Details for Benchmark: NC0660
N 42° 10.983 W 079° 50.083 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In ERIE county, PA View Original Datasheet
- PUTNAM RM 1
- Marker Type:
- reference mark disk
- set into the top of a round concrete monument
- May hold, but of type commonly subject to surface motion.
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Documented History (by the NGS)
|01/01/1961 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1961
2.67 MI SW FROM NORTHEAST. ABOUT 2.27 MILES SOUTH ALONG STATE HIGHWAY 89 FROM PUBLIC SCHOOL NO 1 IN NORTHEAST TO THE INTERCHANGE BRIDGE OVER INTERSTATE HIGHWAY 90, THENCE WEST ALONG INTERSTATE HIGHWAY 90 FOR 0.4 MILES, 105.0 FEET NORTHWEST OF CENTER OF A GRAVELED ROAD, 76.7 FEET NORTHEAST OF THE STATION MARK, 74.9 FEET NORTHEAST OF A STANDARD METAL WITNESS POST. IT IS SET IN TOP OF A CONCRETE MONUMENT ABOUT FLUSH WITH THE SURFACE OF THE GROUND AND ABOUT 100 FEET ABOVE THE LEVEL OF THE HIGHWAY.
- 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.