gov
HOURS OF SERVICE
8:30am to 5:00pm EST
CONTACT INSTRUCTIONS
Prefer EMail
Hide Contact information ▲
SOURCE DATA ►
RELATIONSHIP TO THE PROCESS STEP used
SOURCE CITATION ►
ALTERNATE TITLES Geodetic Data
Hide Source citation ▲
Hide Source data ▲
SOURCE DATA ►
RELATIONSHIP TO THE PROCESS STEP produced
SOURCE CITATION ►
ALTERNATE TITLES NOAA, National Geodetic Survey and cooperating organizations.
Hide Source citation ▲
Hide Source data ▲
Hide Process step ▲
SOURCE DATA ►
DESCRIPTION
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.
SOURCE MEDIUM NAME hardcopy—printing on paper
SOURCE CITATION ►
TITLE "Input Formats and Specifications of the National Geodetic Survey Data Base" published by FGCS (formally FGCC)
ALTERNATE TITLES Blue Book
PUBLICATION DATE 2017-09-06
EDITION latest available
PRESENTATION FORMATS hardcopy diagram
FGDC GEOSPATIAL PRESENTATION FORMAT diagram
SERIES
NAME N/A
ISSUE N/A
OTHER CITATION DETAILS
N/A
RESPONSIBLE PARTY
ORGANIZATION'S NAME NOAA, National Geodetic Survey
CONTACT'S ROLE originator
RESPONSIBLE PARTY
ORGANIZATION'S NAME NOAA, National Geodetic Survey
CONTACT'S ROLE publisher
CONTACT INFORMATION ►
ADDRESS
DELIVERY POINT NOAA Campus, Silver Spring, MD
Hide Contact information ▲
RESOURCE LOCATION ONLINE
LOCATION <http://www.ngs.noaa.gov/FGCS/BlueBook/>
Hide Source citation ▲
EXTENT OF THE SOURCE DATA
DESCRIPTION
publication date
TEMPORAL EXTENT
DATE AND TIME 1994-01-01
Hide Source data ▲
Hide Lineage ▲
DISTRIBUTOR ►
CONTACT INFORMATION
INDIVIDUAL'S NAME NGS Information Services Branch
ORGANIZATION'S NAME NOAA, National Geodetic Survey
CONTACT'S POSITION IT Specialist
CONTACT'S ROLE distributor
CONTACT INFORMATION ►
PHONE
VOICE 301-713-3242
FAX 301-713-4172
ADDRESS
TYPE both
DELIVERY POINT SSMC2/9152 1315 East-west Highway
CITY Silver Spring ADMINISTRATIVE AREA MD POSTAL CODE 20910 COUNTRY US
E-MAIL ADDRESS ngs.software@noaa.gov
HOURS OF SERVICE
8:30am to 5:00pm EST
CONTACT INSTRUCTIONS
Prefer EMail
Hide Contact information ▲
AVAILABLE FORMAT
NAME ShapeFile
VERSION 0.3.0; 1999
FILE DECOMPRESSION TECHNIQUE Download options include PC Zip and Unix compressed tar
ORDERING PROCESS
TERMS AND FEES free if you retrieve it yourself
TRANSFER OPTIONS
ONLINE SOURCE
LOCATION www.ngs.noaa.gov/cgi-bin/datasheet.prl
DESCRIPTION Distributed through http://www.ngs.noaa.gov/cgi-bin/datasheet.prl
TRANSFER OPTIONS
ONLINE SOURCE
DESCRIPTION Datasheet Shapefile
Hide Distributor ▲
DISTRIBUTOR ►
CONTACT INFORMATION
INDIVIDUAL'S NAME Steve Walker
ORGANIZATION'S NAME MARIS
CONTACT'S POSITION GIS Operations Manager
CONTACT'S ROLE distributor
CONTACT INFORMATION ►
ADDRESS TYPE
E-MAIL ADDRESS swalker@mississippi.edu
ONLINE RESOURCE
LOCATION www.maris.state.ms.us/stsatewide/
Hide Contact information ▲
Hide Distributor ▲
DISTRIBUTION FORMAT
NAME Shapefile
VERSION ArcGIS 10.4
TRANSFER OPTIONS
TRANSFER SIZE 0.333
ONLINE SOURCE
LOCATION http://www.ngs.noaa.gov/cgi-bin/datasheet.prl
Hide Distribution ▲
DETAILS FOR OBJECT NGS_Benchmarks_Sep_2017 ►
TYPE Feature Class
ROW COUNT 12480
FIELD FID ►
ALIAS FID
DATA TYPE OID
WIDTH 4
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Internal feature number.
DESCRIPTION SOURCE
Esri
DESCRIPTION OF VALUES
Sequential unique whole numbers that are automatically generated.
Hide Field FID ▲
FIELD Shape ►
ALIAS Shape
DATA TYPE Geometry
WIDTH 0
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Feature geometry.
DESCRIPTION SOURCE
Esri
DESCRIPTION OF VALUES
Coordinates defining the features.
Hide Field Shape ▲
FIELD FeatureId ►
ALIAS FeatureId
DATA TYPE Integer
WIDTH 5
PRECISION 5
SCALE 0
Hide Field FeatureId ▲
FIELD DATA_DATE ►
ALIAS DATA_DATE
DATA TYPE String
WIDTH 8
PRECISION 0
SCALE 0
FIELD DESCRIPTION
The date when this information was retrieved from the NGS database.
DESCRIPTION SOURCE
NGS
Hide Field DATA_DATE ▲
FIELD DATA_SRCE ►
ALIAS DATA_SRCE
DATA TYPE String
WIDTH 57
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Data Source where the information for the mark came from. You should use this link to obtain a full datasheet for the mark or obtain the datasheets from
<http://www.ngs.noaa.gov/cgi-bin/datasheet.prl> if you intend to use the data for survey control.
DESCRIPTION SOURCE
NGS
Hide Field DATA_SRCE ▲
FIELD DEC_LONG ►
ALIAS DEC_LONG
DATA TYPE String
WIDTH 15
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Decimal equivalent of the LONGITUDE Always displayed to 10 decimal places, but you should see POS_SRCE and POS_ORDER to determine the true accuracy.
