Open-File Report 99-028
Aeromagnetic Surveying in Wisconsin 1997-98: Digital Data Files 
By David L. Daniels, Suzanne W. Nicholson, and William F. Cannon

Directory "grids"

The point data have been interpolated into binary raster USGS style grids (file extension .grd)
by using a minimum curvature gridding algorithm (program MINC, Phillips, 1997). 
ASCII versions of the USGS grids are also given (.agd). USGS grids and binary point files 
can be manipulated using USGS (DOS) software for the PC (Phillips, 1997). 
This is freeware that is included in the usgs_pf directory. Two alternate ASCII file formats
are also included. These ASCII grids permit importation into other software packages. 
Files with extension .arc can be imported into Arcview, and file extension .gxf can be imported 
into several programs including ER Mapper and Geosoft Oasis Montaj.

Download either the separate files or the compressed files.