Identification_Information: Citation: Citation_Information: Originator: Burns, L.E. Originator: Emond, A.M. Originator: GEONEX Aero Service Originator: Sanders Geophysics Ltd. Publication_Date: 2020 Title: Airborne magnetic geophysical survey of the Bethel basin, Alaska, data compilation Geospatial_Data_Presentation_Form: digital data Series_Information: Series_Name: Geophysical Report Issue_Identification: GPR 2020-12 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 8 p. Online_Linkage: http://doi.org/10.14509/30458 Description: Abstract: The airborne magnetic geophysical survey of the Bethel Basin, Alaska is located in the Bethel, Baird Inlet, Russian Mission, and Marshall quadrangles near the town of Bethel in southwest Alaska. Magnetic data were collected during October 1996 by Sanders Geophysics Ltd. and August 1994 by GEONEX Aero Service and its subsidiaries. A total of 20,915 line kilometers were collected covering 14,953 square kilometers. Line spacing was 800 meters (m). Data were collected using a fixed-wing aircraft with a median ground clearance of 90 m. The data, as well as additional metadata, are available from the DGGS website: http://doi.org/10.14509/30458. Purpose: These data were collected to assist the state in assessing the Bethel basin for natural gas potential. The aeromagnetic data were intended to be interpreted and integrated with available gravity, seismic, and geological information to recommend sites for subsequent drill testing of potential natural gas accumulations. Supplemental_Information: >ascii_data: ASCII format line data, other ASCII data >databases_geosoft: Geosoft format database of line data, other Geosoft format databases >documents: Project and field reports, survey background information, gridded data explanations, other supporting documentation >grids_ermapper: Geographically registered gridded data, ER Mapper ERS format >grids_geosoft: Geosoft-format binary grids, these grids can be viewed in ESRI ArcMap using a free plugin from Geosoft or using the free viewer available from Geosoft >images_registered: GeoTiff format images of all gridded data >kmz: Keyhole markup language (kml) kmz archive files of project data. Viewable in Google Earth and other compatible programs >maps_pdf_format: Printable maps in pdf format >vector_data: Line path, data contours, and survey boundary in ESRI shapefile (SHP) format, ESRI Geodatabase format, and/or AutoCAD dxf format Time_Period_of_Content: Time_Period_Information: Multiple_Dates/Times: Single_Date/Time: Calendar_Date: 1994 Single_Date/Time: Calendar_Date: 1996 Currentness_Reference: ground condition Status: Progress: complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -164.487505 East_Bounding_Coordinate: -160.510880 North_Bounding_Coordinate: 61.481451 South_Bounding_Coordinate: 59.712117 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Access_Constraints: 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). Use_Constraints: 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. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Data_Set_Credit: Funding was provided by the Alaska State Legislature. Cross_Reference: Citation_Information: Originator: DGGS Staff Publication_Date: 2014 Title: Airborne GeophysWeb: A compilation of geophysical data from DGGS and cooperating agencies Series_Information: Series_Name: Digital Data Series Issue_Identification: DDS 2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Online_Linkage: http://doi.org/10.14509/27222 Cross_Reference: Citation_Information: Originator: DGGS Staff Publication_Date: 2016 Title: Alaska merged geophysical data grids Series_Information: Series_Name: Digital Data Series Issue_Identification: DDS 12 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 3 p Online_Linkage: http://doi.org/10.14509/29555 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Geophysical data were acquired according to the contractor, contract, and request-for-proposals specifications. For additional detail about survey parameters, see the accompanying project report available in the documents directory of this data distribution package. Logical_Consistency_Report: Data originate from one company using the same contract specifications for all data. The originating coordinate system was retained for all publication products. Completeness_Report: This data set includes files that contain processed aeromagnetic measurements, electromagnetic measurements, altimetry measurements, and locational data for the entire survey area. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: These data are positioned with post-processed differential GPS. Discussion of grid resolution and factors that may impact the overall horizontal accuracy of the gridded data is available in the documents directory of this data distribution package. