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#1
Rob

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Does any one know the parameters to define the GGN 1993?

Either a projection type file or just the numbers.

thanks.

rob

#2
frax

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do you have a more full name for the projection?
Hugo Ahlenius
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#3
Hans van der Maarel

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Rob,

I have parameters for the following projections:
- Guam63 lat/lon degrees
- Guam, referenced to Clarke 1866, meter

Would it be any of those?
Hans van der Maarel - Cartotalk Editor
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#4
Rob

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thanks hans for your effort,

turns out that the Guam Geodetic Datum 1993 is Guam's nomenclature for HARN NAD 83 (esri has it as "NAD 1983 HARN Guam Map Grid.prj" which is in meters (and that should be changed to GGD1993 in the next Arc release for less confusion). My confusion was that the map provided to me was in GGD93 feet, which to me seems quite awkward given that the CS is defined in meters. I guess they might have wanted the added precision by surveying in feet rather than meters? Any Guam surveyors out there to explain this?

We all get lazy working in our own local CS's, I know....but....

To an interconnected global cart world.... cheers....

rob




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