Search results
Results from the WOW.Com Content Network
DOQs produced by the USGS cover an area measuring 7.5-minutes longitude by 7.5-minutes latitude (the same area covered by a USGS 1:24,000-scale topographic map, also known as a 7.5-minute quadrangle) or 3.75-minutes by 3.75-minutes.
From approximately 1947–1992, the USGS produced the 7.5 minute series, with each map covering an area one-quarter of the older 15-minute quad series, which it replaced. [1] A 7.5 minute quadrangle map covers an area of 49 to 70 square miles (130 to 180 km 2 ). [ 2 ]
Topographic maps are also commonly called contour maps or topo maps. In the United States, where the primary national series is organized by a strict 7.5-minute grid, they are often called or quads or quadrangles. Topographic maps conventionally show topography, or land contours, by means of contour lines.
The National Map is a significant contribution to the U.S. National Spatial Data Infrastructure (NSDI) from the Federal Geographic Data Committee (FGDC) and currently is being transformed to better serve the geospatial community by providing high quality, integrated geospatial data and improved products and services including new generation ...
Each map was bounded by two parallels and two meridians spaced 15 minutes apart—the same area covered by four maps in the 7.5-minute series. The 15-minute series, at a scale of 1:63,360 (one inch representing one mile), remains the primary topographic quadrangle for the state of Alaska (and only for that particular state).
7.5-minute 30-minute Created by autocorrelation or manual profiling from aerial photographs May be derived from a wide variety of sources using any of a number of USGS approved techniques and instrumentation Level 2 All series Created from digital line graph (DLG) contours or equivalent, from any USGS map series up to 1:100000 scale
GIS data for State of Kentucky; Name Description; Kentucky Geography Portal: The Kentucky Geoportal is a Data Clearinghouse that provides ays to discover and share geospatial data resources. Locate maps and geographic data content for a particular part of the state or search based on keyword or theme type. [12] Kentucky Open Data Portal
From 1958, a number of town maps at scales of 1:5,000 or 1:10,000 were also made, initially on the Gauss-KrĪger projection, but after 1970 on a stereographic projection. More than 100 such sheets have been produced. There is also a street map of Bucharest in four sheets at 1:15,000 derived from larger-scale surveys, which is revised annually.