Identification_Information: Citation: Citation_Information: Originator: Twelker, Evan Publication_Date: 2026 Title: Geologic investigation of the Chena-Pogo area, interior Alaska Geospatial_Data_Presentation_Form: geodatabase Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2026-3 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 1 p. Online_Linkage: https://doi.org/10.14509/32111 Description: Abstract: Geologic investigation of the Chena-Pogo area, interior Alaska, Preliminary Interpretive Report 2026-3, updates the bedrock geologic mapping of a 14,530-sq-km (5,610-sq-mi) area in the Yukon-Tanana Upland (YTU) of eastern Interior Alaska. The goals of the project are to better understand the geologic framework of known mineralization, to support the exploration and discovery of new mineral resources in the area, and to build scientific understanding of the geology of the YTU, one of Alaska's most active and important mineral belts. The project area has been a focus of gold exploration for several decades but also has additional significance for its potential to host critical minerals such as antimony, bismuth, tellurium, and tungsten. Project work was completed by Alaska Division of Geological & Geophysical Surveys (DGGS) staff and collaborators during 2023, 2024, and 2025 field seasons and draws on additional published and unpublished work completed during prior years by DGGS, University of Alaska, and U.S. Geological Survey staff. 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 Alaska Division of Geological & Geophysical Surveys website: http://doi.org/10.14509/32111. Purpose: This geologic map provides updated bedrock geologic mapping of Alaska's Yukon-Tanana Upland to support mineral-resource evaluation, improve understanding of the region's geologic framework, and inform studies of both known mineralization and critical-mineral potential. The resulting geologic information supports responsible resource development, guides land-management decisions, and strengthens the State of Alaska's understanding of its mineral-resource base. 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: Range_of_Dates/Times: Beginning_Date: 2023 Ending_Date: 2026 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -147.521933 East_Bounding_Coordinate: -143.680082 North_Bounding_Coordinate: 65.415874 South_Bounding_Coordinate: 64.228578 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: Allochthon Theme_Keyword: Amphibolite Theme_Keyword: Andesite Theme_Keyword: Argillite Theme_Keyword: Basalt Theme_Keyword: Batholith Theme_Keyword: Bedrock Theme_Keyword: Carbonates Theme_Keyword: Conglomerate Theme_Keyword: Correlation Theme_Keyword: DGGS Theme_Keyword: Dike Theme_Keyword: Diorite Theme_Keyword: Dolomite Theme_Keyword: Dolostone Theme_Keyword: Dunite Theme_Keyword: Earth MRI Theme_Keyword: Exhumation Theme_Keyword: Exploration Theme_Keyword: Faults Theme_Keyword: Fossils Theme_Keyword: Gabbro Theme_Keyword: Garnet Theme_Keyword: GeMS DB L3 Compliant Theme_Keyword: GeMS DB v2 Theme_Keyword: Geodatabase Theme_Keyword: Geologic Theme_Keyword: Geologic Map Theme_Keyword: Geological Process Theme_Keyword: Geology Theme_Keyword: Gneiss Theme_Keyword: Granite Theme_Keyword: Granodiorite Theme_Keyword: Graphite Theme_Keyword: Graywacke Theme_Keyword: Greenschist Theme_Keyword: Greenstone Theme_Keyword: Hadrosaur Theme_Keyword: Hornfels Theme_Keyword: Igneous Theme_Keyword: Igneous Rocks Theme_Keyword: Interpretation Theme_Keyword: Intrusive Theme_Keyword: Jade Theme_Keyword: Lithology Theme_Keyword: Magnetic Data Theme_Keyword: Magnetic Susceptibility Theme_Keyword: Marble Theme_Keyword: Metagenesis Theme_Keyword: Metaigneous Units Theme_Keyword: Metals Theme_Keyword: Metamorphic Theme_Keyword: Metamorphic Deposits Theme_Keyword: Metamorphic Grade Theme_Keyword: Metamorphic Minerals Theme_Keyword: Metamorphic Rocks Theme_Keyword: Metamorphism Theme_Keyword: Metasedimentary Rocks Theme_Keyword: Metavolcanic rocks Theme_Keyword: Metavolcanics Theme_Keyword: Mineral Assessment Theme_Keyword: Mineral Deposits Theme_Keyword: Mineral Development Theme_Keyword: Mineral Exploration