Details for Benchmark: ND0012
N 42° 06.950 W 080° 05.850 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In ERIE county, PA View Original Datasheet
- G 13
- Marker Type:
- bench mark disk
- light structures
- Mark of questionable or unknown stability.
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Documented History (by the NGS)
|01/01/1934 by CGS (MONUMENTED)
|01/01/1961 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1961
0.9 MI W FROM ERIE. 0.9 MILE WEST ALONG THE NEW YORK CENTRAL RAILROAD FROM THE STATION AT ERIE, ERIE COUNTY, AT BRIDGE NO. 257 OVER LIBERTY STREET, AT THE SOUTH END OF THE WEST ABUTMENT, IN THE TOP OF THE TOP STEP, 22 FEET SOUTH OF THE SOUTH RAIL OF THE SOUTH TRACK, AND LEVEL WITH THE TOP OF THE RAIL. A STANDARD DISK, STAMPED G 13 1934.
|01/01/1971 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1971
RECOVERED IN GOOD CONDITION.
|01/01/1981 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1981
RECOVERED IN GOOD CONDITION. NEW DESCRIPTION FOLLOWS. IN ERIE, AT THE CONRAIL (AMTRACK) RAILROAD BRIDGE OVER LIBERTY STREET, 1.4 KILOMETER (0.9 MILE) WEST OF THE AMTRACK PASSENGER STATION, THE MARK IS IN THE TOP OF THE SOUTHEAST END OF THE NORTHEAST ABUTMENT OF THE BRIDGE, 14.63 METERS (48.0 FEET) SOUTHEAST OF THE SOUTHEAST RAIL AND 0.60 METER (2.0 FEET) SOUTHEAST OF THE NORTHEAST END OF THE SOUTHEAST METAL PIPE GUARDRAIL OF THE BRIDGE. THE MARK IS ABOVE LEVEL WITH THE RAIL.
- 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.