Details for Benchmark: BM0437
N 30° 04.050 W 097° 18.917 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In BASTROP county, TX View Original Datasheet
- Q 806
- Marker Type:
- bench mark 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)
|01/01/1953 by CGS (MONUMENTED)
|01/01/1973 by NGS (GOOD)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1973
3.1 MI SE FROM BASTROP. ABOUT 3.1 MILES SOUTHEAST ALONG THE MISSOURI, KANSAS AND TEXAS RAILROAD FROM THE STATION AT BASTROP, 18.5 FEET EAST OF THE 3RD TELEPHONE POLE AND SOUTHEAST OF MIPOST 957, 37.0 FEET WEST OF THE CENTER LINE OF A CURVE IN A GRADED DIRT ROAD, 49.5 FEET NORTHEAST OF THE NORTHEAST RAIL, 8.5 FEET SOUTHEAST OF A CORNER POST, 1.1 MILES SOUTHEAST OF BM P 806, 1.0 FEET NORTHEAST OF A METAL WITNESS POST AND ABOUT 2 1/2 FEET BELOW THE LEVEL OF THE TRACK, THE DISK IN THE TOP OF A CONCRETE POST WAS PROJECTING 6-IN.
|01/01/1978 by NGS (GOOD)
|RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1978
RECOVERED IN GOOD CONDITION.
- 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. WARNING-Repeat measurements at this control monument indicate possible vertical movement.
- 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.