Identification_Information: Citation: Citation_Information: Originator: Weber, F.R. Publication_Date: 1961 Title: Reconnaissance engineering geology for the selection of highway route from Talkeetna to McGrath, Alaska Geospatial_Data_Presentation_Form: geodatabase Series_Information: Series_Name: Open-File Report Issue_Identification: OF 61-169 Publication_Information: Publication_Place: United States Publisher: U.S. Geological Survey Other_Citation_Details: 2 sheets, scale 1:250,000 Online_Linkage: https://dggs.alaska.gov/pubs/id/10671 Description: Abstract: Reconnaissance engineering geology for the selection of highway route from Talkeetna to McGrath, Alaska, Open-File Report 61-169, evaluates a potential highway corridor between Talkeetna and McGrath to support planning for expansion of Alaska's highway system. Field checks were completed in 1959 and 1960, and aerial photographs were used to map bedrock and surficial deposits throughout the corridor. The study provides a general geologic basis for identifying possible road routes and focuses on conditions that may influence construction. The area includes parts of the lower Susitna River valley, a narrow band across the Alaska Range, and a broad region to the northwest. Two eastern access options were examined: a route west from Talkeetna along the Petersville Road toward Rainy Pass, and a route west from Flat Lake that parallels the historic Iditarod Trail along the Susitna, Yentna, and Skwentna Rivers. Bedrock interpretation draws on published geologic reports, and geologic information for the Farewell-McGrath area is based largely on the work of Arthur T. Fernald. Geologic units were delineated primarily from aerial photographs and transferred to topographic maps; boundaries are approximate. Surficial materials important for engineering evaluation include flood plain and terrace alluvium, alluvial fans and aprons, bog deposits, talus and localized mass-movement debris, active and inactive glacial outwash, outwash fans, alpine and end moraines, multiple varieties of ground moraine, silt and colluvium over bedrock, poorly and well consolidated sedimentary rocks, granitic intrusive rocks, and volcanic rocks. Glaciation strongly affected the Susitna drainage, where large glaciers once filled the valley and overtopped nearby hills and low mountains. Older drift is commonly mantled by windblown silt. In the Kuskokwim drainage, valley glaciers advanced roughly 20 miles from the mountain front, leaving arcuate end moraines and outwash fans. Eolian sand and silt are widespread north of the range. Permafrost is sporadic in the Susitna area but widespread on the Kuskokwim side, where it must be considered in road design. Seasonal frost action can be intense in poorly drained, fine-grained sediments throughout the corridor. The dataset provides geologic, structural, stratigraphic, and geochronologic information organized according to the GeMS and AK GeMS mapping schemas. The complete report, geodatabase, and ESRI fonts and style files are available from the DGGS website: https://dggs.alaska.gov/pubs/id/10671. Purpose: The purpose of this study was to supply early geologic and engineering information needed to evaluate possible highway routes between Talkeetna and McGrath. The work used aerial photograph interpretation and field checks completed in 1959 and 1960 to identify terrain conditions that could have affected road construction. The results supported the State of Alaska by helping assess long-range transportation options across remote terrain, improving planning for future access to communities, resource areas, and regional corridors. Supplemental_Information: This geodatabase is organized according to the AK GeMS mapping schema Hendricks, M.D., Macpherson, A.E., Athey, J.E., Wyatt, W.C., Montayne, Simone, Buchanan, Wes, Rivera, P.G., and Steinleitner, A.M., 2024, AK GeMS data dictionary: A description of the Alaska geologic mapping schema: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 170 v. 2, 13 p. https://doi.org/10.14509/31172. The distribution package includes ESRI fonts and style files, along with usage instructions. Further documentation of the symbology is provided by Ekberg, P.G., Hendricks, M.D., and Athey, J.E., 2021, AK GeMS symbology: A description of the AK GeMS style file: Alaska Division of Geological & Geophysical Surveys Miscellaneous Publication 169, 7 p. https://doi.org/10.14509/30584. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 1960 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -155.780385 East_Bounding_Coordinate: -149.845804 North_Bounding_Coordinate: 63.026715 South_Bounding_Coordinate: 61.429066 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: GeMS DB L3 Compliant Theme_Keyword: GeMS DB v2 Theme_Keyword: Aerial Theme_Keyword: Alluvial Theme_Keyword: Alluvium Theme_Keyword: Bedrock Theme_Keyword: Colluvium Theme_Keyword: Drift Theme_Keyword: Engineering Theme_Keyword: Engineering Geology Theme_Keyword: Eolian Theme_Keyword: Fan Theme_Keyword: Felsic Theme_Keyword: Flood Theme_Keyword: Geologic Theme_Keyword: Geology Theme_Keyword: Glacial Theme_Keyword: Glaciation Theme_Keyword: Glaciers Theme_Keyword: Ice Theme_Keyword: Igneous Theme_Keyword: Interpretation Theme_Keyword: Intrusive Theme_Keyword: Moraines Theme_Keyword: Mountain Theme_Keyword: Outwash Theme_Keyword: Peat Theme_Keyword: Permafrost Theme_Keyword: Permafrost and Periglacial Theme_Keyword: