DGGS Staff 2016 digital data Digital Data Series DDS 12 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys http://doi.org/10.14509/29555 Merged grids of residual magnetic intensity and apparent resistivity compiled from the East Styx, Farewell, Middle Styx, and Styx River geophysical surveys. This electromagnetic and magnetic airborne geophysical survey data compilation is a product of the Alaska Division of Geological & Geophysical Surveys' (DGGS) Airborne Geophysical/Geological Mineral Inventory (AGGMI) program and the Alaska Strategic and Critical Minerals Assessment Capital Improvement Project. The goal of the Alaska Division of Geological & Geophysical Surveys' (DGGS) Airborne Geophysical/Geological Mineral Inventory (AGGMI) program is to enhance the understanding of Alaska's mineral resources and stimulate private-sector mineral development. The program seeks to delineate 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 Alaskans; and (3) will provide economic diversification to help offset the loss of Prudhoe Bay oil revenue. Candidate lands for this program are identified on the basis of existing geologic knowledge, land ownership, and nominations from Alaska's geologic community. The AGGMI program and resulting new geologic knowledge are recognized worldwide and have encouraged millions of dollars of venture capital expenditures in the local economies of the surveyed mining districts. These venture capital expenditures have led to discovery and delineation of new mineral resources. The multi-year Strategic and Critical Minerals Assessment Capital Improvement Project (SCMA) was established to determine Alaska's geologic potential for rare-earth elements and other minerals that are essential for our modern, technology-based society. This program began in FY2012 with a data survey and compilation of existing information on rare-earth-element occurrences in Alaska, and expanded significantly in FY2013 to include additional critical minerals, re-analyses of existing samples, and obtaining new field and analytical data, including airborne geophysics. >st_frl_mst_est: Geosoft format gridded data, ER Mapper format gridded data, ESRI ArcGIS shapefile, and keyhole markup language (.kml) data archive files. Note: these data are provided in both UTM Zone 5 - NAD27 and Geographic WGS84 projections. The data files were compiled from the East Styx, Farewell, Middle Styx, and Styx River geophysical surveys. 2007 2013 ground condition planned As needed -154.539294 -151.691417 62.529860 61.511703 ISO 19115 Topic Category geoscientificInformation Alaska Division of Geological & Geophysical Surveys Airborne Geophysical Survey Electromagnetic Data Electromagnetic Survey Geophysical Map Geophysical Survey Geophysics Geophysics Search Tag Gridded Data Magnetic Data Magnetic Survey Magnetics Alaska Division of Geological & Geophysical Surveys Alaska, State of This report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below). Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product. Alaska Division of Geological & Geophysical Surveys Metadata Manager mailing and physical

