Maps in this atlas are filed by quadrangle name. Preliminary Geologic Atlas of Pennsylvania Search the CAT for maps in our libraries. The USGS is developing a National Geologic Map Database . These maps are located in the EMS Library maps collection. The Maps Library in Paterno Library collects topographic maps for all 50 states.
Many topographic maps are now available online.
Various scales provided. TerraServer - View topographic maps, relief maps, and aerial photographs. Maptech MapServer - Search by place name. Various scales provided. The USGS maintains an online list of all its topographic maps.