DESCRIPTION SOURCE
NGS
Hide Field DEC_LONG ▲
FIELD DEC_LAT ►
ALIAS DEC_LAT
DATA TYPE String
WIDTH 13
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Decimal equivalent of the LATITUDE PID- Permanent Identifier assigned by NGS to each mark
DESCRIPTION SOURCE
NGS
Hide Field DEC_LAT ▲
FIELD PID ►
ALIAS PID
DATA TYPE String
WIDTH 6
PRECISION 0
SCALE 0
FIELD DESCRIPTION
PID- Permanent Identifier assigned by NGS to each mark
DESCRIPTION SOURCE
NGS
Hide Field PID ▲
FIELD NAME ►
ALIAS NAME
DATA TYPE String
WIDTH 40
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Station Name (a.k.a. Designation)
DESCRIPTION SOURCE
NGS
Hide Field NAME ▲
FIELD STATE ►
ALIAS STATE
DATA TYPE String
WIDTH 2
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Mississippi
DESCRIPTION SOURCE
NGS
Hide Field STATE ▲
FIELD COUNTY ►
ALIAS COUNTY
DATA TYPE String
WIDTH 26
PRECISION 0
SCALE 0
FIELD DESCRIPTION
County of location
DESCRIPTION SOURCE
NGS
Hide Field COUNTY ▲
FIELD QUAD ►
ALIAS QUAD
DATA TYPE String
WIDTH 40
PRECISION 0
SCALE 0
FIELD DESCRIPTION
USGS Quad Name of Location
DESCRIPTION SOURCE
NGS
Hide Field QUAD ▲
FIELD LATITUDE ►
ALIAS LATITUDE
DATA TYPE String
WIDTH 17
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Latitude in Deg-Min-Sec format
DESCRIPTION SOURCE
NGS
Hide Field LATITUDE ▲
FIELD LONGITUDE ►
ALIAS LONGITUDE
DATA TYPE String
WIDTH 18
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Longitude in Deg-Min-Sec format
DESCRIPTION SOURCE
NGS
Hide Field LONGITUDE ▲
FIELD POS_DATUM ►
ALIAS POS_DATUM
DATA TYPE String
WIDTH 6
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Datum of the LATITUDE,LONGITUDE Should always be NAD83
DESCRIPTION SOURCE
NGS
Hide Field POS_DATUM ▲
FIELD DATUM_TAG ►
ALIAS DATUM_TAG
DATA TYPE String
WIDTH 6
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Datum Tag of the LATITUDE,LONGITUDE NAD83 (1986) indicates positions on the NAD83 datum for the North American Adjustment, completed in 1986. NAD83 (nnnn) indicates positions on the NAD83 datum for the North American Adjustment, but readjusted to a State High Accuracy Reference Network (HARN) on the date shown in (nnnn). NAD83 (CORS) indicates positions which are part of the CORS network
DESCRIPTION SOURCE
NGS
Hide Field DATUM_TAG ▲
FIELD POS_SRCE ►
ALIAS POS_SRCE
DATA TYPE String
WIDTH 12
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Position Source for the LATITUDE,LONGITUDE ADJUSTED = Least squares adjustment. (Lat,Lon Rounded to 5 decimal places.) HD_HELD1 = Differentially corrected hand held GPS observations. (Lat,Lon Rounded to 2 decimal places.) HD_HELD2 = Autonomous hand held GPS observations. (Lat,Lon Rounded to 1 decimal places.) SCALED = Scaled from a topographic map. (Lat,Lon Rounded to 0 decimal places.)
DESCRIPTION SOURCE
NGS
Hide Field POS_SRCE ▲
FIELD ELEVATION ►
ALIAS ELEVATION
DATA TYPE String
WIDTH 9
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Present if available. The Orthometric Height in METERS indicating the height above the Geoid.
DESCRIPTION SOURCE
NGS
Hide Field ELEVATION ▲
FIELD ELEV_DATUM ►
ALIAS ELEV_DATUM
DATA TYPE String
WIDTH 12
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Datum of the ELEVATION
DESCRIPTION SOURCE
NGS
Hide Field ELEV_DATUM ▲
FIELD ELEV_SRCE ►
ALIAS ELEV_SRCE
DATA TYPE String
WIDTH 12
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Direct Digital Output from Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) ADJ UNCH = Manually Entered (and NOT verified) Output of Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) POSTED = Pre-1991 Precise Leveling Adjusted to the NAVD 88 Network After Completion of the NAVD 88 General Adjustment of 1991. (Rounded to 3 decimal places.) READJUST = Precise Leveling Readjusted as Required by Crustal Motion or Other Cause. (Rounded to 2 decimal places.) N HEIGHT = Computed from Precise Leveling Connected at Only One Published Bench Mark. (Rounded to 2 decimal places.) RESET = Reset Computation of Precise Leveling. (Rounded to 2 decimal places.) COMPUTED =
Computed from Precise Leveling Using Non-rigorous Adjustment Technique. (Rounded to 2 decimal places.) LEVELING = Precise Leveling Performed by Horizontal Field Party. (Rounded to 2 decimal places.) H LEVEL = Level between control points not connected to bench mark. (Rounded to 1 decimal places.) GPS OBS = Computed from GPS Observations. (Rounded to 1 decimal places.) VERT ANG = Computed from Vertical Angle Observations. (Rounded to 1 decimal place; If No Check, to 0 decimal places.) SCALED = Scaled from a Topographic Map. (Rounded to 0 decimal places.) U HEIGHT
= Unvalidated height from precise leveling connected at only one NSRS point. (Rounded to 2 decimal places.) VERTCON = The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height. (Rounded to 0 decimal places.)
DESCRIPTION SOURCE
NGS
Hide Field ELEV_SRCE ▲
FIELD ELLIP_HT ►
ALIAS ELLIP_HT
DATA TYPE String
WIDTH 9
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Present if available. The ellipsoid height in METERS referenced to GRS80 ellipsoid.
DESCRIPTION SOURCE
NGS
Hide Field ELLIP_HT ▲
FIELD ELLIP_SRCE ►
ALIAS ELLIP_SRCE
DATA TYPE String
WIDTH 12
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Ellipsoid Ht Source for the ELLIP_HT Should always be GPS_OBS when present.
DESCRIPTION SOURCE
NGS
Hide Field ELLIP_SRCE ▲
FIELD POS_ORDER ►
ALIAS POS_ORDER
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Order of accuracy for the LATITUDE,LONGITUDE Should be one of the following- A,B,1,2,3 Order and class for Orders 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication "Standards and Specifications for Geodetic Control Networks". In addition- Order A stations have a relative accuracy of 5 mm +/- 1- 10,000,000 relative to other A-order stations. Order B stations have a relative accuracy of 8 mm +/- 1- 1,000,000 relative to other A- and B-order stations.
