Open-File Report 2009-1129
¹U.S. Geological Survey
²University of Kentucky, Lexington, KY
NURE Airborne Data Files and Formats
The majority of the files are organized by 1° x 2° quadrangle names. Some quadrangles are combined. Detail and regional areas can be found under (state name)_detail or (state name)_regional. Most quadrangles or areas contain four and sometimes five files. A few quadrangles have no data or just radiometric data and some regional areas have only magnetic data. Parts of Alaska were not flown. The files are:
(quad/area name)_mag.xyz The magnetic data file
(quad/area name)_rad.xyz The radiometric data file (often called the reduced file)
(quad/area name)_meta.txt The metadata file. File formats are included in the metadata files and are also listed below.
(quad/area name).jpg An image of the flight lines showing total field magnetics or, if not available, residual magnetics
(quad/area name).txt Not always present. Gives specific information about problems encountered in the specific data file(s).
The _mag.xyz and _rad.xyz files are g-zipped ASCII text files. They can be unzipped by using WinZip or most other zip programs. After unzipping, the suffix will be changed to just .xyz. The data files are space delimited. They can be viewed in a text editor and imported into most database/spreadsheet type programs.
Magnetic data file format:
Each line contains data in the following format, beginning with line 1 (no header included). Note: Alaska, detail areas, and miscellaneous files do not have resmagCM4:
Radiometric data file format:
Each line contains data in the following format, beginning with line 1 (no header included):