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Not applicable Lineage: Source_Information: Source_Citation: Citation_Information: Originator: DGGS Staff Originator: Sanders Geophysics Ltd. Publication_Date: 1997 Title: Total field magnetics of the southeastern Bethel basin, Alaska Series_Information: Series_Name: Public Data File Issue_Identification: PDF 97-27 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 6 sheets, scale 1:125,000 Online_Linkage: http://doi.org/10.14509/1776 Source_Scale_Denominator: 125000 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1997 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: DGGS Staff and Sanders Geophysics Ltd., 1997 Source_Contribution: Data collection, processing, and delivery Source_Information: Source_Citation: Citation_Information: Originator: Sander, S.D. Publication_Date: 1997 Title: Aeromagnetic survey, southwestern Bethel basin, Bethel, Alaska Series_Information: Series_Name: Public Data File Issue_Identification: PDF 97-28 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 32 p., 6 sheets, scale 1:125,000 Online_Linkage: http://doi.org/10.14509/1777 Source_Scale_Denominator: 125000 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1997 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Sander, S.D., 1997 Source_Contribution: Data collection, processing, and delivery Process_Step: Process_Description: Initial data collection, processing, and delivery - The airborne geophysical data were acquired under contract with GEONEX Aero Service, together with GEONEX Aerodat and GEONEX Resources, performed a high-sensitivity airborne magnetic survey on behalf of Zonge Engineering and Research Organization. The contractor's project report and other supporting documents are in the "documents" digital data package. They provide detailed documentation of the system specifications, data collection, processing, and delivery. Process_Date: 1994 Process_Step: Process_Description: Data collection, processing, and delivery - Sander Geophysics Limited conducted a high-sensitivity aeromagnetic survey. The survey was flown in October of 1996, in twenty-one production flights totaling 14, 628 line kilometers. The survey expanded upon an area surveyed in 1994 by Geonex Aero Services. The contractor's project report and other supporting documents are in the "documents" digital data package. They provide detailed documentation of the system specifications, data collection, processing, and delivery. Source_Used_Citation_Abbreviation: DGGS Staff and Sanders Geophysics Ltd., 1997 Source_Used_Citation_Abbreviation: Sander, S.D., 1997 Process_Date: 1997 Process_Step: Process_Description: Grid development - Missing residual magnetic intensity grid was created using Geosoft Oasis Montaj v9. The data channel Final Levelled was gridded with a cell size of 100 m, Blanking distance of 1600 m, and cells to extend beyond data set to one. The analytic signal grid was generated by using the analytic signal function in Geosoft Oasis Montaj v9 on the total magnetic field grid. The calculated first vertical derivative grid was created during the analytic signal process. The derivatives in the analytic signal calculation were computed using a fast Fourier transform (FFT) based 2D filter. Process_Date: 2019 Process_Step: Process_Description: RGB GeoTiff creation - RGB GeoTIFF raster files of gridded data were exported using Geosoft v9 by loading each Geosoft grid onto a map and using the map export tool. Process_Date: 2019 Process_Step: Process_Description: GeoPDF creation - Geospatial pdf file created using the Export Map function in Geosoft Oasis Montaj v9 with all maps layers visible. Process_Date: 2019 Process_Step: Process_Description: ER Mapper ERS Files - Data value ER Mapper ERS raster files were created using Geosoft v9 for the Geosoft format grids. The "Copy/Convert" toll under menu Grid and Image -> Utilities. File type "ER Mapper (*.ers) was chosen. Process_Date: 2019 Process_Step: Process_Description: Standard Boundary Polygon - The final boundary polygon was generated by loading the line data in Geosoft Oasis Montaj v9. The channel MAG was gridded using the Minimum Curvature option with the following settings: grid cell size = 25, blanking distance = 1600, cells to extend beyond data = 2. The polygon file was created using Grid Outline tool with edge resolution = 0.2. The polygon file was exported to ESRI shapefile. Process_Date: 2019 Process_Step: Process_Description: Keyhole markup language (kml) KMZ archive creation - Data were exported from Geosoft and ESRI ArcMap to kml format files and/or KMZ archives. These files were then combined and modified in Google Earth Pro to create the final KMZ file. Process_Date: 2019 Process_Step: Process_Description: Attributed Flight Path - An attributed ESRI Shape file vector data format flight was created using Geosoft and ArcMap. Process_Date: 2019 Process_Step: Process_Description: Linedata Reformat - Original linedata ASCII format file reformatted to CSV file using UltraEdit. Geosoft database created by importing the new CSV file. Projection information was assigned to the