Details for Benchmark: JT2169
N 38° 01.834 W 122° 07.785 (NAD 83)
Coordinates may not be exact. Altitude is UNKNOWN and location is ADJUSTED. (more info)
- In CONTRA COSTA county, CA View Original Datasheet
- Marker Type:
- NGS Benchmark
- setting not listed - see description
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Documented History (by the NGS)
|01/01/1914 by CGS (MONUMENTED)
|DESCRIBED BY COAST AND GEODETIC SURVEY 1914 (FM)
STATION IS IRON STACK ON PUMPING PLANT ON OIL COMPANYS LONG WHARF AT MARTINEZ. THE DOCK IS THE FIRST ONE E FROM THE NEW FERRY DOCK.
|01/01/1939 by CGS (MONUMENTED)
|RECOVERY NOTE BY COAST AND GEODETIC SURVEY 1939 (RDH)
STATION WAS DESTROYED DURING IMPROVEMENTS TO THE DOCK.
- 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.