Details for Benchmark: GP0257
N 36° 42.950 W 111° 46.467 (NAD 83)
Coordinates may not be exact. Altitude is POSTED and location is SCALED. (more info)
- In COCONINO county, AZ View Original Datasheet
- Marker Type:
- survey disk
- light structures
- Mark of questionable or unknown stability.
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Documented History (by the NGS)
|01/01/1934 by AZHD (MONUMENTED)
|DESCRIBED BY ARIZONA HIGHWAY DEPARTMENT (NOW AZDT) 1934
10.9 MI SW FROM MARBLE CANYON. 10.9 MILES SOUTHWEST ALONG U.S. HIGHWAY 89 FROM THE POST OFFICE AT MARBLE CANYON, COCONINO COUNTY, AT AN 8- BY 10-FOOT CONCRETE-BOX CULVERT, AND IN THE CENTER OF THE TOP OF THE NORTH HEADWALL. AN ARIZONA STATE HIGHWAY DEPARTMENT STANDARD DISK, STAMPED 4312.04 602+73.0 1934.
- 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 1992. * This is a POSTED BENCH MARK height. Code A indicates a distribution rate of 0.0 thru 1.0 mm/km.
- 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.