Details for Benchmark: MB0156
N 41° 56.600 W 080° 29.933 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In ERIE county, PA View Original Datasheet
- N 273
- Marker Type:
- bench mark disk
- light structures
- Mark of questionable or unknown stability.
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Documented History (by the NGS)
|01/01/1961 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1961
2.2 MI SW FROM WEST SPRINGFIELD. ABOUT 1.8 MILES WEST ALONG INTERSTATE HIGHWAY 90 FROM THE JUNCTION OF U.S. HIGHWAY 6N AND INTERSTATE HIGHWAY 90. IT IS DRILLED IN A SMALL CULVERT ABOUT 3.0 FEET LOWER THAN THE HIGHWAY, APPROXIMATELY .05 MILE EAST OF AN OVERHEAD BRIDGE, AND 45.1 FEET NORTH OF THE CENTER OF THE WEST BOUND LANE OF TRAFFIC OF INTERSTATE HIGHWAY 90.
|01/01/1975 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1975
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.