Techniques and Methods 11–B3
The U.S. Geological Survey (USGS) is scanning, cataloging and georeferencing all scales and all editions of approximately 200,000 topographic maps published by the USGS since the inception of the topographic mapping program in 1884. This effort will provide a comprehensive digital repository of USGS topographic maps that are easily discovered, browsed, and downloaded by the public at no cost.
Historical maps are an important national resource because they provide the long-term record and documentation of the natural, physical, and cultural landscape. The history documented by this collection and the analysis of distribution and spatial patterns is invaluable throughout the sciences and nonscience disciplines. Genealogists, historians, anthropologists, archeologists and others use this collection for research, as well as for a framework on which a myriad of information can be presented in relation to the landscape. Topographic maps originally were produced to support minerals exploration, but they quickly became popular with many other disciplines and with the general public because of their usefulness for viewing and studying the Nation’s vast landscape. For more than 130 years, the USGS topographic mapping program has accurately portrayed the complex geography of our Nation through maps using the lithographic printing process.
Digital maps are georeferenced (tied to a known earth coordinate system) to provide for basic map analysis, such as distance and area calculation, and for coordinate readouts. Two georeferenced digital formats are used for distribution of the maps: (1) Portable Document Format (PDF) with a geospatial extension that is called Georeferenced PDF (GeoPDF®); and (2) Tagged Image File Format (TIFF) with an accompanying transformation file in Extensible Markup Language (XML) readable by open-source and proprietary Geographic Information Systems (GIS).
This report provides standards for the georeferenced maps, including data sources, file formats, file resolution, datums and projections, georeferencing, data quality, metadata content descriptions, and supporting documentation. In digital form, and with the added benefit of georeferencing, the maps become a versatile document that can be viewed individually, or viewed together across large areal extents.
First posted September 9, 2011
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This report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.
Allord, G.J., and Fishburn, K.A., 2011, Standards for scanned U.S. Geological Survey historical topographic quadrangle collection: U.S. Geological Survey Techniques and Methods, book 11, sec. B, chap. 3, 14 p.
Acronyms and Abbreviations
Appendix A: Notes and Discussion