For those who wish to try and make such a map, here is an excellent (postscript) page with documents explaining and showing geological mapping symbols at the USGS site.
Digital Cartographic Standard for Geologic Map Symbolization
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Printable View
For those who wish to try and make such a map, here is an excellent (postscript) page with documents explaining and showing geological mapping symbols at the USGS site.
Digital Cartographic Standard for Geologic Map Symbolization
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And here is the FGDC standard.
FGDC Digital Cartographic Standard for Geologic Map Symbolization
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