Details for Benchmark: MC0260
N 41° 30.800 W 082° 56.300 (NAD 83)
Altitude: 576.99
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- Location:
- In OTTAWA county, OH View Original Datasheet
- Designation:
- PORT CLINTON
- Marker Type:
- bench mark disk
- Setting:
- light structures
- Stability:
- Mark of questionable or unknown stability.
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Documented History (by the NGS)
01/01/1934 by CGS (MONUMENTED) |
DESCRIBED BY COAST AND GEODETIC SURVEY 1934
AT PORT CLINTON. AT PORT CLINTON, OTTAWA COUNTY, AT THE CITY WATER WORKS, IN THE WEST END OF THE TOP STEP AT THE SOUTH ENTRANCE, 24.4 FEET NORTHWEST OF THE EDGE OF THE ROUND BRICK FISH POND, 2 FEET SOUTH OF THE SOUTH FACE OF THE BUILDING, AND ABOUT 2 FEET ABOVE THE GROUND. A STANDARD DISK, STAMPED PORT CLINTON 1934. |
01/01/1980 by NGS (GOOD) |
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1980
RECOVERED IN GOOD CONDITION. |
01/01/1984 by NGS (GOOD) |
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1984
RECOVERED IN GOOD CONDITION. |
Control Text
- 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.