Details for Benchmark: JT9530
N 38° 07.800 W 122° 13.533 (NAD 83)
Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)
- In SOLANO county, CA View Original Datasheet
- H 1394
- Marker Type:
- metal rod
- stainless steel rod
- Most reliable and expected to hold position/elevation well.
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Documented History (by the NGS)
|01/01/1987 by NGS (MONUMENTED)
|DESCRIBED BY NATIONAL GEODETIC SURVEY 1987
1.3 KM (0.80 MI) SW FROM VALLEJO. 1.3 KM (0.80 MI) SOUTHWESTERLY ALONG INTERSTATE HIGHWAY 80 FROM THE JUNCTION OF STATE HIGHWAY 37 IN VALLEJO, 21.7 M (71.2 FT) SOUTHWEST OF A FENCE CORNER, AND 16.5 M (54.1 FT) NORTHWEST OF THE CENTER OF THE MOST WESTERLY WESTBOUND LANES OF THE HIGHWAY. NOTE--ACCESS TO THE DATUM POINT IS THROUGH A 5-INCH LOGO CAP. THE MARK IS 0.3 METERS SE FROM A WITNESS POST AND FENCE THE MARK IS ABOVE LEVEL WITH THE HIGHWAY.
- 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.