DESCRIPTION SOURCE
NGS
Hide Field POS_ORDER ▲
FIELD POS_CHECK ►
ALIAS POS_CHECK
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Y=Observational Check was made for the position, N=NO Observational Check was made for the positions
DESCRIPTION SOURCE
NGS
Hide Field POS_CHECK ▲
FIELD ELEV_ORDER ►
ALIAS ELEV_ORDER
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Order of accuracy for the ELEVATION Should be 1,2, or 3 for Vertical Control Stations. Will be blank for stations used for Horizontal Control only. Also see attribute DIST_RATE which is used for some vertical control stations. Elevation order and class for 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication "Standards and Specifications for Geodetic Control Networks". In addition- Vertical control which were determined only for the purpose of supplying a height for Horizontal Distance Reductions are assigned an order of 3. Class 0 is used for special
cases of orthometric vertical control as follows- Vertical Order/Class Tolerance Factor --
------------------ ---------------- 1 class 0 2.0 mm or less 2 class 0 8.4 mm or less 3
class 0 12.0 mm or less
DESCRIPTION SOURCE
NGS
Hide Field ELEV_ORDER ▲
FIELD ELEV_CLASS ►
ALIAS ELEV_CLASS
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Should be 0, 1, or 2 See details under ELEV_ORDER
DESCRIPTION SOURCE
NGS
Hide Field ELEV_CLASS ▲
FIELD ELEV_CHECK ►
ALIAS ELEV_CHECK
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Y=Observational Check was made for the orthometric height, N=NO Observational Check was made for the orthometric heights VERTCONED- Y=Orthometric Height was determined by applying VERTCON to an old NGVD 29 height. N=Orthometric Height determined by observations.
DESCRIPTION SOURCE
NGS
Hide Field ELEV_CHECK ▲
FIELD DIST_RATE ►
ALIAS DIST_RATE
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Distribution rate for POSTED and READJUSTED benchmarks which do not have an Order and Class are as follows "Posted bench marks" are vertical control points in the NGS data base which were excluded from the NAVD 88 general adjustment. Some of the bench marks were excluded due to large adjustment residuals, possibly caused by vertical movement of the bench marks during the time interval between different leveling epochs. Adjusted NAVD 88 are computed for posted bench marks by supplemental adjustments. A range of mean distribution rate corrections is listed for each posted bench mark in the data portion of the publication. A summary table of the mean distribution rates and their codes is listed below. The mean distribution rate corrections which were applied to the original leveling observations is a good indication of the usefulness of the posted bench marks' adjusted NAVD 88 heights. Distribution Distribution Rate Code Rate Correction "a" 0.0 thru 1.0
mm/km "b" 1.1 thru 2.0 " "c" 2.1 thru 3.0 " "d" 3.1 thru 4.0 " "e" 4.1 thru 8.0 " "f" greater than 8.0 mm/km POSTED BENCH MARKS SHOULD BE USED WITH CAUTION.
As is the case for all leveling projects, the mandatory FGCS check leveling two-mark or three-mark tie procedure will usually detect any isolated movement (or other problem) at an individual bench mark. Of course, regional movement affecting all the marks equally is not detected by the two- or three-mark tie procedure.
DESCRIPTION SOURCE
NGS
Hide Field DIST_RATE ▲
FIELD ELLP_ORDER ►
ALIAS ELLP_ORDER
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Order of accuracy for the ELLIP_HT Should be 1,2,3,4, or 5 if present. The following ellipsoid height order and class relative accuracy standards have not yet been adopted by the Federal Geodetic Control Subcommittee, but are currently in use by NGS- Ellipsoid Height Maximum Height Classification Difference Accuracy ------------------ ---
---------------- 1 class 1 0.5 (mm)/sqrt(km) 1 class 2 0.7 2 class 1 1.0 2 class 2 1.3 3
class 1 2.0 3 class 2 3.0 4 class 1 6.0 4 class 2 15.0 5 class 1 30.0 5 class 2 60.0 The ellipsoid height difference accuracy (b) is computed from a a minimally constrained correctly weighted least squares adjustment by- b = s / sqrt(d) where b = height difference accuracy s = propagated standard deviation of ellipsoid height difference in millimeters between control points obtained from the least squares adjustment. d = horizontal distance between control points in kilometers
DESCRIPTION SOURCE
NGS
Hide Field ELLP_ORDER ▲
FIELD ELLP_CLASS ►
ALIAS ELLP_CLASS
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Class of accuracy for ELLIP_HT Should be 1 or 2 See details under ELLP_ORDER
DESCRIPTION SOURCE
NGS
Hide Field ELLP_CLASS ▲
FIELD FIRST_RECV ►
ALIAS FIRST_RECV
DATA TYPE String
WIDTH 8
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Date when the station was first monumented or in the case of landmarks, first observed.
DESCRIPTION SOURCE
NGS
Hide Field FIRST_RECV ▲
FIELD LAST_RECV ►
ALIAS LAST_RECV
DATA TYPE String
WIDTH 8
PRECISION 0
SCALE 0
Hide Field LAST_RECV ▲
FIELD LAST_COND ►
ALIAS LAST_COND
DATA TYPE String
WIDTH 16
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Last recovered condition of the mark. Should be one of the following- MONUMENTED FIRST OBSERVED GOOD POOR MARK NOT FOUND SEE DESCRIPTION DESTROYED
DESCRIPTION SOURCE
NGS
Hide Field LAST_COND ▲
FIELD LAST_RECBY ►
ALIAS LAST_RECBY
DATA TYPE String
WIDTH 6
PRECISION 0
SCALE 0
FIELD DESCRIPTION
Agency who reported the last condition of the mark.
