Details for Benchmark: AF8756
N 42° 50.167 W 124° 33.220 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is ADJUSTED. (more info)
- In CURRY county, OR View Original Datasheet
- CAB1 B
- Marker Type:
- metal rod
- stainless steel rod
- Probably hold position/elevation well.
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Documented History (by the NGS)
|1/1/1998 by NGS (MONUMENTED)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1998 (GAS)
0.1 KM (0.05 MI) WESTERLY ALONG 7TH STREET FROM THE POST OFFICE IN PORT ORFORD, THENCE 7.2 KM (4.45 MI) NORTHERLY ALONG U.S. HIGHWAY 101, THENCE 8.0 KM (4.95 MI) WESTERLY ALONG A PAVED ROAD LEADING TO THE CAPE BLANCO LIGHTHOUSE, 22.8 M (74.8 FT) NORTHEAST OF THE NORTH LEG OF A SIGN (CAPE BLANCO STATE PARK CAMPGROUND) , 21.0 M (68.9 FT) EAST OF THE EXTENDED CENTER OF A PAVED ROAD LEADING TO THE CAMPGROUND, 18.7 M (61.4 FT) NORTH OF THE ROAD CENTERLINE, 12.4 M (40.7 FT) SOUTH OF UTILITY POLE NUMBER 20-70 WITH A GUY CABLE, 4.5 M (14.8 FT) SOUTH OF A WITNESS POST, AND 0.3 M (1.0 FT) BELOW THE LEVEL OF THE ROAD. NOTE--ACCESS TO THE DATUM POINT IS THROUGH A 5-INCH LOGO CAP. THE SLEEVE DEPTH DOES NOT MEET THE SPECIFICATIONS FOR A CLASS A MARK.
|12/11/1998 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1998 (CLS)
RECOVERED AS DESCRIBED.
- The horizontal coordinates were established by GPS observations and adjusted by the National Geodetic Survey in April 2000. This is a SPECIAL STATUS position. See SPECIAL STATUS under the DATUM ITEM on the data sheet items page. The horizontal coordinates are valid at the epoch date displayed above. The epoch date for horizontal control is a decimal equivalence of Year/Month/Day.
- The orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in May 2000.
- The X, Y, and Z were computed from the position and the ellipsoidal ht.
- The Laplace correction was computed from DEFLEC99 derived deflections.
- The ellipsoidal height was determined by GPS observations and is referenced to NAD 83.
- 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.