Details for Benchmark: NE0869
N 42° 18.850 W 083° 04.517 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In WAYNE county, MI View Original Datasheet
- Marker Type:
- survey disk
- massive structures with deep foundations
- Most reliable and expected to hold position/elevation well.
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Documented History (by the NGS)
|01/01/1959 by USE (MONUMENTED)
|01/01/1980 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1980
IN DETROIT. IN DETROIT, UNDER THE AMBASSADOR BRIDGE SET IN THE TOP AND ON SOUTH- EAST SIDE OF THE NORTHEAST CONCRETE FOUNDATION OF THE NORTHEAST ONE OF TWO STEEL PIERS, WHICH IS NEAREST TO THE RIVER. NOTE-THIS IS A MASSIVE STRUCTURE.
|01/01/1985 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1985
RECOVERED IN GOOD CONDITION. ADD--248.7 M (815.9 FT) SOUTHEAST OF THE CENTER OF JEFFERSON AVENUE, AND 15.2 M (49.9 FT) SOUTHWEST OF THE EXTENDED CENTER OF 21ST STREET.
|09/25/1999 by USPSQD (MARK NOT FOUND)
|RECOVERY NOTE BY US POWER SQUADRON 1999
MARK NOT FOUND.
- 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. WARNING-Repeat measurements at this control monument indicate possible vertical movement.
- 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.