DESCRIPTION SOURCE
NGS
Hide Field LAST_RECBY ▲
FIELD SAT_USE ►
ALIAS SAT_USE
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
Hide Field SAT_USE ▲
FIELD SAT_DATE ►
ALIAS SAT_DATE
DATA TYPE String
WIDTH 8
PRECISION 0
SCALE 0
Hide Field SAT_DATE ▲
FIELD STABILITY ►
ALIAS STABILITY
DATA TYPE String
WIDTH 1
PRECISION 0
SCALE 0
FIELD DESCRIPTION
The stability of the mark may have 1 of 4 codes as indicated below- A = MOST RELIABLE AND EXPECTED TO HOLD POSITION/ELEVATION WELL B = PROBABLY HOLD POSITION/ELEVATION WELL C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO SURFACE MOTION - E.G. FROST HEAVE, ETC D = MARK OF QUESTIONABLE OR UNKNOWN STABILITY
DESCRIPTION SOURCE
NGS
Hide Field STABILITY ▲
Hide Details for object NGS_Benchmarks_Sep_2017 ▲
OVERVIEW DESCRIPTION ►
ENTITY AND ATTRIBUTE OVERVIEW
The current attributes and their meaning are shown below. #FeatureId Temporary unique ID assigned to this station. DATA_DATE- The date when this information was retrieved from the NGS database. DATA_SRCE- Data Source where the information for the mark came from. You should use this link to obtain a full datasheet for the mark or obtain the datasheets from <http://www.ngs.noaa.gov/cgi-bin/datasheet.prl> if you intend to use the data for survey control. DEC_LONG- Decimal equivalent of the LONGITUDE Always displayed to 10 decimal places, but you should see POS_SRCE and POS_ORDER to determine the true accuracy. DEC_LAT- Decimal equivalent of the LATITUDE PID- Permanent Identifier assigned by NGS to each mark NAME- Station Name (a.k.a. Designation) STATE- State Code COUNTY- County Name QUAD- USGS Topographic Quad Map Name LATITUDE- Latitude in Deg-Min-Sec format LONGITUDE- Longitude in Deg-Min-Sec format POS_DATUM- Datum of the LATITUDE,LONGITUDE Should always be NAD83 DATUM_TAG- Datum Tag of the LATITUDE,LONGITUDE NAD83 (1986) indicates positions on the NAD83 datum for the North American Adjustment, completed in 1986. NAD83 (nnnn) indicates positions on the NAD83 datum for the North American Adjustment, but readjusted to a State High Accuracy
Reference Network (HARN) on the date shown in (nnnn). NAD83 (CORS) indicates positions which are part of the CORS network. POS_SRCE- Position Source for the LATITUDE,LONGITUDE ADJUSTED = Least squares adjustment. (Lat,Lon Rounded to 5 decimal places.) HD_HELD1 = Differentially corrected hand held GPS observations. (Lat,Lon Rounded to 2 decimal places.) HD_HELD2 = Autonomous hand held GPS observations. (Lat,Lon Rounded to 1 decimal places.) SCALED = Scaled from a topographic map. (Lat,Lon Rounded to 0 decimal places.) ELEVATION- Present if available. The Orthometric Height in METERS indicating the height above the Geoid.
ELEV_DATUM- Datum of the ELEVATION ELEV_SRCE- Elevation Source for the ELEVATION ADJUSTED = Direct Digital Output from Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) ADJ UNCH = Manually Entered (and NOT verified) Output of Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) POSTED = Pre-1991 Precise Leveling Adjusted to the NAVD 88 Network After Completion of the NAVD 88 General Adjustment of 1991. (Rounded to 3 decimal places.) READJUST = Precise Leveling Readjusted as Required by Crustal Motion or Other Cause. (Rounded to 2 decimal places.) N HEIGHT = Computed from Precise Leveling Connected at Only One Published Bench Mark. (Rounded to 2 decimal places.) RESET = Reset Computation of Precise Leveling. (Rounded to 2 decimal places.) COMPUTED = Computed from Precise Leveling Using Non-rigorous Adjustment Technique. (Rounded to 2 decimal places.) LEVELING = Precise Leveling Performed by Horizontal Field Party. (Rounded to 2 decimal places.) H LEVEL = Level between control points not connected to bench mark. (Rounded to 1 decimal places.) GPS OBS
= Computed from GPS Observations. (Rounded to 1 decimal places.) VERT ANG = Computed from Vertical Angle Observations. (Rounded to 1 decimal place; If No Check, to 0 decimal places.) SCALED = Scaled from a Topographic Map. (Rounded to 0 decimal places.) U HEIGHT = Unvalidated height from precise leveling connected at only one NSRS point. (Rounded to 2 decimal places.) VERTCON = The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height. (Rounded to 0 decimal places.) ELLIP_HT- Present if available. The ellipsoid height in METERS referenced to GRS80 ellipsoid. ELLIP_SRCE- Ellipsoid Ht Source for the ELLIP_HT Should always be GPS_OBS when present. POS_ORDER- Order of accuracy for the LATITUDE,LONGITUDE Should be one of the following- A,B,1,2,3 Order and class for Orders 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication "Standards and Specifications for Geodetic Control Networks". In addition- Order A stations have a relative accuracy of 5 mm +/- 1-10,000,000 relative to other A-order stations. Order B stations have a relative accuracy of 8 mm +/- 1- 1,000,000 relative to other A- and B-order stations. POS_CHECK- Y=Observational Check was made for the position, N=NO Observational Check was made for the positions ELEV_ORDER- Order of accuracy for the ELEVATION Should be 1,2, or 3 for Vertical Control Stations. Will be blank for stations used for Horizontal Control only. Also see attribute DIST_RATE which is used for some vertical control stations. Elevation order and class for 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication "Standards and Specifications for Geodetic Control Networks". In addition- Vertical control which were determined only for the purpose of supplying a height for Horizontal Distance Reductions are assigned an order of 3. Class 0 is used for special
cases of orthometric vertical control as follows- Vertical Order/Class Tolerance Factor --
------------------ ---------------- 1 class 0 2.0 mm or less 2 class 0 8.4 mm or less 3
class 0 12.0 mm or less ELEV_CLASS- Should be 0, 1, or 2 See details under ELEV_ORDER ELEV_CHECK- Y=Observational Check was made for the orthometric height, N=NO Observational Check was made for the orthometric heights VERTCONED- Y=Orthometric Height was determined by applying VERTCON to an old NGVD 29 height. N=Orthometric Height determined by observations. DIST_RATE- Distribution rate for POSTED and READJUSTED benchmarks which do not have an Order and Class are as follows "Posted bench marks" are vertical control points in the NGS data base which were excluded from the NAVD 88 general adjustment. Some of the bench marks were excluded due to large adjustment residuals, possibly caused by vertical
movement of the bench marks during the time interval between different leveling epochs. Adjusted NAVD 88 are computed for posted bench marks by supplemental adjustments. A range of mean distribution rate corrections is listed for each posted bench mark in the data portion of the publication. A summary table of the mean distribution rates and their codes is listed below. The mean distribution rate corrections which were applied to the original leveling observations is a good indication of the usefulness of the posted bench marks' adjusted NAVD 88 heights. Distribution Distribution Rate Code Rate Correction "a" 0.0 thru 1.0
mm/km "b" 1.1 thru 2.0 " "c" 2.1 thru 3.0 " "d" 3.1 thru 4.0 " "e" 4.1 thru 8.0 " "f" greater than 8.0 mm/km POSTED BENCH MARKS SHOULD BE USED WITH CAUTION.