Resources Theme_Keyword: Rocks Theme_Keyword: Sand Theme_Keyword: Sediment Theme_Keyword: Sedimentary Theme_Keyword: Silt Theme_Keyword: Slope Instability Theme_Keyword: Surficial Theme_Keyword: Talus Theme_Keyword: Terrace Theme_Keyword: Till Theme_Keyword: Volcanic Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Alaska Place_Keyword: Alexander Creek Place_Keyword: Alpine Place_Keyword: Bear Creek Place_Keyword: Beaver Creek Place_Keyword: Birch Creek Place_Keyword: Blackwater Creek Place_Keyword: Bonanza Creek Place_Keyword: Boulder Creek Place_Keyword: Candle Creek Place_Keyword: Canyon Creek Place_Keyword: Chickak River Place_Keyword: Chulitna River Place_Keyword: Clear Creek Place_Keyword: Coal Creek Place_Keyword: Dalzell Creek Place_Keyword: Deep Creek Place_Keyword: Deepbank Creek Place_Keyword: Dillinger River Place_Keyword: Divide Creek Place_Keyword: Dome Creek Place_Keyword: Eightmile Creek Place_Keyword: Fish Creek Place_Keyword: Glacier Creek Place_Keyword: Gold Creek Place_Keyword: Happy River Place_Keyword: Hayes River Place_Keyword: Kahiltna River Place_Keyword: Kichatna River Place_Keyword: Kuskokwim River Place_Keyword: McGrath Place_Keyword: Nakochna River Place_Keyword: Petersville Place_Keyword: Redoubt Mining District Place_Keyword: Salmon River Place_Keyword: Skwentna Place_Keyword: Sunshine Place_Keyword: Susitna Place_Keyword: Susitna River Place_Keyword: Takotna River Place_Keyword: Talachulitna River Place_Keyword: Talkeetna Place_Keyword: Talkeetna Lakes Place_Keyword: Talkeetna River Place_Keyword: Tatalina River Place_Keyword: Tatina River Place_Keyword: Tokositna River Place_Keyword: Tonzona River Place_Keyword: Trapper Creek Place_Keyword: Valdez Creek Mining District Place_Keyword: Yentna Mining District Place_Keyword: Yentna River 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 Contact_Instructions: Please view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. Data_Set_Credit: This map was converted to GeMS or digitized into GeMS by Kinney Engineering, LCC., quality controlled, and then finalized by DGGS staff (Chris Wyatt). Ally M. Steinleitner implemented final database quality control and packaging. This geologic map (or report or conversion or product, etc.) was funded by the USGS National Cooperative Geologic Mapping Program under STATEMAP award number G24AC00521, 2024, and the State of Alaska General Fund. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government. Cross_Reference: Citation_Information: Originator: Bundtzen, T.K. Originator: Laird, G.M. Publication_Date: 1980 Title: Preliminary geology of the McGrath - upper Innoko River area, western interior Alaska Series_Information: Series_Name: Alaska Open-File Report Issue_Identification: AOF 134 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 39 p., 2 sheets Online_Linkage: https://doi.org/10.14509/53 Cross_Reference: Citation_Information: Originator: Bundtzen, T.K. Originator: Laird, G.M. Publication_Date: 1983 Title: Geologic map of the McGrath D-6 Quadrangle, Alaska Series_Information: Series_Name: Professional Report Issue_Identification: PR 79 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 1 sheet, scale 1:63,360 Online_Linkage: https://doi.org/10.14509/2253 Cross_Reference: Citation_Information: Originator: Bundtzen, T.K. Originator: Harris, E.E. Originator: Gilbert, W.G. Publication_Date: 1997 Title: Geologic map of the eastern half of the McGrath Quadrangle, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 97-14A Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 34 p., 1 sheet, scale 1:125,000 Online_Linkage: https://doi.org/10.14509/2549 Cross_Reference: Citation_Information: Originator: Kline, J.T. Originator: Pinney, D.S. Publication_Date: 1997 Title: Derivative map of the geologic materials and hazards in the eastern half McGrath Quadrangle, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 97-14B Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 1 sheet, scale 1:125,000 Online_Linkage: https://doi.org/10.14509/2550 Cross_Reference: Citation_Information: Originator: Walser, S.L. Originator: Gillis, R.J. Originator: Bernt, J.D. Originator: Salisbury, J.B. Originator: Diaz, A.V. Originator: Hubbard, T.D. Publication_Date: 2026 Title: Geologic map of the West Susitna area, parts of the Tyonek C-3, C-4, D-4, and D-5 quadrangles, Alaska Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2026-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 10 p., 2 sheets, scale 1:50,000 Online_Linkage: https://doi.org/10.14509/32075 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Attribute fields within each feature class are populated using the map symbology and corresponding applicable values from the GeMS and AK GeMS specifications. When known, certainty in attribute interpretation is indicated in the relevant fields. Attribute accuracy varies throughout the map and is scale-dependent. Logical_Consistency_Report: All polygon features were topologically validated according to the AK GeMS geologic mapping schema specifications. Completeness_Report: This publication is a U.S. Geological Survey Open-File Report (OF), which provide rapid public release of scientific information. The series includes interpretive reports, maps, supporting data, preliminary findings, interim computer programs, user guides, and bibliographies. