Details for Benchmark: MJ0413
N 41° 26.817 W 095° 06.700 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In CASS county, IA View Original Datasheet
- Marker Type:
- pipe cap
- set into the top of a metal pipe driven into the ground
- Mark of questionable or unknown stability.
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Documented History (by the NGS)
|Unknown by USGS (MONUMENTED)
|01/01/1949 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1949
AT MARNE. AT MARNE, ABOUT 200.0 FEET SOUTHWEST OF THE CHICAGO, ROCK ISLAND AND PACIFIC RAILWAY STATION, 102.2 FEET NORTHWEST OF THE NORTHWEST CORNER OF A CONCRETE BRIDGE, 102.7 FEET SOUTH OF THE SOUTH RAIL OF THE MAIN TRACK, 90.0 FEET EAST OF THE NORTHEAST CORNER OF THE HOUSE OCCUPIED BY DOUGLAS POLKINGHARM, 39.0 FEET SOUTH OF THE CENTER LINE OF A DIRT ROAD, 59.0 FEET WEST OF THE CENTER LINE OF A DIRT ROAD LEADING SOUTH TO STATE HIGHWAY NO. 83, 22.0 FEET NORTHWEST OF THE NORTHEAST CORNER OF THE CONCRETE FOUNDATION OF THE PUMPING STATION, 28.8 FEET NORTH OF THE NORTHWEST CORNER OF THE BRICK FOUNDATION OF THE PUMPING STATION, 70.2 FEET SOUTH OF THE SOUTHEAST CORNER OF A CONCRETE RAILROAD CULVERT, 7.5 FEET NORTHWEST OF A YOUNG ASH TREE, 0.6 FOOT EAST OF A REFERENCE POST, A BRONZE CAP RIVETED ON TOP OF A 3 1/2-INCH IRON PIPE AND 0.3 FOOT BELOW GROUND LEVEL.
|01/01/1950 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1950
RECOVERED IN GOOD CONDITION.
- 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.