			Aeromagnetic Surveying in Wisconsin 1996:
				Digital Data Files 


					By



				Stephen L. Snyder




		U.S. Geological Survey Open-File Report 00-500

					2000




U.S. Department of the Interior
U.S. Geological Survey

Aeromagnetic Surveying in Wisconsin 1996: Digital Data Files
By Stephen L. Snyder



This CD-ROM contains aeromagnetic data for 3 areas in northwestern Wisconsin
flown by the U.S. Geological Survey between August 1996 and September 1996.
The survey was flown using a USGS-owned Fairchild Helio-Porter Short Take-Off
and Landing (STOL) aircraft draped to topography at an average elevation of
500 feet (152 m) above ground.  Flightlines of the aeromagnetic survey were
oriented in a north-south direction at a spacing of 1/2 mile (805 m).  No tie
lines were flown. The three blocks of the survey required a total of about
6,700 line-miles (10,780 line-km) of flying. 

The aeromagnetic data on this CD-ROM include: (1) Point measurements taken
at 1/2-second intervals, giving 16 fields of data in ASCII format, including
flightline number, latitude, longitude, diurnally-corrected magnetic intensity,
residual (DGRF-removed) magnetic intensity, time, and altitude, (2) Grids of
residual magnetic intensity using a Lambert Conformal Conic projection and
given in several file formats, and (3) images of the aeromagnetic data and an
index map, each given in 5 graphics formats.

Files on this CD-ROM disc were generated on a PC under the Microsoft Windows 98
operating system and are most easily accessed by a PC using one of the common
Windows operating systems.  However, the folders and files are arranged such
that the information and data may be accessed from a larger variety of computer
systems.

A more complete description of the data is presented in file wisc1996.pdf,
an Adobe Portable Document File (PDF), and as an equivalent file, wisc1996.doc,
a Microsoft Word 2000 document. Both files contain imbedded color images of
the magnetic field for this survey.  To view the PDF document requires the
Adobe Acrobat Reader software. It is a free viewer that has been downloaded
from the Adobe web site and included on this disc.  The text without images
is also given in ASCII , as file wisc1996.txt which may be viewed in other
DOS or Windows readers. 

Sufficient hard disk space is needed to accommodate the ASCII point data
files which range in size from 12.4 to 36.0 megabytes (mb). The minimum
added requirements of the Acrobat reader for a Windows 95/98 installation
is about 10 mb of hard disk space.   This CD-ROM disc was produced in
accordance with the ISO 9660 standard. 

-------------------------------------------------------------------------------
U.S. Geological Survey Open-File Report 00-500

Although all data and software released on this CD-ROM have been used by
the USGS, no warranty, expressed or implied, is made by the USGS as to the
accuracy of the data and related materials and (or) the functioning of the
software.  Any use of trade, product, or firm names is for descriptive purposes
only and does not imply endorsement by the U.S. Government.

