2017-04-09

GT0292 "3926 1905"

This early 1900s U.S. Geologic Survey Benchmark is located a the Inyo County courthouse in the beautiful town of Independence, Ca. The mark is set in the westerly face the southerly balustrade of the front steps of the Courthouse.

The coordinates shown by the GPSr were dramatically different from the published coordinates to the tune of about 1250 feet horizontally. I imagine it was due to signal multi-path or signal shadow caused by the building. Interestingly, the elevation was only 143 feet. I would have expected more given the horizontal error.

Regardless of the coordinates or GPSr error, the goto description on the datasheet is clear and makes finding the mark easy.
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Found Details for Benchmark: GT0292
N 36°48.212', W 118°11.985' (NAD 83)
Altitude: 3786
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Published Details for Benchmark: GT0292
N 36°48.100', W 118°12.200' (NAD 83)
Altitude: 3929.89

Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED.

Location: In INYO county, CA
Designation: 3926
Marker Type: survey disk
Setting: massive structures
Stability: Most reliable and expected to hold position/elevation well.

Documented History (by the NGS)
01 Jan 05 by USGS (MONUMENTED)

01 Jan 62 by NGS (GOOD)
DESCRIBED BY NATIONAL GEODETIC SURVEY 1962 AT INDEPENDENCE. AT INDEPENDENCE, AT THE COUNTY COURTHOUSE, SET VERTICALLY IN THE WEST-SOUTHWEST FACE OF THE SOUTH-SOUTHEAST ONE OF TWO BALISTRADES AT THE WEST-SOUTHWEST (MAIN) ENTRANCE, 15 1/2 FEET SOUTH-SOUTHEAST OF THE CENTER OF THE STEPS LEADING INTO THE BUILDING, 2.0 FEET ABOVE THE FIRST LANDING ABOVE THE GROUND, AND ABOUT 3 1/2 FEET ABOVE THE GROUND.

01 Jan 87 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1987 RECOVERED IN GOOD CONDITION.

GT0292 "3926 1905" - Benchmark detail.
GT0292 "3926 1905" - Benchmark, GPSr, and coordinates shown.
GT0292 "3926 1905" - Benchmark setting in the southerly balustrade of the Inyo County Courthouse in Independence, Ca.
GT0292 "3926 1905" - The impressive entrance to the Inyo County Courthouse in Independence, Ca.
GT0292 "3926 1905" - The copper cladded doors at the entrance to the Inyo County Courthouse in Independence, Ca.
GT0292 "3926 1905" - Plaque on the Inyo County Courthouse in Independence, Ca.
GT0292 "3926 1905" -  The view from the steps of the Inyo County Courthouse in Independence, Ca.