These resources provide free access to maps, map data, and research data from geology-related disciplines. You may also deposit your research data into some of them.
OpenBUBoston University's institutional repository housing scholarly works, research data, university publications and more
Earth ExplorerEarth Explorer allows you to search for digital elevation, Landsat, LiDAR, MODIS, Radar and more earth science data from the USGS and NASA. Registering for a free account is required if you wish to download data.
The National Geologic Map DatabaseThe National Geologic Map Database is the US Geological Survey's online library of over 90,000 maps and includes a glossary of place names.
Old Maps OnlineOld Maps Online is a collection of historic maps from around the world.
OneGeology PortalOneGeology Portal provides maps and data overlays for the entire globe, drawing on a community of researchers who provide the data.