Petersville mining district electromagnetic and magnetic airborne geophysical survey, data compilation
Dates
Publication Date
2015
Start Date
1996
End Date
2015
File Modification Date
2016-08-19 13:08:00
Citation
Burns, L.E., Fugro Airborne Surveys Corp., Stevens Exploration Management Corp., and Graham, G.R.C., 2015, Petersville mining district electromagnetic and magnetic airborne geophysical survey, data compilation: Alaska Division of Geological & Geophysical Surveys, http://dx.doi.org/10.14509/29445.
Summary
This publication, GPR 2015-3, contains geophysical data produced from airborne surveys conducted in 1996 and released in 1997 for 415 sq miles of the Petersville mining district, Alaska by the Alaska Division of Geological & Geophysical Surveys (DGGS). Aeromagnetic and electromagnetic data were acquired during the helicopter-based surveys. During 2004, the same digital data were reformatted for ease of use with modern processing tools, vector files and the 56,000 Hz resistivity grid, were added, and new color maps were produced. Except for leveling of the 56,000 Hz coplanar resistivity grid, no reprocessing of the geophysical data was done. The files represent the end part of the 2004 process. A few maps produced in 1997, such as flight [...]
Summary
This publication, GPR 2015-3, contains geophysical data produced from airborne surveys conducted in 1996 and released in 1997 for 415 sq miles of the Petersville mining district, Alaska by the Alaska Division of Geological & Geophysical Surveys (DGGS). Aeromagnetic and electromagnetic data were acquired during the helicopter-based surveys. During 2004, the same digital data were reformatted for ease of use with modern processing tools, vector files and the 56,000 Hz resistivity grid, were added, and new color maps were produced. Except for leveling of the 56,000 Hz coplanar resistivity grid, no reprocessing of the geophysical data was done. The files represent the end part of the 2004 process. A few maps produced in 1997, such as flight line maps and resistivity maps produced as bluelines, are not reproduced; however, color versions of these data and the data enabling production of these maps are included in this archive. Data provided in GPR 2015-3 include processed (1) linedata ASCII databases, (2) gridded files of magnetic and resistivity data, (3) vector files of data contours, interpreted electromagnetic anomalies, and flight lines, and (4) plot files of selected full-color maps, and (5) an Adobe Acrobat file showing the 56,000 Hz gridded data. A vector file of the interpretation overlay produced by the Contractor for the Petersville data (released previously on paper as DGGS Public Data File 97-8) is also included. All maps produced during 2004 are at a scale of 1:63,360 and are included in HPGL2 (*.prn), Adobe Acrobat (.pdf), and postscript (*.ps) format.
DGGS geophysics datasets are typically compilations of multiple digital data file formats. These formats may include: GeoTiff, ESRI shapefile, Geosoft binary grid (GRD), Microsoft Office documents, PDF, ER Mapper ERS, ASCII text files (including CSV), Geosoft ASCII grid (GXF), Geosoft database, AutoCAD DXF, Geosoft plot file (PLT), Printer files (HPP, PRN, or other), digital images (multiple formats), digital video (multiple formats), Geosoft ASCII XYZ, Geosoft ASCII files (PLY, i0, EXP), and KMZ
The 1996 Petersville survey and this current project are part of the Alaska Airborne Geophysical/Geological Mineral Inventory project funded by the Alaska State Legislature and managed by State of Alaska, Department of Natural Resources (DNR), Division of Geological & Geophysical Surveys (DGGS). The project seeks to catalyze private-sector mineral development investment. The project delineates mineral zones on Alaska state lands that: (1) have major economic value; (2) can be developed in the short term to provide high quality jobs for Alaska; and (3) will provide economic diversification to help offset the loss of Prudhoe Bay oil revenue. The purpose of the 2004 project was to upgrade the digital data formats and improve the map formats for the early detailed airborne geophysical surveys produced by DGGS as part of the Alaska Airborne Geophysical/Geological Mineral Inventory project and to provide these improved products to the public. Various items, such as color geophysical maps produced with raster topography, were not technically possible at time of the original data release. Various other digital files of use to the customer were also not accessible to the public for the older surveys.
