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Benchmark recovered but not in USGS/NGS Database


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We were up on Coosa Bald in North Georgia for a SOTA activation and I found a USGS benchmark disk stamped COOSA 1934.  However, this particular mark is not listed in the USGS database by name and does not appear on the benchmark map.


Could this mark have possibly been forgotten about or the reference sheet lost years ago?  There is another mark listed with the name COOSA, but it is located in Rome, GA, monumented in 1972, and is nowhere near the summit we were on.


There also appears to be a COOSA 1873 that was located in Rome, and replaced by the COOSA above when it was not recovered.


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There are many USGS disks that were not included in the US Coast and Geodetic Survey (now National Geodetic Survey) data base that is on line. USGS data was never computerized.

They were not included because either the data was not submitted to US CGS, or only collected to mapping accuracy and not to geodetic accuracy standards and methods.

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The U.S. Geological Survey (USGS), an agency in the Dept. of the Interior has the responsibility for producing our national topographic maps. They completed the monumental task of complete national mapping of the 1:24,000 scale map series (about 55,000 maps) in the early 1990's. USGS would often set survey monuments to help "control" the map. Maps are produced from aeronautical photos mosaiced together. In order to provide accurate location, orientation, scale and elevation to a flat map of a curved surface, it is required to have numerous points that can be identified on the photographs for which the coordinates/elevations are well known. The marks set by USGS were a vital part of this operation. In the days when mapping surveys were conducted primarily by line-of-site methods, these marks helped save money by helping to ensure a network that cartographers could rely on for mapping update procedures. With the rapid developments in surveying and mapping technology, especially GPS, USGS sees little need to setting new marks or maintaining the old networks. Unfortunately the data for tens of thousands of these marks set by USGS were never submitted to NGS for inclusion in the National Spatial Reference System. Due to major reductions in staff and the changing nature of mapping requirements, it is highly unlikely that USGS will ever automate these data.

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