Details for Benchmark: RD1266
N 45° 45.017 W 123° 39.217 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In TILLAMOOK county, OR View Original Datasheet
- A 97
- Marker Type:
- bench mark disk
- massive structures
- Probably hold position/elevation well.
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Documented History (by the NGS)
|1/1/1934 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1934
IN SALMONBERRY. ALONG THE SOUTHERN PACIFIC R.R., 15 RAIL LENGTHS WEST OF STATION, 32 RAIL LENGTHS EAST OF MILE POST 816, SET IN THE WEST ABUTMENT OF BRIDGE NO. 1-815E OVER THE NEHALEM RIVER, 5.5 FEET SOUTH OF TRACK.
- 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.