Last revised: August, 2008
Brief Guide to the Map Collection
Scope:This Guide will give a brief description of items in the Map Collection in McKeldin Library. Call the U.S. Government Information, Maps & GIS Services Staff at 301-405-9165 for more information.
Table of Contents
Background
As a Regional Federal Depository Library, the U.S. Government Information, Maps & GIS Services unit of McKeldin Library collects and maintains maps and charts produced and made available by the Federal Depository Library Program. The Map Collection is home to approximately 350,000 items, primarily from U.S. Government sources. Coverage includes all U.S. states, most U.S. territories and possessions, and some areas outside the U.S. A brief description of items in the Map Collection follows.
Bureau of Land Management Maps (BLM)
Produced by the Land Management Bureau (formerly Bureau of Land Management), these are cadastral survey maps of U.S. public (primarily western United States) lands. The scale is 1:100,000. Our collection begins around 1980.This set is made up of two series:
- Surface Management Series
show ownership of public, federal, and state lands. - Surface and Mineral Management Series
show the federal ownership of minerals as well as the ownership of public, federal, and state lands.
CIA Maps
Produced by the Executive Office of the President, these are planimetric maps of countries and regions, although some thematic maps are included in this series. The maps show very little detail, and scales vary. Larger CIA Maps are in the Map Collection. The coverage is worldwide, but some maps have not been updated in the last fifteen years, in particular maps of countries primarily in southern Africa and South America.
Maps produced in 1992 or later are accessible in the Catalog.
DMA Topographic Maps
Produced by the Defense Mapping Agency, these are topographic maps of the United States with a scale of 1:250,000. They contain the same information as USGS Topographic maps. This series of maps is not current; most of these maps are 45 years old.
USFS Topographic Maps
The United States Forest Service topographic maps are USGS maps adapted by the U.S. Department of Agriculture, Forest Service. These maps are 7.5 minute topographic maps which cover the U.S. National Forests. They contain roughly the same information as the USGS topographic maps. Maps produced after 1992 are listed in the Catalog. In order to find them, do a keyword search using the name of the "forest."
Note: THE USFS Topographic Maps are now interfiled with the USGS Topographic maps.
USGS Thematic Maps
These maps are produced by the Department of the Interior and are primarily geologic in nature. They are indexed in the Guide to USGS Publications (U.S. Government Information Reference Z 6028.G831).
The Map Collection has the following series:
- Coal Investigation Maps (C)
Scales vary. These show bedrock geology, stratigraphy, and structural relationships within the areas mapped. (I19.85:) - Geophysical Investigations Maps (GP)
Scales vary. These show the results of surveys to measure geomagnetism, radioactivity, and gravity of selected areas of the country (I19.87:) - Geologic Quadrangle Maps (GQ)
Scale 1:24,000 for most maps. These show the bedrock, surficial, or engineering geology of selected quadrangles in the United States. Accompanied by brief texts. (I19.88:) - Hydrologic Investigations Atlases (HA)
Scales vary. Show a variety of water resources information such as: depth to ground water, floods, irrigated acreage, producing aquifers, availability of water on Indian lands, surface-water discharge to the oceans, chemical or mineral content of water, surface impoundments, and water temperature. (I19.89:) - Miscellaneous Geologic Investigations Maps (I)
Formerly called Miscellaneous Investigations Maps. Scales vary. Show a variety of geologic and hydrologic topics. Maps of the planets and moons are found here. - Land Use and Land Cover Maps (L)
Scale 1:250,000 for most maps; some are 1:100,000. Land use refers to human uses of the land (i.e. housing and industry). Land cover describes the vegetation, water, natural surface, and construction on the land surface. Features of base maps are boundaries, cities and towns, railroads, roads and highways, rivers, and lakes. (I19.112:) - Miscellaneous Field Studies (MF)
Scales vary. Preliminary reports on geologic aspects of mineral and environmental studies. Series, begun in 1950, formerly known as Minerals Investigations Field Studies. Pre-1971 maps show geology related to specific mining or mineral deposit studies. Post-1971 maps cover subjects related to environmental studies or wilderness areas mineral investigations. (I19.113:) - Mineral Investigations Resource Maps (MR)
Scales vary. Geographic distribution and grade of metallic and nonmetallid minerals. (I19.90:) - Oil and Gas Investigations Charts (OC)
Scales vary. Show subsurface stratigraphic information for certain oil and gas fields and of other areas of hydrocarbon potential. (I19.92:) - Oil and Gas Investigations Maps (OM)
Scales vary. Show the area of certain oil and gas fields. In addition, maps show surface geology and subsurface stratigraphy and geologic structure. (I19.93:)
USGS Topographic Maps
These maps are produced by the Department of the Interior, United States Geological Survey (USGS). USGS topographic maps include physical features such as elevations, mountains, lakes, rivers, buildings, and transportation routes. The Map Collection has three series of these maps:
- 7.5 minute maps
Scale of 1:24,000. This is our largest set of maps, making up 70% of the collection. Coverage is for the United States including U.S. territories and possessions. These maps are indexed in Index to Topographic and Other Map Coverage (U.S. Government Information Maps I19.41/6-3:) which is arranged by state, with a separate index for U.S. territories. When requesting these maps, note the state and quadrangle name. The Omni Gazeteer of the United States of America (U.S. Government Information Maps E154.O45) also lists the quadrangle name. - Alaska topographic maps
Scale of 1:63,360 (one inch = one mile). - 30 x 60 minute maps
Scale of 1:100,000. The Map Collection has maps from 1985 to the present and has some coverage of every state in the U.S.
Aeronautical Charts
These charts are produced by the Defense Mapping Agency Aeronautic Center (DMAAC). We have the latest editions of these charts, which are available in four series:
- 1:500,000 TPC Tactical Pilotage Chart
- 1:1,000,000 ONC Operational Navigational Chart
- 1:2,000,000 JNC Jet Navigational Chart
- 1:5,000,000 GNC General Navigation and Planning Chart
Airport Obstruction Charts
Show details of areas surrounding airports. They are produced by the National Ocean Service (NOS which is part of NOAA. The scale is 1:12,000. A quarterly list outlines the dates of the latest editions available. All airport obstruction charts have the call number stem of C55.411/3:OC followed by a one- to four-digit number. Use the Catalog to find the airport number following the stem by doing a word search using the official name of the airport along with the words "obstruction chart."
Nautical Charts
Nautical charts are produced by two agencies: the Defense Mapping Agency, Hydrographic-Topographic Center (DMAHTC) and the National Ocean Service (NOS).
The DMA nautical charts show details of navigable water bodies throughout the world. The scales vary.
NOS charts cover nautical chart Region I, which is primarily the U.S., along with Puerto Rico and the Virgin Islands. Scales vary.
Both sets of nautical charts are indexed in the Catalog of Maps and Charts and Related Products (Part II) (US Government Information Atlas GA359 .U54 1992). They are identified by a five-digit numerical ID. Both sets of charts have the same identification scheme; ID codes of less than five digits indicate large bodies of water. There is some Catalog coverage for these charts.