Geosoft database. The database was split into flight lines, using the "Split a line based on a line channel" tool. Improved readme file. Process_Date: 2019 Process_Step: Process_Description: Data cataloged for archival and publication - All files were renamed and placed in a standardized set of folders according to the DGGS Geophysics Data Management Manual. Where applicable and as needed data were converted to newer file formats and new files were created. Supporting documentation including but not limited to readme text files, maps, figures, survey overview report, missing data type explanations, and metadata were created. Process_Date: 2019 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 4 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -159 Latitude_of_Projection_Origin: 0 False_Easting: 500000.000000 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: .00000001 Ordinate_Resolution: .00000001 Planar_Distance_Units: Meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1927 Ellipsoid_Name: Clarke 1866 Semi-major_Axis: 6378206.40000000037 Denominator_of_Flattening_Ratio: 294.978698199999997 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: ascii_data Entity_Type_Definition: ASCII format line data, other ASCII data Entity_Type_Definition_Source: GEONEX Aero Service and Sanders Geophysics Ltd. Entity_Attribute_Layer_Name: ascii_data Detailed_Description: Entity_Type: Entity_Type_Label: databases_geosoft Entity_Type_Definition: Geosoft format database of line data, other Geosoft format databases Entity_Type_Definition_Source: GEONEX Aero Service and Sanders Geophysics Ltd. Entity_Attribute_Layer_Name: databases_geosoft Detailed_Description: Entity_Type: Entity_Type_Label: documents Entity_Type_Definition: Project and field reports, survey background information, gridded data explanations, other supporting documentation Entity_Type_Definition_Source: GEONEX Aero Service and Sanders Geophysics Ltd. and Alaska Division of Geological & Geophysical Surveys (DGGS) Entity_Attribute_Layer_Name: documents Detailed_Description: Entity_Type: Entity_Type_Label: grids_ermapper Entity_Type_Definition: Geographically registered gridded data, ER Mapper ERS format Entity_Type_Definition_Source: GEONEX Aero Service and Sanders Geophysics Ltd. and Alaska Division of Geological & Geophysical Surveys (DGGS) Entity_Attribute_Layer_Name: grids_ermapper Detailed_Description: Entity_Type: Entity_Type_Label: grids_geosoft Entity_Type_Definition: Geosoft-format binary grids, these grids can be viewed in ESRI ArcMap using a free plugin from Geosoft or using the free viewer available from Geosoft Entity_Type_Definition_Source: GEONEX Aero Service and Sanders Geophysics Ltd. and Alaska Division of Geological & Geophysical Surveys (DGGS) Entity_Attribute_Layer_Name: grids_geosoft Detailed_Description: Entity_Type: Entity_Type_Label: images_registered Entity_Type_Definition: GeoTiff format images of all gridded data Entity_Type_Definition_Source: Alaska Division of Geological & Geophysical Surveys (DGGS) Entity_Attribute_Layer_Name: images_registered Detailed_Description: Entity_Type: Entity_Type_Label: kmz Entity_Type_Definition: Keyhole markup language (kml) kmz archive files of project data. Viewable in Google Earth and other compatible programs Entity_Type_Definition_Source: Alaska Division of Geological & Geophysical Surveys (DGGS) Entity_Attribute_Layer_Name: kmz Detailed_Description: Entity_Type: Entity_Type_Label: maps_pdf_format Entity_Type_Definition: Printable maps in pdf format Entity_Type_Definition_Source: GEONEX Aero Service and Sanders Geophysics Ltd. Entity_Attribute_Layer_Name: maps_pdf_format Detailed_Description: Entity_Type: Entity_Type_Label: vector_data Entity_Type_Definition: Line path, data contours, and survey boundary in ESRI shapefile (SHP) format, ESRI Geodatabase format, and/or AutoCAD dxf format Entity_Type_Definition_Source: GEONEX Aero Service and Sanders Geophysics Ltd. and Alaska Division of Geological & Geophysical Surveys (DGGS) Entity_Attribute_Layer_Name: vector_data Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Resource_Description: GPR 2020-12 Distribution_Liability: 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. Standard_Order_Process: Non-digital_Form: 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. Fees: Contact DGGS for current pricing Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: 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 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://doi.org/10.14509/30458 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20200610 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Person: Simone Montayne Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: Metadata Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Use_Constraints: 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. Metadata_Extensions: Online_Linkage: http://www.dggs.alaska.gov/metadata/dggs.ext Profile_Name: dggs metadata extensions