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Certainty in feature boundaries or location varies throughout the map. Data fields within each feature class and the accompanying orientation and location confidence lookup tables record the authors' degree of confidence in the location of applicable features. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Ekberg, P.G. Originator: Hendricks, M.D. Originator: Athey, J.E. Publication_Date: 2021 Title: AK GeMS symbology: A description of the AK GeMS style file Series_Information: Series_Name: Miscellaneous Publication Issue_Identification: MP 169 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 7 p Online_Linkage: https://doi.org/10.14509/30584 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2021 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Ekberg, P.G. and others, 2021 Source_Contribution: GIS analysis and digital cartography Source_Information: Source_Citation: Citation_Information: Originator: Hendricks, M.D. Originator: Ekberg, P.G. Originator: Athey, J.E. Originator: Wyatt, W.C. Originator: Willingham, A.L. Originator: Naibert, T.J. Publication_Date: 2021 Title: AK GeMS data dictionary: A description of the Alaska geologic mapping schema Series_Information: Series_Name: Miscellaneous Publication Issue_Identification: MP 170 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 10 p Online_Linkage: https://doi.org/10.14509/30669 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2021 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: Hendricks, M.D. and others, 2021 Source_Contribution: GIS analysis and digital cartography Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey National Cooperative Geologic Mapping Program Publication_Date: 2020 Title: GeMS (Geologic Map Schema) - A standard format for the digital publication of geologic maps Series_Information: Series_Name: Techniques and Methods Issue_Identification: TM 11-B10 Publication_Information: Publication_Place: United States Publisher: U.S. Geological Survey Other_Citation_Details: 1 p Online_Linkage: https://dggs.alaska.gov/pubs/id/30585 Type_of_Source_Media: paper Source_Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 2020 Source_Currentness_Reference: publication date Source_Citation_Abbreviation: U.S. Geological Survey National Cooperative Geologic Mapping Program, 2020 Source_Contribution: GIS analysis and digital cartography Process_Step: Process_Description: Geologic mapping - Aerial photographs were examined to identify bedrock, surficial deposits, glacial features, and terrain conditions relevant to highway route evaluation. Photo interpretation was supported by field checks completed in 1959 and 1960. Geologic units were delineated on the photographs, transferred to topographic maps, and classified according to engineering significance. Surficial materials were grouped into alluvial, bog, colluvial, mass-movement, glacial, eolian, and bedrock units to support assessment of construction conditions. Boundaries were considered approximate due to the reconnaissance nature of the work. Process_Date: 1960 Process_Step: Process_Description: Data packaging - DGGS organized and attributed the geologic and geographic features according to the AK GeMS schema, then programmatically transformed the data into four distribution formats: (1) an AK GeMS data package containing the full database and supporting files, (2) a GeMS data package converted to the USGS base standard, (3) a SQLite database file, and (4) a simplified shapefile package with shapefile representations of the data. Process_Date: 2026 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: vector Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 5 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -153 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: NAD27 Ellipsoid_Name: Clarke 1866 Semi-major_Axis: 6378206.4 Denominator_of_Flattening_Ratio: 294.9786982 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: talkeetna_to_mcgrath_ak_gems_db Entity_Type_Definition: Geodatabase, layer files, style files, and fonts Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: talkeetna_to_mcgrath_ak_gems_db Detailed_Description: Entity_Type: Entity_Type_Label: talkeetna_to_mcgrath_gems_db Entity_Type_Definition: Geodatabase, layer files, style files, and fonts Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: talkeetna_to_mcgrath_gems_db Detailed_Description: Entity_Type: Entity_Type_Label: talkeetna_to_mcgrath_gems_geopackage Entity_Type_Definition: SQLite Database file Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: talkeetna_to_mcgrath_gems_geopackage Detailed_Description: Entity_Type: Entity_Type_Label: talkeetna_to_mcgrath_gems_shapefile Entity_Type_Definition: Shapefiles and open data files Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: talkeetna_to_mcgrath_gems_shapefile 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 Contact_Instructions: Please view our website (https://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. Resource_Description: OF 61-169 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: geodatabase Format_Information_Content: geologic map Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://dggs.alaska.gov/pubs/id/10671 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20260901 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Person: Simone Montayne 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: https://dggs.alaska.gov/metadata/dggs.ext Profile_Name: dggs metadata extensions