As is the case for all leveling projects, the mandatory FGCS check leveling two-mark or three-mark tie procedure will usually detect any isolated movement (or other problem) at an individual bench mark. Of course, regional movement affecting all the marks equally is not detected by the two- or three-mark tie procedure. ELLP_ORDER- Order of accuracy for the ELLIP_HT Should be 1,2,3,4, or 5 if present. The following ellipsoid height order and class relative accuracy standards have not yet been adopted by the Federal Geodetic Control Subcommittee, but are currently in use by NGS- Ellipsoid Height Maximum Height Classification Difference Accuracy ------------------ -------------
------ 1 class 1 0.5 (mm)/sqrt(km) 1 class 2 0.7 2 class 1 1.0 2 class 2 1.3 3 class 1
2.0 3 class 2 3.0 4 class 1 6.0 4 class 2 15.0 5 class 1 30.0 5 class 2 60.0 The ellipsoid height difference accuracy (b) is computed from a a minimally constrained correctly weighted least squares adjustment by- b = s / sqrt(d) where b = height difference accuracy s = propagated standard deviation of ellipsoid height difference in millimeters between control points obtained from the least squares adjustment. d = horizontal distance between control points in kilometers ELLP_class- Class of accuracy for ELLIP_HT Should be 1 or 2 See details under ELLP_ORDER FIRST_RECV- Date when the station was first monumented or in the case of landmarks, first observed. LAST_RECV- Date when the station was last recovered. LAST_COND- Last recovered condition of the mark. Should be one of the following- MONUMENTED FIRST OBSERVED GOOD POOR MARK NOT FOUND SEE DESCRIPTION DESTROYED LAST_RECBY- Agency who reported the last condition of the mark. STABILITY- The stability of the mark may have 1 of 4 codes as indicated below- A = MOST RELIABLE AND EXPECTED TO HOLD POSITION/ELEVATION WELL B = PROBABLY HOLD POSITION/ELEVATION WELL C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO SURFACE MOTION - E.G. FROST HEAVE, ETC D = MARK OF QUESTIONABLE OR UNKNOWN STABILITY
ENTITY AND ATTRIBUTE DETAIL CITATION
All values were obtained from the NGA Datasheet available at
<http://www.ngs.noaa.gov/cgi-bin/datasheet.prl>
Hide Overview Description ▲
Hide Fields ▲
METADATA LANGUAGE English (UNITED STATES)
METADATA CHARACTER SET utf8 - 8 bit UCS Transfer Format
SCOPE OF THE DATA DESCRIBED BY THE METADATA dataset
SCOPE NAME * dataset
ARCGIS METADATA PROPERTIES
METADATA FORMAT ArcGIS 1.0
METADATA STYLE ISO 19139 Metadata Implementation Specification
STANDARD OR PROFILE USED TO EDIT METADATA ISO19139
CREATED IN ARCGIS FOR THE ITEM 2017-09-13 14:00:19
LAST MODIFIED IN ARCGIS FOR THE ITEM 2017-09-13 14:41:36
AUTOMATIC UPDATES
HAVE BEEN PERFORMED Yes
LAST UPDATE 2017-09-13 14:20:27
Hide Metadata Details ▲
METADATA CONTACT
INDIVIDUAL'S NAME NGS Information Services Branch ORGANIZATION'S NAME NOAA, National Geodetic Survey CONTACT'S POSITION IT Specialist
CONTACT'S ROLE point of contact
CONTACT INFORMATION ►
PHONE
VOICE 301-713-3242
FAX 301-713-4172
ADDRESS
TYPE both
DELIVERY POINT SSMC2/9152 1315 East-west Highway
CITY Silver Spring ADMINISTRATIVE AREA MD POSTAL CODE 20910 COUNTRY US
E-MAIL ADDRESS ngs.software@noaa.gov
HOURS OF SERVICE
8:30am to 5:00pm EST
CONTACT INSTRUCTIONS
Prefer EMail
Hide Contact information ▲
Hide Metadata Contacts ▲
LEGAL CONSTRAINTS
ACCESS CONSTRAINTS other restrictions
OTHER CONSTRAINTS
Geodetic Data are in the public domain, not restricted from access or distribution.
SECURITY CONSTRAINTS
CLASSIFICATION unclassified
CLASSIFICATION SYSTEM DOD
ADDITIONAL RESTRICTIONS
none
CONSTRAINTS LIMITATIONS OF USE
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.
Hide Metadata Constraints ▲
THUMBNAIL
THUMBNAIL TYPE JPG
Hide Thumbnail and Enclosures ▲
FGDC Metadata (read-only) ▼
DETAILED DESCRIPTION ENTITY TYPE
ENTITY TYPE LABEL NGS_Benchmarks_Sep_2017
ATTRIBUTE
ATTRIBUTE LABEL FID
ATTRIBUTE DEFINITION
Internal feature number.
ATTRIBUTE DEFINITION SOURCE Esri
ATTRIBUTE DOMAIN VALUES UNREPRESENTABLE DOMAIN
Sequential unique whole numbers that are automatically generated.
ATTRIBUTE
ATTRIBUTE LABEL Shape
ATTRIBUTE DEFINITION
Feature geometry.
ATTRIBUTE DEFINITION SOURCE Esri
ATTRIBUTE DOMAIN VALUES UNREPRESENTABLE DOMAIN
Coordinates defining the features.
