Details for Benchmark: AB9143
N 44° 32.833 W 101° 55.767 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In ZIEBACH county, SD View Original Datasheet
- 34 122.59
- Marker Type:
- survey disk
- set into the top of a round concrete monument
- May hold, but of type commonly subject to surface motion.
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Documented History (by the NGS)
|Unknown by SDDT (MONUMENTED)
|06/05/1995 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1995 (GAS)
15.2 KM (9.45 MI) EASTERLY ALONG STATE HIGHWAY 34 FROM THE JUNCTION OF STATE HIGHWAY 73 IN HOWES, 693.0 M (2273.6 FT) WEST OF MILEPOST 123, 30.1 M (98.8 FT) EAST OF THE HIGHWAY CENTERLINE, 0.9 M (3.0 FT) WEST OF A FENCE, 0.5 M (1.6 FT) BELOW THE LEVEL OF THE HIGHWAY, 0.4 M (1.3 FT) WEST OF A WITNESS POST, AND THE MONUMENT PROJECTS 0.1 M (0.3 FT) ABOVE THE GROUND SURFACE.
- 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 October 1997.
- 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.