One of the most time-consuming parts of building maps is finding the data sets you want. I’m often forgetting where I found different datasets, and I wanted to share some of the ones I like to go back to.
USGS National Map
Mineral Resources Online Spatial Data:
Purdue’s GIS Data by State
A concise list of important resources available to you on the web and at Purdue. https://guides.lib.purdue.edu/c.php?g=353290&p=2378621