ATTRIBUTE
ATTRIBUTE LABEL FeatureId
ATTRIBUTE
ATTRIBUTE LABEL DATA_DATE
ATTRIBUTE DEFINITION
The date when this information was retrieved from the NGS database.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL DATA_SRCE
ATTRIBUTE DEFINITION
Data Source where the information for the mark came from. You should use this link to obtain a full datasheet for the mark or obtain the datasheets from
<http://www.ngs.noaa.gov/cgi-bin/datasheet.prl> if you intend to use the data for survey control.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL DEC_LONG
ATTRIBUTE DEFINITION
Decimal equivalent of the LONGITUDE Always displayed to 10 decimal places, but you should see POS_SRCE and POS_ORDER to determine the true accuracy.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL DEC_LAT ATTRIBUTE DEFINITION
Decimal equivalent of the LATITUDE PID- Permanent Identifier assigned by NGS to each mark
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL PID ATTRIBUTE DEFINITION
PID- Permanent Identifier assigned by NGS to each mark
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL NAME ATTRIBUTE DEFINITION
Station Name (a.k.a. Designation)
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL STATE ATTRIBUTE DEFINITION
Mississippi
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL COUNTY ATTRIBUTE DEFINITION
County of location
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL QUAD ATTRIBUTE DEFINITION
USGS Quad Name of Location
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL LATITUDE ATTRIBUTE DEFINITION
Latitude in Deg-Min-Sec format
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL LONGITUDE ATTRIBUTE DEFINITION
Longitude in Deg-Min-Sec format
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL POS_DATUM ATTRIBUTE DEFINITION
Datum of the LATITUDE,LONGITUDE Should always be NAD83
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL DATUM_TAG ATTRIBUTE DEFINITION
- Datum Tag of the LATITUDE,LONGITUDE NAD83 (1986) indicates positions on the NAD83 datum for the North American Adjustment, completed in 1986. NAD83 (nnnn) indicates positions on the NAD83 datum for the North American Adjustment, but readjusted to a State High Accuracy Reference Network (HARN) on the date shown in (nnnn). NAD83 (CORS) indicates positions which are part of the CORS network
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL POS_SRCE ATTRIBUTE DEFINITION
Position Source for the LATITUDE,LONGITUDE ADJUSTED = Least squares adjustment. (Lat,Lon Rounded to 5 decimal places.) HD_HELD1 = Differentially corrected hand held GPS observations. (Lat,Lon Rounded to 2 decimal places.) HD_HELD2 = Autonomous hand held GPS observations. (Lat,Lon Rounded to 1 decimal places.) SCALED = Scaled from a topographic map. (Lat,Lon Rounded to 0 decimal places.)
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL ELEVATION ATTRIBUTE DEFINITION
- Present if available. The Orthometric Height in METERS indicating the height above the Geoid.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE ATTRIBUTE LABEL ELEV_DATUM ATTRIBUTE DEFINITION
Datum of the ELEVATION
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELEV_SRCE
ATTRIBUTE DEFINITION
Direct Digital Output from Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) ADJ UNCH = Manually Entered (and NOT verified) Output of Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) POSTED = Pre-1991 Precise Leveling Adjusted to the NAVD 88 Network After Completion of the NAVD 88 General Adjustment of 1991. (Rounded to 3 decimal places.) READJUST = Precise Leveling Readjusted as Required by Crustal Motion or Other Cause. (Rounded to 2 decimal places.) N HEIGHT = Computed from Precise Leveling Connected at Only One Published Bench Mark. (Rounded to 2 decimal places.) RESET = Reset Computation of Precise Leveling. (Rounded to 2 decimal places.) COMPUTED =
Computed from Precise Leveling Using Non-rigorous Adjustment Technique. (Rounded to 2 decimal places.) LEVELING = Precise Leveling Performed by Horizontal Field Party. (Rounded to 2 decimal places.) H LEVEL = Level between control points not connected to bench mark. (Rounded to 1 decimal places.) GPS OBS = Computed from GPS Observations. (Rounded to 1 decimal places.) VERT ANG = Computed from Vertical Angle Observations. (Rounded to 1 decimal place; If No Check, to 0 decimal places.) SCALED = Scaled from a Topographic Map. (Rounded to 0 decimal places.) U HEIGHT
= Unvalidated height from precise leveling connected at only one NSRS point. (Rounded to 2 decimal places.) VERTCON = The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height. (Rounded to 0 decimal places.)
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELLIP_HT
ATTRIBUTE DEFINITION
Present if available. The ellipsoid height in METERS referenced to GRS80 ellipsoid.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELLIP_SRCE
ATTRIBUTE DEFINITION
Ellipsoid Ht Source for the ELLIP_HT Should always be GPS_OBS when present.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL POS_ORDER
ATTRIBUTE DEFINITION
- Order of accuracy for the LATITUDE,LONGITUDE Should be one of the following- A,B,1,2,3 Order and class for Orders 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication "Standards and Specifications for Geodetic Control Networks". In addition- Order A stations have a relative accuracy of 5 mm +/- 1- 10,000,000 relative to other A-order stations. Order B stations have a relative accuracy of 8 mm +/- 1- 1,000,000 relative to other A- and B-order stations.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL POS_CHECK
ATTRIBUTE DEFINITION
Y=Observational Check was made for the position, N=NO Observational Check was made for the positions
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELEV_ORDER
ATTRIBUTE DEFINITION
Order of accuracy for the ELEVATION Should be 1,2, or 3 for Vertical Control Stations. Will be blank for stations used for Horizontal Control only. Also see attribute
DIST_RATE which is used for some vertical control stations. Elevation order and class for 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication "Standards and Specifications for Geodetic Control Networks". In addition- Vertical control which were determined only for the purpose of supplying a height for Horizontal Distance Reductions are assigned an order of 3. Class 0 is used for special
cases of orthometric vertical control as follows- Vertical Order/Class Tolerance Factor --
------------------ ---------------- 1 class 0 2.0 mm or less 2 class 0 8.4 mm or less 3
class 0 12.0 mm or less
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELEV_CLASS
ATTRIBUTE DEFINITION
Should be 0, 1, or 2 See details under ELEV_ORDER
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELEV_CHECK
ATTRIBUTE DEFINITION
- Y=Observational Check was made for the orthometric height, N=NO Observational Check was made for the orthometric heights VERTCONED- Y=Orthometric Height was determined by applying VERTCON to an old NGVD 29 height. N=Orthometric Height determined by observations.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL DIST_RATE
ATTRIBUTE DEFINITION
Distribution rate for POSTED and READJUSTED benchmarks which do not have an Order and Class are as follows "Posted bench marks" are vertical control points in the NGS data base which were excluded from the NAVD 88 general adjustment. Some of the bench marks were excluded due to large adjustment residuals, possibly caused by vertical movement of the bench marks during the time interval between different leveling epochs. Adjusted NAVD 88 are computed for posted bench marks by supplemental adjustments. A range of mean distribution rate corrections is listed for each posted bench mark in the data portion of the publication. A summary table of the mean distribution rates and their codes is listed below. The mean distribution rate corrections which were applied to the original leveling observations is a good indication of the usefulness of the posted bench marks' adjusted NAVD 88 heights. Distribution Distribution Rate Code Rate Correction "a" 0.0 thru 1.0
mm/km "b" 1.1 thru 2.0 " "c" 2.1 thru 3.0 " "d" 3.1 thru 4.0 " "e" 4.1 thru 8.0 " "f" greater than 8.0 mm/km POSTED BENCH MARKS SHOULD BE USED WITH CAUTION.
