This Folder:  cmpressd\
This File:    read_4th.txt


Report Title:     Aeromagnetic Surveying in Wisconsin 1998-99:
                     Digital Data Files
Report Authors:   Robert E. Bracken and Suzanne W. Nicholson
Report Document:  U.S. Geological Survey Open-File Report 99-527



Description of This Folder and Its Content:


This folder contains a compressed form of the line-data files.
It is designated by the following path:

\data\line\cmpressd\


In this folder, you will find the following sub-folders and
files:

cmprpgms\  Contains programs and instructions for uncompressing
           the binary (.bin) files found in this folder.

format.    A format-information file giving details of the ASCII
           formatting found in the line-data files.  The same
           file is found in the info\ folder.  This formatting
           information applies to the original ASCII line-data
           files produced by uncompressing the binary (.bin)
           files found in this folder.

lnc01.bin  A COMPRESSED form of the original line-data files
lnc02.bin  containing the aeromagnetic flight-line data sampled
lnc03.bin  at a 1/10-second interval.  These files must be
lnc04.bin  uncompressed to produce the original ASCII line-data
lnc05.bin  files.  The resulting ASCII files are described in the
lnc06.bin  format. file and in the other information given in the
lnc07.bin  info\ folder.  Specifics of the uncompression process,
lnc08.bin  including programs, are given in the cmprpgms\ sub-
lnc09.bin  folder.  The file names of the .bin line-data files
lnc10.bin  follow the rules given in "format."  The first 5
lnc11.bin  characters of the .bin file names correspond to the
lnc12.bin  related ln_NN.txt files in the info\ folder.  The
lnc21.bin  uncompressed .asc files will be about 13 times larger
lnc31.bin  than their compressed versions, averaging 150 Mb each.


read_4th.  (This file.)  Contains information describing this
           folder and its contents.