Details for Benchmark: KX1489
N 40° 27.483 W 079° 54.383 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In ALLEGHENY county, PA View Original Datasheet
- Marker Type:
- survey disk
- massive structures
- Probably hold position/elevation well.
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Documented History (by the NGS)
|Unknown by PA6600 (MONUMENTED)
|01/01/1941 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1941
5.9 MI N FROM BRADDOCK. ABOUT 5.9 MILES NORTH ALONG THE PENNSYLVANIA RAILROAD FROM BRADDOCK, ALLEGHENY COUNTY, AT THE FRANKSTOWN AVENUE UNDERPASS, IN THE TOP OF THE BOTTOM TIER OF STONES, 30 FEET SOUTH OF THE CENTER LINE OF FRANKSTOWN AVENUE, 43 FEET WEST OF THE CENTER LINE OF LA SCHALL STREET, AND ABOUT 18 FEET LOWER THAN THE RAIL. A DEPARTMENT OF PUBLIC WORKS BRONZE DISK, STAMPED B.M. 101.
- 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.