As is the case for all leveling projects, the mandatory FGCS check leveling two-mark or three-mark tie procedure will usually detect any isolated movement (or other problem) at an individual bench mark. Of course, regional movement affecting all the marks equally is not detected by the two- or three-mark tie procedure.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELLP_ORDER
ATTRIBUTE DEFINITION
- Order of accuracy for the ELLIP_HT Should be 1,2,3,4, or 5 if present. The following ellipsoid height order and class relative accuracy standards have not yet been adopted by the Federal Geodetic Control Subcommittee, but are currently in use by NGS- Ellipsoid Height Maximum Height Classification Difference Accuracy ------------------ ---
---------------- 1 class 1 0.5 (mm)/sqrt(km) 1 class 2 0.7 2 class 1 1.0 2 class 2 1.3 3
class 1 2.0 3 class 2 3.0 4 class 1 6.0 4 class 2 15.0 5 class 1 30.0 5 class 2 60.0 The ellipsoid height difference accuracy (b) is computed from a a minimally constrained correctly weighted least squares adjustment by- b = s / sqrt(d) where b = height difference accuracy s = propagated standard deviation of ellipsoid height difference in millimeters between control points obtained from the least squares adjustment. d = horizontal distance between control points in kilometers
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL ELLP_CLASS
ATTRIBUTE DEFINITION
Class of accuracy for ELLIP_HT Should be 1 or 2 See details under ELLP_ORDER
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL FIRST_RECV
ATTRIBUTE DEFINITION
Date when the station was first monumented or in the case of landmarks, first observed.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE LABEL LAST_RECV
ATTRIBUTE
ATTRIBUTE LABEL LAST_COND
ATTRIBUTE DEFINITION
ATTRIBUTE
Last recovered condition of the mark. Should be one of the following- MONUMENTED FIRST OBSERVED GOOD POOR MARK NOT FOUND SEE DESCRIPTION DESTROYED
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE LABEL LAST_RECBY
ATTRIBUTE DEFINITION
Agency who reported the last condition of the mark.
ATTRIBUTE DEFINITION SOURCE NGS
ATTRIBUTE
ATTRIBUTE LABEL SAT_USE
ATTRIBUTE
ATTRIBUTE LABEL SAT_DATE
ATTRIBUTE
ATTRIBUTE LABEL STABILITY
ATTRIBUTE DEFINITION
ATTRIBUTE
The stability of the mark may have 1 of 4 codes as indicated below- A = MOST RELIABLE AND EXPECTED TO HOLD POSITION/ELEVATION WELL B = PROBABLY HOLD POSITION/ELEVATION WELL C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO SURFACE MOTION - E.G. FROST HEAVE, ETC D = MARK OF QUESTIONABLE OR UNKNOWN STABILITY
ATTRIBUTE DEFINITION SOURCE NGS
OVERVIEW DESCRIPTION
ENTITY AND ATTRIBUTE OVERVIEW
The current attributes and their meaning are shown below. #FeatureId Temporary unique ID assigned to this station. DATA_DATE- The date when this information was
retrieved from the NGS database. DATA_SRCE- Data Source where the information for the mark came from. You should use this link to obtain a full datasheet for the mark or obtain the datasheets from <http://www.ngs.noaa.gov/cgi-bin/datasheet.prl> if you intend to use the data for survey control. DEC_LONG- Decimal equivalent of the LONGITUDE Always displayed to 10 decimal places, but you should see POS_SRCE and POS_ORDER to determine the true accuracy. DEC_LAT- Decimal equivalent of the LATITUDE PID- Permanent Identifier assigned by NGS to each mark NAME- Station Name (a.k.a. Designation) STATE- State Code COUNTY- County Name QUAD- USGS Topographic Quad Map Name LATITUDE- Latitude in Deg-Min-Sec format LONGITUDE- Longitude in Deg-Min-Sec format POS_DATUM- Datum of the LATITUDE,LONGITUDE Should always be NAD83 DATUM_TAG- Datum Tag of the LATITUDE,LONGITUDE NAD83 (1986) indicates positions on the NAD83 datum for the North American Adjustment, completed in 1986. NAD83 (nnnn) indicates positions on the NAD83 datum for the North American Adjustment, but readjusted to a State High Accuracy Reference Network (HARN) on the date shown in (nnnn). NAD83 (CORS) indicates positions which are part of the CORS network. POS_SRCE- Position Source for the LATITUDE,LONGITUDE ADJUSTED = Least squares adjustment. (Lat,Lon Rounded to 5 decimal places.) HD_HELD1 = Differentially corrected hand held GPS observations. (Lat,Lon Rounded to 2 decimal places.) HD_HELD2 = Autonomous hand held GPS observations. (Lat,Lon Rounded to 1 decimal places.) SCALED = Scaled from a topographic map. (Lat,Lon Rounded to 0 decimal places.) ELEVATION- Present if available. The Orthometric Height in METERS indicating the height above the Geoid.
