Liberty Bell area, western Bonnifield mining district, electromagnetic and magnetic airborne geophysical survey, data compilation
Dates
Publication Date
2017
Start Date
2001
End Date
2017
File Modification Date
2017-03-07 12:40:00
Citation
Fugro Airborne Surveys, Stevens Exploration Management Corp., Burns, L.E., and Graham, G.R.C., 2017, Liberty Bell area, western Bonnifield mining district, electromagnetic and magnetic airborne geophysical survey, data compilation: Alaska Division of Geological & Geophysical Surveys, http://doi.org/10.14509/29690.
Summary
This publication, GPR 2017-1, provides geophysical data produced from an airborne geophysical survey conducted in 2001 and released in 2002 for 276 sq miles of the Liberty Bell area, western Bonnifield mining district, central Alaska. Aeromagnetic and electromagnetic data were acquired during the survey. During 2016, the same digital data were reformatted for ease of use with modern processing tools; vector shapefiles and the analytic signal and calculated first vertical derivative grids were added. Other than the creation of calculated grids, no new processing was done. Data provided in GPR 2017-1 include processed (1) linedata ASCII databases, (2) gridded files of magnetic and resistivity data, (3) vector files of data contours, [...]
Summary
This publication, GPR 2017-1, provides geophysical data produced from an airborne geophysical survey conducted in 2001 and released in 2002 for 276 sq miles of the Liberty Bell area, western Bonnifield mining district, central Alaska. Aeromagnetic and electromagnetic data were acquired during the survey. During 2016, the same digital data were reformatted for ease of use with modern processing tools; vector shapefiles and the analytic signal and calculated first vertical derivative grids were added. Other than the creation of calculated grids, no new processing was done. Data provided in GPR 2017-1 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, (4) plot and PDF files of previously published full-color maps, and (5) proof sheet containing a reduced size version of all previously published maps for this project. Data provided include processed line data, gridded files derived from the line data, and vector files of data contours derived from the gridded files for the appropriate data systems. Interpreted electromagnetic anomalies are also included as vector files. Data are described in more detail in each folders *readme.txt files included in each folder. There is also more description in the final project report (GPR2002-9) included in the documents folder/download.
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 2001 Liberty Bell survey and this 2017 update 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 2017 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.
