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1992-1994 USGS Digital Orthophoto Quarter Quadrangles
Dataset Basics A Digital Orthophoto Quadrangle (DOQ) is a computer-generated image of an aerial photograph in which the image displacement caused by terrain relief and camera tilt has been removed. The DOQ combines the image characteristics of the original photograph with the georeferenced qualities of a map. The standard DOQ’s produced by the U.S. Geological Survey (USGS) are either grayscale or color-infrared (CIR) images with a 1-meter ground resolution; they cover an area measuring 3.75- minutes longitude by 3.75-minutes latitude, approximately 5 miles on each side or a quarter of a USGS 7.5 minute quad. This dataset was provided to IU by the Natural Resources Conservation Service (NRCS), a component of the US Department of Agriculture. Availability While the spatial extent of this dataset is state-wide, it does not cover the entire state. To view the location of quadrangles available for this dataset, please download this map (.pdf) File Formats Coordinate System: UTM, Zone 16 North File Format: GeoTiff (~40MB/file) File Format: MrSID MG2 (~2 MB/file) Original File Format: BSQ (45 MB/file) File Format: JPG - not georeferenced
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