Details for Benchmark: DA0517
N 32° 45.117 W 112° 49.467 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In MARICOPA county, AZ View Original Datasheet
- R 5
- Marker Type:
- survey disk
- in a boulder
- May hold, but of type commonly subject to surface motion.
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Documented History (by the NGS)
|01/01/1930 by USGS (MONUMENTED)
|01/01/1953 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1953
15.0 MI S FROM GILA BEND. 15.0 MILES SOUTH ALONG STATE HIGHWAY 85 FROM THE SOUTHERN PACIFIC COMPANY RAILROAD STATION AT GILA BEND, 5 POLES SOUTH OF TUCSON, CORNELIA AND GILA BEND RAILROAD MILEPOLE 15, AT BLACK GAP, AT THE BASE OF A ROCK-COVERED HILL, IN THE TOP OF A 9- BY 13-FOOT BOULDER, 101.4 FEET EAST OF THE EAST RAIL OF THE RAILROAD TRACK, 2.9 FEET NORTHEAST OF A WITNESS POST, ABOUT 5 1/2 FEET HIGHER THAN THE TRACK, AND ABOUT 5 FEET ABOVE THE GROUND.
|01/01/1980 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1980
23.8 KM (14.8 MI) SOUTHWEST ALONG THE TUCSON, CORNELIA AND GILA BEND RAILWAY FROM THE MARTIN AVENUE CROSSING IN GILA BEND, 0.2 KM (0.1 MI) NORTHEAST OF THE NORTHEAST END OF A METAL GATE IN THE SOUTHEAST RIGHT-OF-WAY FENCE, 5 TELEGRAPH POLES SOUTH OF RAILWAY MILEPOLE 15, A STATE HIGHWAY 85 MILEPOST 15, AT BLACK GAP, SET IN TOP OF A LAVA ROCK OUTCROP AT THE NORTHWEST END OF A HILL, 30.9 METERS (101.4 FT) SOUTHEAST OF THE SOUTHEAST RAIL OF THE TRACKS. THE MARK IS 0.3 METERS NE FROM A WITNESS POST. THE MARK IS 1.5 M ABOVE THE TRACKS.
- 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.