Chris served as the topoView development lead. Over the last decade, he's been focused on improving the accessibility of geologic map data to the public. New functionality driven by your feedback The latest version of topoView is full of enhancements based on hundreds of your comments and suggestions. We've added the ability to preview maps within the interface and give you tools to compare any historical map with maps of the present.
Filters and searches work seamlessly with the map records table to get you the info you need with fewer clicks.
Accessing the information you need is easier and quicker than ever. Search Search. Mapping, Remote Sensing, and Geospatial Data. Most applications have an option for toggling on map indices showing an outline of all the maps, though you must zoom in to see the lines: Map Locator on the USGS Store -- Search and download free digital maps in GeoPDF format or order paper maps. Apply Filter. TopoView - Click on any of the round map scale indicators on the right side of the map.
The National Map Viewer - Click on the What is a topographic map? The distinctive characteristic of a topographic map is the use of elevation contour lines to show the shape of the Earth's surface.
Elevation contours are imaginary lines connecting points having the same elevation on the surface of the land above or below a reference surface, which is usually mean sea level. Contours make it possible to show the How do I get a full-scale plot of a ,scale 7. There are three ways to get full-scale plots of USGS topographic quadrangle maps, including both Historical Topographic maps produced and US Topo maps produced present.
Download the GeoPDF map file and send it to a local printing How current are US Topo maps? US Topo maps are updated on a three-year production cycle maps covering one third of the country are updated each year. The US Topo production schedule follows the U. This does not include US Topos for Alaska, which are on a different schedule. Are USGS topographic maps copyrighted? All topographic maps produced by the U.
Geological Survey USGS are in the public domain and are not copyrighted except for the following three cases that apply only to US Topo maps produced present : Most maps in the period contain commercially licensed road data see note below. Orthoimages in Alaska are commercially licensed How accurate are US Topo maps, and why don't they have an accuracy statement?
US Topo maps are as accurate as the data sources used to make them, but because these sources are many and varied, it is not possible to make a single simple statement that the map as a whole meets a particular level of accuracy. US Topo maps, therefore, do not have a traditional accuracy statement in the map collar. Please note, the viewer functions best when using Chrome or Firefox. IE users may experience limited functionality.
To view a listing of all quad map files by 1-degree block, click here. US Topo: Maps for America. Topo Maps. Year Select Year Apply Filter. Historical Topographic Maps - Preserving the Past. Filter Total Items: 2. Davis, Larry R. View Citation. Davis, L. Geological Survey Techniques and Methods book 11, chap.
B2, 20 p.
0コメント