Research Guides: Cartographic Resources, Maps, and Spatial Data: Locating Maps

Geologic maps

Geologic Atlas of the United States
The Geologic Atlas of the United States is a set of 227 folios published by the U.S. Geological Survey between 1894 and 1945. Each folio includes both topographic and geologic maps for each quad represented in that folio, as well as description of the basic and economic geology of the area. The Geologic Atlas collection is maintained by the Map & GIS Library within the Texas A&M University Libraries.
National Geologic Map Database - Catalog Search | USGS
Search for geologic or geoscience maps by Keywords, Themes (geologic characteristics), Location (place name, bounding coordinates), Miscellaneous (map scale, publication date, format), or Publisher
State Geologic Surveys | AASG
From the Association of American State Geologists (AASG), click on any state to be linked directly to the state geologic survey.
Geological Maps from Delaware Geological Survey
From DGS Publications
DGS Publications | The Delaware Geological Survey
The Delaware Geological Survey (DGS) was established by the General Assembly in 1837 and reestablished in 1951. The Survey's mission is, by statute, geologic and hydrologic research and exploration, and dissemination of information through publication and public service.

Topographic Maps

Topographic maps portray elevations and geographic positions for both natural and man-made features. These are often used as a basic reference map.

Topographic quadrangles, also known as topo quads or "topos", are typically produced for a region or nation using a standard set of map scales and dimensions. These sets may be referred to by their scale or by the number of minutes or degrees of latitude/longitude which each sheet covers. For example, USGS topographic quadrangles at a scale of 1:24,000 are also referred to as 7.5 minute quads.

Print collection at Morris Library

The Maps collection in the lower level includes 7.5-minute topographic maps of Delaware, Maryland, New Jersey, and Pennsylvania. Please ask at the Student Multimedia Design Center desk for assistance. The earlier 15-minute topographic maps of these states are housed in Special Collections.

Delaware has unique topographic map products, linked from the State Map & Data tab.

US Topo Maps for America | USGS
US Topo maps are produced by the National Geospatial Program of the U.S. Geological Survey (USGS). First launched in 2009, US Topos combine the familiar look and feel of legacy paper USGS topographic maps with technological advances of the 21st century. US Topo map data is derived from the geographic information system (GIS) data of The National Map and is continuously updated via National, state, local, and commercial partnerships.
more...less...
The term “US Topo” refers specifically to quadrangle topographic maps published in 2009 and later. These maps are modeled on the familiar 7.5-minute quadrangle maps of the period 1947-1992, but are mass-produced from national GIS databases on a repeating cycle. US Topo maps repackage geographic information system (GIS) data in traditional map form; this benefits non-specialist map users, as well as applications that need traditional maps.
Historical Topographic Maps | USGS
The goal of The National Map’s Historical Topographic Map Collection (HTMC) is to provide a digital repository of USGS 1:250,000 scale and larger maps printed between 1884 and 2006.