3354 College Road

Fairbanks AK 99709-3707 USA (907)451-5020 (907)451-5050 dggspubs@alaska.gov 8 am to 4:30 pm, Monday through Friday, except State holidays Funding for the originating geophysical surveys was provided by the Alaska Division of Geological & Geophysical Surveys' (DGGS) Airborne Geophysical/Geological Mineral Inventory (AGGMI) program and the Alaska Strategic and Critical Minerals Assessment Capital Improvement Project. The geophysical surveys were managed by State of Alaska, Department of Natural Resources (DNR), Division of Geological & Geophysical Surveys (DGGS). These merged grids were generated as part of the East Styx data collection contract. The survey data were collected, processed, and/or compiled by Burns, Laurel E., Graham, G. R. C., Stevens Exploration Management Corp., Anglo American Exploration (USA), Inc., Fugro Airborne Surveys Corp., Fugro GeoServices, Inc., CGG, Emond, Abraham M., Barefoot, John Delton. Geological Survey of Canada U.S. Geological Survey 2015 Canada Natural Resources Canada http://gdr.agg.nrcan.gc.ca/gdrdap/dap/index-eng.php?productid=1587 All originating data met contract specifications with a few exceptions due to difficult operational conditions. These exceptions did not noticeably impact data quality. Additional detail about contract specifications and operational issues can be found in the metadata of the originating surveys. These data originate from multiple similar geophysical surveys with different specifications. Reference the metadata of each originating survey for exact specifications. Helicopter and fixed wing geophysical surveys often have small data gaps that do not negatively impact the overall quality of the final products. Reference the metadata for each originating survey for specific details. All originating data were positioned by DGPS (Differential Global Positioning System) with an accuracy of 5 meters or better. Burns, L.E. CGG Fugro GeoServices, Inc. 2014 Geophysical Report GPR 2014-5 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys scale 1:63,360, 1 DVD http://doi.org/10.14509/29142 63360 paper 2014 publication date Burns, L.E. and others, 2014 Data collection, processing, and delivery Burns, L.E. CGG Fugro GeoServices, Inc. 2014 Geophysical Report GPR 2014-2 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys scale 1:63,360, 1 DVD http://doi.org/10.14509/27291 63360 paper 2014 publication date Burns, L.E. and others, 2014 Data collection, processing, and delivery Burns, L.E. Graham, G.R.C. Emond, A.M. Barefoot, J.D. 2019 Geophysical Report GPR 2019-12 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys 4 p http://doi.org/10.14509/30190 paper 2019 publication date Burns, L.E. and others, 2019 Data collection, processing, and delivery Burns, L.E. Fugro Airborne Surveys Corp. Fugro GeoServices, Inc. 2013 Geophysical Report GPR 2013-2 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys scale 1:63,360, 1 DVD http://doi.org/10.14509/25419 63360 paper 2013 publication date Burns, L.E. and others, 2013 Data collection, processing, and delivery Burns, L.E. Graham, G.R.C. Emond, A.M. Barefoot, J.D. CGG Fugro GeoServices, Inc. 2019 Geophysical Report GPR 2019-10 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys 21 p http://doi.org/10.14509/30188 paper 2019 publication date Burns, L.E. and others, 2019 Data collection, processing, and delivery CGG Fugro GeoServices, Inc. 2015 Geophysical Report GPR 2014-4 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys 22 sheets http://doi.org/10.14509/29349 paper 2015 publication date CGG and Fugro GeoServices, Inc., 2015 Data collection, processing, and delivery Burns, L.E. Emond, A.M. Fugro Airborne Surveys Corp. Stevens Exploration Management Corp. 2019 Geophysical Report GPR 2019-2 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys 3 p http://doi.org/10.14509/30166 paper 2019 publication date Burns, L.E. and others, 2019 Data collection, processing, and delivery Burns, L.E. Fugro Airborne Surveys Corp. Stevens Exploration Management Corp. Anglo American Exploration (USA), Inc. 2008 Geophysical Report GPR 2008-2 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys 5 sheets, scale 1:63,360 http://doi.org/10.14509/15981 63360 paper 2008 publication date Burns, L.E. and others, 2008 Data collection, processing, and delivery Burns, L.E. Fugro Airborne Surveys Corp. Stevens Exploration Management Corp. 2008 Geophysical Report GPR 2008-3 Fairbanks, Alaska, United States Alaska Division of Geological & Geophysical Surveys 27 sheets, 1 DVD http://doi.org/10.14509/16561 paper 2008 publication date Burns, L.E. and others, 2008 Data collection, processing, and delivery Gridded data - The gridded data from the East Styx, Farewell, Middle Styx, and Styx River geophysical surveys were merged. The diurnally corrected magnetic data for the Styx River area were adjusted for regional variations i.e. IGRF gradient, 2005, updated to the date of data acquisition and adjusted for altimeter variations. The East Styx, Farewell, and Middle Styx areas were adjusted using the 2010 IGRF model updated to the date of data acquisition and adjusted for altimeter variations. The residual grids of all the areas may, therefore, have different base values dependent on the IGRF model used because of the time elapsed between the flying of the first and last surveys. The grids were adjusted to each other prior to the final merge. The apparent resistivity grids for 56,000 Hz, 7200 Hz, and 900 Hz coplanar EM data were merged with no reprocessing, as general processing methods and more importantly background resistivity values for all frequencies have not changed since the Styx River (2007/2008) flying. The gridded data from the East Styx survey were merged with data from previous surveys flown in the Farewell and Middle Styx areas (2012 and 2013) and in the Styx River area (2007 and 2008) using Oasis Montaj techniques. Oasis Montaj has the capability to merge or stitch two or three grids together. The process requires overlap between adjacent grid areas. There is also the option of selecting different grid stitch techniques. For this project, the standard "Suture" technique with the "No De-trending" option was selected. The process requires selecting a "master" grid or the grid that all other grids will be leveled to. The grid that was published first is usually chosen and the grid from the most recent survey was selected as the secondary grid (i.e. the grid that will be DC shifted to the master grid). 2013 Boundary - DGGS staff constructed a boundary of the merged grid file. The grid boundary was constructed using Geosoft Oaisis montaj grid outline and map export functions. The boundary file is available in Geosft PLY ASCII format and ESRI Shapefile format. 2019 Google Earth KMZ files - DGGS staff created Google Earth KMZ/KML files from the grid files data using ESRI ArcGIS software. 2019 raster Universal Transverse Mercator 5 0.999600 -153 0 500000.000000 0 coordinate pair .00000001 .00000001 Meters North American Datum of 1927 Clarke 1866 6378206.40000000037 294.978698199999997 st_frl_mst_est Geosoft format gridded data, ER Mapper format gridded data, ESRI ArcGIS shapefile, and keyhole markup language (.kml) data archive files. Note: these data are provided in both UTM Zone 5 - NAD27 and Geographic WGS84 projections. The data files were compiled from the East Styx, Farewell, Middle Styx, and Styx River geophysical surveys. Alaska Division of Geological & Geophysical Surveys (DGGS) and contractor. st_frl_mst_est Alaska Division of Geological & Geophysical Surveys Metadata Manager mailing and physical

3354 College Road

Fairbanks AK 99709-3707 USA (907)451-5020 (907)451-5050 dggspubs@alaska.gov 8 am to 4:30 pm, Monday through Friday, except State holidays DDS 12 The State of Alaska makes no expressed or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product. DGGS publications are available as free online downloads or you may purchase paper hard-copies or digital files on CD/DVD or other digital storage media by mail, phone, fax, or email from the DGGS Fairbanks office. To purchase this or other printed reports and maps, contact DGGS by phone (907-451-5020), e-mail (dggspubs@alaska.gov), or fax (907-451-5050). Payment accepted: Cash, check, money order, VISA, or MasterCard. Turnaround time is 1-2 weeks unless special arrangements are made and an express fee is paid. Shipping charge will be the actual cost of postage and will be added to the total amount due. Contact us for the exact shipping amount. Contact DGGS for current pricing Geosoft format gridded data, ER Mapper format gridded data, ESRI ArcGIS shapefile, and keyhole markup language (.kml) data archive files http://doi.org/10.14509/29555 Free download 20190726 Alaska Division of Geological & Geophysical Surveys Simone Montayne Metadata Manager mailing and physical

3354 College Road

Fairbanks AK 99709-3707 USA (907)451-5020 (907)451-5050 dggspubs@alaska.gov 8 am to 4:30 pm, Monday through Friday, except State holidays FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 If the user has modified the data in any way they are obligated to describe the types of modifications they have performed in the supporting metadata file. User specifically agrees not to imply that changes they made were approved by the Alaska Department of Natural Resources or Division of Geological & Geophysical Surveys. http://www.dggs.alaska.gov/metadata/dggs.ext dggs metadata extensions