Details for Benchmark: JT2172
N 38° 01.976 W 122° 07.736 (NAD 83)
Coordinates may not be exact. Altitude is UNKNOWN and location is ADJUSTED. (more info)
- In CONTRA COSTA county, CA View Original Datasheet
- MARTINEZ SHELL CO PIER NE LT
- Marker Type:
- NGS Benchmark
- setting not listed - see description
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Documented History (by the NGS)
|01/01/1949 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1949 (CAG)
THE LIGHT STAND ON THE NORTHEASTERLY CORNER OF THE SHELL OIL CO. PIER AT MARTINEZ. THE STAND IS 15 FEET HIGH, 4.5 FEET SQUARE AT THE BASE, AND 20 FEET FROM THE END OF THE CAT-WALK. THE LIGHT IS A REVOLVING, WHITE LIGHT AND APPARENTLY IT IS MAINTAINED BY THE SHELL OIL CO. IT IS NOT LISTED IN THE LIGHT LIST.
THIS IS AN INTERSECTION STATION.
|01/01/1962 by CGS (MONUMENTED)
|RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1962 (IRR)
THE END OF THE PIER ON WHICH THE LIGHT WAS LOCATED HAD TO BE REBUILT IN 1955 AFTER BEING STRUCK BY A SHIP. STATION LOST.
- The horizontal coordinates were established by classical geodetic methods and adjusted by the National Geodetic Survey in March 1994. The horizontal coordinates are valid at the epoch date displayed above. The epoch date for horizontal control is a decimal equivalence of Year/Month/Day.
- The Laplace correction was computed from DEFLEC99 derived deflections.
- The geoid height was determined by GEOID99.