Details for Benchmark: MF0103
N 41° 35.350 W 088° 03.450 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In WILL county, IL View Original Datasheet
- SD 116
- Marker Type:
- massive structures
- Probably hold position/elevation well.
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Documented History (by the NGS)
|Unknown by DOD (MONUMENTED)
|01/01/1935 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1935
AT LOCKPORT. AT LOCKPORT, AT THE SOUTHWEST CORNER OF THE INTERSECTION OF STATE AND NINTH STREET, AT A TWO-STORY BRICK BUILDING OWNED IN 1934 BY THOMAS FARREL (FORMERLY KNOWN AS THE ARNOLD BUILDING), 21.7 FEET WEST OF THE NORTHEAST CORNER OF THE BUILDING, AND IN THE NORTH WATER TABLE. THE CENTER PUNCH MARK IN THE END OF A COPPER BOLT LEADED IN THE STONE, MARKED SD.
- The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
- The orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in June 1991.
- The geoid height was determined by GEOID99.
- The dynamic height is computed by dividing the NAVD 88 geopotential number by the normal gravity value computed on the Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45 degrees latitude (g = 980.6199 gals.).
- The modeled gravity was interpolated from observed gravity values.