ELEV_DATUM- Datum of the ELEVATION ELEV_SRCE- Elevation Source for the ELEVATION ADJUSTED = Direct Digital Output from Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) ADJ UNCH = Manually Entered (and NOT verified) Output of Least Squares Adjustment of Precise Leveling. (Rounded to 3 decimal places.) POSTED = Pre-1991 Precise Leveling Adjusted to the NAVD 88 Network After Completion of the NAVD 88 General Adjustment of 1991. (Rounded to 3 decimal places.) READJUST = Precise Leveling Readjusted as Required by Crustal Motion or Other Cause. (Rounded to 2 decimal places.) N HEIGHT = Computed from Precise Leveling Connected at Only One Published Bench Mark. (Rounded to 2 decimal places.) RESET = Reset Computation of Precise Leveling. (Rounded to 2 decimal places.) COMPUTED = Computed from Precise Leveling Using Non-rigorous Adjustment Technique. (Rounded to 2 decimal places.) LEVELING = Precise Leveling Performed by Horizontal Field Party. (Rounded to 2 decimal places.) H LEVEL = Level between control points not connected to bench mark. (Rounded to 1 decimal places.) GPS OBS
= Computed from GPS Observations. (Rounded to 1 decimal places.) VERT ANG = Computed from Vertical Angle Observations. (Rounded to 1 decimal place; If No Check, to 0 decimal places.) SCALED = Scaled from a Topographic Map. (Rounded to 0 decimal places.) U HEIGHT = Unvalidated height from precise leveling connected at only one NSRS point. (Rounded to 2 decimal places.) VERTCON = The NAVD 88 height was computed by applying the VERTCON shift value to the NGVD 29 height. (Rounded to 0 decimal places.) ELLIP_HT- Present if available. The ellipsoid height in METERS referenced to GRS80 ellipsoid. ELLIP_SRCE- Ellipsoid Ht Source for the ELLIP_HT Should always be GPS_OBS when present. POS_ORDER- Order of accuracy for the LATITUDE,LONGITUDE Should be one of the following- A,B,1,2,3 Order and class for Orders 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication "Standards and Specifications for Geodetic Control Networks". In addition- Order A stations have a relative accuracy of 5 mm +/- 1-10,000,000 relative to other A-order stations. Order B stations have a relative accuracy of 8 mm +/- 1- 1,000,000 relative to other A- and B-order stations. POS_CHECK- Y=Observational Check was made for the position, N=NO Observational Check was made for the positions ELEV_ORDER- Order of accuracy for the ELEVATION Should be 1,2, or 3 for Vertical Control Stations. Will be blank for stations used for Horizontal Control only. Also see attribute DIST_RATE which is used for some vertical control stations. Elevation order and class for 1, 2, and 3 are defined in the Federal Geodetic Control Committee publication
"Standards and Specifications for Geodetic Control Networks". In addition- Vertical control which were determined only for the purpose of supplying a height for Horizontal Distance Reductions are assigned an order of 3. Class 0 is used for special
cases of orthometric vertical control as follows- Vertical Order/Class Tolerance Factor --
------------------ ---------------- 1 class 0 2.0 mm or less 2 class 0 8.4 mm or less 3
class 0 12.0 mm or less ELEV_CLASS- Should be 0, 1, or 2 See details under ELEV_ORDER ELEV_CHECK- Y=Observational Check was made for the orthometric height, N=NO Observational Check was made for the orthometric heights VERTCONED- Y=Orthometric Height was determined by applying VERTCON to an old NGVD 29 height. N=Orthometric Height determined by observations. DIST_RATE- Distribution rate for POSTED and READJUSTED benchmarks which do not have an Order and Class are as follows "Posted bench marks" are vertical control points in the NGS data base which were excluded from the NAVD 88 general adjustment. Some of the bench marks were excluded due to large adjustment residuals, possibly caused by vertical movement of the bench marks during the time interval between different leveling epochs. Adjusted NAVD 88 are computed for posted bench marks by supplemental adjustments. A range of mean distribution rate corrections is listed for each posted bench mark in the data portion of the publication. A summary table of the mean distribution rates and their codes is listed below. The mean distribution rate corrections which were applied to the original leveling observations is a good indication of the usefulness of the posted bench marks' adjusted NAVD 88 heights. Distribution Distribution Rate Code Rate Correction "a" 0.0 thru 1.0
mm/km "b" 1.1 thru 2.0 " "c" 2.1 thru 3.0 " "d" 3.1 thru 4.0 " "e" 4.1 thru 8.0 " "f" greater than 8.0 mm/km POSTED BENCH MARKS SHOULD BE USED WITH CAUTION.
As is the case for all leveling projects, the mandatory FGCS check leveling two-mark or three-mark tie procedure will usually detect any isolated movement (or other problem) at an individual bench mark. Of course, regional movement affecting all the marks equally is not detected by the two- or three-mark tie procedure. ELLP_ORDER- Order of accuracy for the ELLIP_HT Should be 1,2,3,4, or 5 if present. The following ellipsoid height order and class relative accuracy standards have not yet been adopted by the Federal Geodetic Control Subcommittee, but are currently in use by NGS- Ellipsoid Height Maximum Height Classification Difference Accuracy ------------------ -------------
------ 1 class 1 0.5 (mm)/sqrt(km) 1 class 2 0.7 2 class 1 1.0 2 class 2 1.3 3 class 1
2.0 3 class 2 3.0 4 class 1 6.0 4 class 2 15.0 5 class 1 30.0 5 class 2 60.0 The ellipsoid height difference accuracy (b) is computed from a a minimally constrained correctly weighted least squares adjustment by- b = s / sqrt(d) where b = height difference accuracy s = propagated standard deviation of ellipsoid height difference in millimeters between control points obtained from the least squares adjustment. d = horizontal distance between control points in kilometers ELLP_class- Class of accuracy for ELLIP_HT Should be 1 or 2 See details under ELLP_ORDER FIRST_RECV- Date when the station was first monumented or in the case of landmarks, first observed. LAST_RECV- Date when the station was last recovered. LAST_COND- Last recovered condition of the mark. Should be one of the following- MONUMENTED FIRST OBSERVED GOOD POOR MARK NOT FOUND SEE DESCRIPTION DESTROYED LAST_RECBY- Agency who reported the last condition of the mark. STABILITY- The stability of the mark may have 1 of 4 codes as indicated below- A = MOST RELIABLE AND EXPECTED TO HOLD POSITION/ELEVATION WELL B = PROBABLY HOLD POSITION/ELEVATION WELL C = MAY HOLD, BUT OF TYPE COMMONLY SUBJECT TO SURFACE MOTION - E.G. FROST HEAVE, ETC D = MARK OF QUESTIONABLE OR UNKNOWN STABILITY
ENTITY AND ATTRIBUTE DETAIL CITATION
All values were obtained from the NGA Datasheet available at
<http://www.ngs.noaa.gov/cgi-bin/datasheet.prl>
Hide Entities and Attributes ▲