Details for Benchmark: TT0870
N 61° 13.883 W 149° 45.450 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In county, AK View Original Datasheet
- O 1 USE
- Marker Type:
- survey 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)
|01/01/1951 by DOD (MONUMENTED)
|01/01/1975 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1975
1.05 MI NW FROM ANCHORAGE. 1.05 MILES WEST ALONG OILWELL ROAD FROM THE JUNCTION OF STATE HIGHWAY 1 AND MULDOON ROAD AT ANCHORAGE, 0.1 MILE WEST OF THE JUNCTION OF A ROAD LEADING NORTH TO THE ELMENDORF AIR FORCE HOSPITAL AND HOSPITAL DRIVE LEADING SOUTH, 49 1/2 FEET SOUTH OF THE CENTER LINE OF THE ROAD, 64 1/2 FEET WEST OF POWER LINE POLE 54-73, 81 1/2 FEET EAST OF POWER LINE POLE 54-72, ABOUT 1 FOOT HIGHER THAN THE ROAD, AND SET IN THE TOP OF A CONCRETE POST PROJECTING 0.1 FOOT ABOVE THE GROUND. SECTION 11 ,T 13N ,R 3W.
- 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.