Details for Benchmark: HY1179
N 38° 44.117 W 082° 59.633 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In SCIOTO county, OH View Original Datasheet
- 354 B
- Marker Type:
- survey disk
- massive structures
- Probably hold position/elevation well.
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Documented History (by the NGS)
|Unknown by DOD (MONUMENTED)
|01/01/1967 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1967
AT PORTSMOUTH. AT PORTSMOUTH, AT THE POST OFFICE BUILDING, NEAR THE INTERSECTION OF GAY AND 6TH STREET, SET ON THE TOP OF THE SOUTHEAST CORNER OF THE PEDESTAL AT THE WEST ENTRANCE TO BUILDING, 103 FEET NORTH OF THE NORTH CURB OF 6TH STREET, 24 FEET EAST OF THE EAST CURB OF GAY STREET, 11 FEET SOUTH OF THE SOUTH EDGE OF THE SOUTH DOOR AT WEST ENTRANCE AND 3 1/2 FEET ABOVE THE LEVEL OF THE SIDEWALK.
- 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.