Details for Benchmark: OB0241
N 43° 47.400 W 069° 56.917 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In CUMBERLAND county, ME View Original Datasheet
- N 97
- Marker Type:
- bench mark disk
- in rock outcrop
- Most reliable and expected to hold position/elevation well.
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Documented History (by the NGS)
|01/01/1943 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1943
2.6 MI NE FROM ORRS ISLAND. 2.6 MILES NORTHEAST ALONG STATE HIGHWAY 24 FROM THE POST OFFICE AT ORRS ISLAND, CUMBERLAND COUNTY, 0.4 MILE SOUTH OF ORRS ISLAND BRIDGE, NEAR THE TOP OF A HILL, 36 FEET WEST OF THE CENTER LINE OF THE HIGHWAY, 7 FEET WEST OF POLE 437, 3.6 FEET SOUTHEAST OF THE POLE GUY-WIRE ANCHOR, AND IN THE TOP OF AN OUTCROP OF BEDROCK. A STANDARD DISK, STAMPED N 97 1943.
|01/01/1978 by LOCENG (GOOD)
|RECOVERY NOTE BY LOCAL ENGINEER (INDIVIDUAL OR FIRM) 1978
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.
- 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.