ò BYU Department of Geology

       MAP COLLECTIONS

Ohio Code

    In the United States 1º x 1º sections have been broken down into 64 7.5' quadrangles.  Each quadrangle is given a code using the latitude and longitude of the southeast corner of the 1º grid.  The quadrangle is also identified by a letter corresponding to the row in which it lies within the 1º grid  and a number corresponding to the column.  Letters range from A to H increasing to the North.  Column numbers increase from East to West.

Example:

The Ohio Code for a quadrangle two rows from the top and three rows from the left is 40111G6.