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My data: http://water.usgs.gov/GIS/dsdl/aquifrp025.tar.gz (USGS circa 2003 data on aquifers in the contiguous U.S.) Program: ArcGIS 10.1
The shapefile has no coordinate system or spatial reference. The metadata specifies NAD 1983 and in decimal degrees. My goal is to render this in such a way as to obtain 'normal' area/length/etc. values in meters for the purposes of calculating overlays with other spatial data. I cannot project the data because it has no coordinate system (error: no input coordinate system specified; paraphrasing)...batch/define doesn't work correctly either (the former same error, the latter (technically for use with rasters?) defines the projection, but reprojecting using the project tool doesn't do anything substantive (i.e. areas for huge swaths of the U.S. "46.1" etc. etc.).