FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION

TITLE: USGS 1:24,000 SURVEY CONTROL AND MARKERS

Geodataset Name:     USGSSM
Geodataset Type:     SHAPE
Geodataset Feature:  POINT

GENERAL DESCRIPTION:

This dataset consists of information about the points of established position and third-order or better elevations that are used as fixed references in positioning and correlating map features.

DATA SOURCE(S):                         United States Geological Survey (USGS)
SCALE OF ORIGINAL SOURCE MAPS:          1:24,000
DATE OF AUTOMATION OR SOURCE:           USGS in 1987, FGDL in 1998

GEODATASET EXTENT:

This dataset covers the following counties: Alachua, Baker, Brevard, Broward, Charlotte, Citrus, Collier, Columbia, Dade, Desoto, Escambia, Hardee, Levy, Manatee, Marion, Monroe, Nassau, Orange, Palm Beach, Putnam, Santa Rosa, Sarasota, Seminole, and Volusia.

FEATURE ATTRIBUTE TABLES
Datafile Name: USGSSM.DBF

ITEM NAME        WIDTH   TYPE       PRECISION
  
AREA              18     DECIMAL       5 
PERIMETER         18     DECIMAL       5 
USGSSM_            5     DECIMAL       - 
USGSSM_ID          5     DECIMAL       - 
MODN_ID            5     DECIMAL       - 
ENTITY_LBL         7     CHARACTER     - 
STATE              2     CHARACTER     -
COUNTY             3     CHARACTER     -
ELEVATION         12     DECIMAL       3 
QUAD_COVER         8     DECIMAL       - 
SURV_AREA         28     CHARACTER     -
MAP_DATE           4     DECIMAL       -
DESCRIPT          12     DECIMAL       3

FEATURE ATTRIBUTE TABLES CODES AND VALUES:

Codes for ENTITIY_LBL item:

     MAJOR   MINOR     
     CODE    CODE   DESCRIPTION
     
     150     ----   Survey Control and Markers
      
             0300   Horizontal control station, third 
                    order or better, permanent mark
             0301   Horizontal and vertical control 
                    station, third order or better
             0303   Horizontal control station, checked
             0310   Vertical control station, third order 
                    or better, tablet
             0311   Vertical control station, recoverable 
                    mark, third order or better, no 
                    tablet
             0330   Reference monument
             0332   Other control point
             
MODN_ID    = Module number ID, relate item used to join feature
             attribute tables and .asmf (elevation data) tables.             
ELEVATION  = Elevation in meters.
QUAD_COVER = Coverage name of original quad coverages before 
             they were APPENDed to create "survmk" coverage.
SURV_AREA  = Survey area of original quad coverages.  There are several
             points for each survey area.
MAP_DATE   = Date of USGS topographic maps from which point coverages 
             were derived.
DESCRIPT   = Elevation data in meters. 

USER NOTES:

An elevation of -9999.990 indicates that there is no elevation data for a particular point.

FGDL QUALITY ASSURANCE STATUS:

-Joined the feature attribute tables and the related elevation
tables (.asmf) of the original quad coverages.
-Projected to FGDL Albers.
-Set tolerances to FGDL standards.

REFERENCES:

"Data Users Guide 1"--This is a guide that accompanies the DIGITAL LINE GRAPHS produced from 1:24,000-scale maps
by the United States Geologicial Survey.

It is available on the internet at the following address:

ftp://mapping.usgs.gov/pub/ti/DLG/24kdlgguide/dugdlg24.txt

DATA LINEAGE SUMMARY:

The point coverage described in this document was derived from USGS topographic maps published as 7.5-minute quadrangles at 1:24,000 scale.

MAP PROJECTION PARAMETERS

Projection                           ALBERS
Units                                METERS
Datum                                HPGN
Spheroid                             GRS1980
1st standard parallel                24   0  0.000
2nd standard parallel                31  30  0.000
central meridian                    -84   0  0.000
latitude of projection's origin      24   0  0.000 
false easting (meters)               400000.00000
false northing (meters)              0.00000

DATA SOURCES CONTACT(S):

Name:                   U.S. Geological Survey, Branch of Technical Management
Abbr.name:              USGS
Address:                510 National Center
                        Reston, Virginia  22092
Name:                   Customer Services, U.S. Geological Survey
                        EROS Data Center
Abbr.name:              USGS
Address:                47914 252nd Street
                        Sioux Falls, SD 57198-0001 
Phone:                  800-252-4547, 605-594-6151 
Fax:                    605-594-6589
TDD:                    605-594-6933
Web site:               http://www.usgs.gov
Email:                  custserv@edcmail.cr.usgs.gov

FGDL CONTACT:

Name:                   FLORIDA GEOGRAPHIC DATA LIBRARY
Abbr. Name:             FGDL
Address:                Florida Geographic Data Library
                        431 Architecture Building
                        PO Box 115706
                        Gainesville, FL  32611-5706
Web site:               http://www.fgdl.org

Contact FGDL:

      Technical Support:	        http://www.fgdl.org/fgdlfeed.html
      FGDL Frequently Asked Questions:  http://www.fgdl.org/fgdlfaq.html
      FGDL Mailing Lists:		http://www.fgdl.org/fgdl-l.html
      For FGDL Software:                http://www.fgdl.org/software.html