Details for Benchmark: RK0131
N 46° 34.783 W 087° 25.600 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In MARQUETTE county, MI View Original Datasheet
- E 165
- Marker Type:
- bench mark disk
- in rock outcrop
- Most reliable and expected to hold position/elevation well.
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Documented History (by the NGS)
|01/01/1948 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1948
2.8 MI NW FROM MARQUETTE. 0.55 MILE NORTH ALONG PRESQUE ISLE AVENUE FROM THE NORTHERN MICHIGAN STATE COLLEGE AT MARQUETTE, THENCE ABOUT 2.25 MILES NORTHWEST ALONG COUNTY ROAD 550, ABOUT 0.5 MILE NORTHWEST OF THE CROSSING OF THE LAKE SUPERIOR AND ISHPEMING RAILWAY, SET IN THE TOP OF THE NORTHWEST END OF A LARGE PROMINENT OUTCROPPING OF ROCK, 116 FEET NORTH AND ACROSS THE ROAD FROM A TRANSFORMERS POWER POLE, 83 FEET EAST AND ACROSS THE ROAD FROM THE SOUTHEAST CORNER OF A HOUSE, 33 FEET EAST-NORTHEAST OF THE CENTER LINE OF THE ROAD, 50 FEET SOUTHEAST OF A TRIANGULAR BLAZED 7-INCH PINE TREE, 2 FEET NORTHEAST OF THE SOUTHWEST EDGE OF THE ROCK AND ABOUT 5 FEET ABOVE THE ROAD.
- 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.