For my thesis, I digitized and manipulated various geologic maps provided by the USGS. Many of these areas did not have shapefile data, so I used available jpeg and tif images. I georeferenced these maps in ArcGIS Pro and traced the outlines of geologic units, creating my own polygon feature classes and attribute tables for each map. I exported the resulting maps as pdfs and imported them into Adobe Illustrator to add the unit descriptions.