CU6478 "SW 7 NO 3 1952"
My Wife and I were able to spend a few days in and around Lone Pine and Independence, exploring the Alabama Hills, the Movie Museum, and Manzanar. Found some geocaches and benchmarks while we were there too, including this one.
Located in the Town of Independence, Inyo County, California, this USC&GS mark lies at the south edge of town. This mark, better known as Reference Monument No. 3 for GT1754, is stamped "SW 7 NO 3 1952" and was found at 10:30, 08 April 2017 as described and in generally good condition. Go to description is adequate to find the mark.
This mark is one of three reference monuments for GT1754 "SW 7". Interestingly, each one of the three reference marks is that each has a PID listed in the datasheet for this mark. Each of the datasheets for those marks included minimal information, stating "See SW 7".
This mark is unique in that it is nearly 550 feet away from the parent Triangulation Station. That's the farthest distance I've ever seen for a reference mark.
Triangulation Station "SW 7" = GT1754 - Found as Described
Reference Monument #1 = DA9332 - Found as described
Reference Monument #2 = DA9333 - Found remnants of destroyed concrete setting
Reference Monument #3 = CU6478 - Found as described
Found WGS84 coordinates for RM#3 are located about 537 feet northeasterly of the found WGS84 coordinates for GT1754. WGS84 coordinates for the mark found by 3 minute occupation with 9 strong satellites and 1 WAAS satellite.
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Found Details for Benchmark: CU6478
N 36° 47.895 W 118° 11.832 (WGS 84)
Altitude: 3935
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Published Details for Benchmark: CU6478
N 36° 47.824 W 118° 11.901 (NAD 83)
Altitude: 3955.72
Coordinates may not be exact. Altitude is ADJUSTED and location is ADJUSTED.
Location: In Inyo County, CA
Designation: SW 7
Marker Type: triangulation station disk
Setting: set into the top of a round concrete monument
Stability: May hold, but of type commonly subject to surface motion.
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| CU6478 "SW 7 NO 3 1952" - Reference Monument No. 3 (for GT1754). |
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| CU6478 "SW 7 NO 3 1952" - Reference Monument No. 3 (for GT1754) and GPSr coordinates. |
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| CU6478 "SW 7 NO 3 1952" - Reference Monument No. 3 (for GT1754) and GPSr. |
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| CU6478 "SW 7 NO 3 1952" - Reference Monument No. 3 (for GT1754) setting under the Mt. Williamson Motel sign. |
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| CU6478 "SW 7 NO 3 1952" - Reference Monument No. 3 (for GT1754) setting looking toward the benchmark GT1754. |
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| GT1754 "SW 7 NO 1 1952" - Benchmark "can" setting looking toward Reference Monument No. 3 (CU6478) which lies underneath the Mt. Williamson Motel sign. View northeasterly. |
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Documented History (by the NGS)
01 Jan 52 by CGS (MONUMENTED)
DESCRIBED BY COAST AND GEODETIC SURVEY 1952 (WRH) THE STATION IS LOCATED NEAR A TELEPHONE LINE AT THE SOUTH EDGE OF INDEPENDENCE, ABOUT 0.1 MILE WEST OF U.S. HIGHWAY 395, AND IN THE OPEN DESERT JUST SOUTH OF THE RESIDENTIAL AREA. TO REACH THE STATION FROM THE POST OFFICE IN INDEPENDENCE GO SOUTH ON U.S. HIGHWAY 395 FOR 0.4 MILE TO A CROSS ROAD. TURN RIGHT ONTO CITRUS STREET AND GO 0.1 MILE TO TELEPHONE POLE 5003 AND THE STATION ON THE LEFT. THE STATION MARK IS A 2-INCH BRONZE DISK STAMPED, SW 7 SET IN THE TOP OF CONCRETE POST ENCASED IN A 6-INCH IRON PIPE THAT PROJECTS 6 INCHES ABOVE THE GROUND. IT IS 54 FEET SOUTH-SOUTHWEST OF THE CENTERLINE OF A ROAD AND 36 FEET SOUTH-SOUTHWEST OF TELEPHONE POLE 5003. REFERENCE MARK NUMBER 1 IS A STANDARD DISK STAMPED, SW 7 NO 1 1952 SET IN THE TOP OF A 12-INCH CONCRETE CYLINDER THAT PROJECTS 4 INCHES ABOVE THE GROUND AND IS 8 INCHES LOWER THAN THE STATION. REFERENCE MARK NUMBER 2 IS A STANDARD DISK STAMPED, SW 7 NO 2 1952 SET IN THE TOP OF A 12-INCH CONCRETE CYLINDER THAT PROJECTS 4 INCHES ABOVE THE GROUND. IT IS 18 FEET WEST OF TELEPHONE POLE 5003 AND 8 INCHES LOWER THAN THE STATION. THE AZIMUTH MARK IS LOCATED ON THE WEST SIDE OF U.S. HIGHWAY 395 AND IS A STANDARD DISK STAMPED, SW 7 1952 SET IN THE TOP OF A 12-INCH CONCRETE CYLINDER THAT PROJECTS 3 INCHES ABOVE THE GROUND. IT IS 53 FEET WEST OF THE CENTERLINE OF THE HIGHWAY AND 3 FEET WEST-NORTHWEST OF A 6-INCH SQUARE CONCRETE HIGHWAY RIGHT-OF-WAY POST. TO REACH THE AZIMUTH MARK FROM THE POST OFFICE IN INDEPENDENCE GO SOUTH ON U.S. HIGHWAY 395 FOR 0.9 MILE TO A SIDE ROAD ON THE LEFT. KEEP STRAIGHT AHEAD ON THE HIGHWAY AND GO 0.1 MILE TO THE AZIMUTH MARK ON THE RIGHT.
01 Jan 87 by NGS (GOOD)
RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 1987 1.0 KM (0.60 MI) SOUTH FROM INDEPENDENCE. 0.8 KM (0.50 MI) SOUTH ALONG US HIGHWAY 395 FROM THE INYO COUNTY COURTHOUSE IN INDEPENDENCE, THENCE 0.16 KM (0.10 MI) WEST ALONG CITRUS STREET, 11.0 M (36.1 FT) SOUTHWEST OF TELEPHONE POLE 5003, 16.5 M (54.1 FT) SOUTHWEST OF THE CENTER OF THE DIRT ROAD, 6.18 M (20.3 FT) WEST OF THE MARK--SW 7 RM 1, 6.46 M (21.2 FT) SOUTHEAST OF THE MARK--SW 7 RM 2. THE MARK IS 0.30 METERS NE FROM A WITNESS POST THE MARK IS 0.30 M ABOVE THE ROAD.
Control Text
- 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 orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in June 1991.
- The Laplace correction was computed from DEFLEC99 derived deflections.
- 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.
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