Theme_Keyword: Mineral Resources Theme_Keyword: Mineralogy Theme_Keyword: Minerals Theme_Keyword: Mining Theme_Keyword: Monazite Theme_Keyword: Monzodiorite Theme_Keyword: Monzogranite Theme_Keyword: Monzonite Theme_Keyword: Orthogneiss Theme_Keyword: Outcrop Theme_Keyword: Pegmatite Theme_Keyword: Petrogenesis Theme_Keyword: Petrographic Theme_Keyword: Petrography Theme_Keyword: Petrology Theme_Keyword: Phyllite Theme_Keyword: Plagioclase Theme_Keyword: Plutonic Theme_Keyword: Plutonic Complex Theme_Keyword: Plutonic Hosted Theme_Keyword: Plutonic Rocks Theme_Keyword: Plutons Theme_Keyword: Porphyry Theme_Keyword: Quartzite Theme_Keyword: Rare Earth Elements Theme_Keyword: Regional Theme_Keyword: Regional Metamorphism Theme_Keyword: Resource Assessment Theme_Keyword: Resource Evaluation Theme_Keyword: Resources Theme_Keyword: Rhyolite Theme_Keyword: Rock Properties Theme_Keyword: Rock Units Theme_Keyword: Rocks Theme_Keyword: Sandstone Theme_Keyword: Schist Theme_Keyword: Sediment Theme_Keyword: Sedimentary Theme_Keyword: Sedimentary Rocks Theme_Keyword: Serpentinite Theme_Keyword: Shale Theme_Keyword: Sillimanite Theme_Keyword: Skarn Theme_Keyword: Slate Theme_Keyword: Strategic and Critical Minerals Assessment Project Theme_Keyword: Strategic Minerals Theme_Keyword: Stratigraphy Theme_Keyword: Structural Geology Theme_Keyword: Talc Theme_Keyword: Tectonics Theme_Keyword: Terranes Theme_Keyword: Tonalite Theme_Keyword: Ultramafic Theme_Keyword: Ultramafic Rocks Theme_Keyword: Undifferentiated Bedrock Theme_Keyword: Volcanic Theme_Keyword: Volcanic Rocks Theme_Keyword: Volcaniclastic Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Acme Creek Place_Keyword: Alaska Place_Keyword: Anderson Creek Place_Keyword: Angel Creek Place_Keyword: Antimony Creek Place_Keyword: Anvil Creek Place_Keyword: Bathing Beauty Pond Place_Keyword: Bear Creek Place_Keyword: Bear Lake Place_Keyword: Beaver Creek Place_Keyword: Birch Creek Place_Keyword: Black Bear Creek Place_Keyword: Black Mountain Place_Keyword: Blackshell Creek Place_Keyword: Blair Lakes Place_Keyword: Bluestone Creek Place_Keyword: Bonanza Creek Place_Keyword: Bonnifield Mining District Place_Keyword: Boulder Creek Place_Keyword: Buckley Bar Creek Place_Keyword: Bullfrog Creek Place_Keyword: Butte Creek Place_Keyword: California Creek Place_Keyword: Camp Creek Place_Keyword: Caribou Creek Place_Keyword: Cash Creek Place_Keyword: Central Creek Place_Keyword: Chena Hot Springs Place_Keyword: Chena Lake Place_Keyword: Chena River Place_Keyword: Circle Mining District Place_Keyword: Clear Creek Place_Keyword: Clums Fork Birch Creek Place_Keyword: Colorado Creek Place_Keyword: Cottonwood Creek Place_Keyword: Crawford Creek Place_Keyword: Dan Creek Place_Keyword: Deep Creek Place_Keyword: Demar Creek Place_Keyword: Denver Creek Place_Keyword: Dexter Creek Place_Keyword: Divide Creek Place_Keyword: Dry Creek Place_Keyword: Eldorado Creek Place_Keyword: Emory Creek Place_Keyword: Fairbanks Mining District Place_Keyword: Far Mountain Place_Keyword: Flag Hill Place_Keyword: Flat Creek Place_Keyword: Flume Creek Place_Keyword: Fourmile Creek Place_Keyword: French Creek Place_Keyword: Glacier Creek Place_Keyword: Globe Creek Place_Keyword: Gold Creek Place_Keyword: Goodpaster Mining District Place_Keyword: Goodpaster River Place_Keyword: Goose Creek Place_Keyword: Granite Creek Place_Keyword: Granite Tors Place_Keyword: Grayling Lake Place_Keyword: Graystone Creek Place_Keyword: Great Unknown Creek Place_Keyword: Grizzly Bear Mine Place_Keyword: Grizzly Creek Place_Keyword: Gulch Creek Place_Keyword: Harding Lake Place_Keyword: Harrison Creek Place_Keyword: Hartman Lake Place_Keyword: Hidden Lake Place_Keyword: Horner Creek Place_Keyword: Horse Creek Place_Keyword: Horseshoe Lake Place_Keyword: Hunts Creek Place_Keyword: Indian Creek Place_Keyword: Johnson Creek Place_Keyword: Jones Pass Place_Keyword: King Creek Place_Keyword: Last Chance Creek Place_Keyword: Lawson Creek Place_Keyword: Lenant Creek Place_Keyword: Lohi Creek Place_Keyword: Lost Creek Place_Keyword: Lyrad Creek Place_Keyword: Maiden Creek Place_Keyword: Malburn Creek Place_Keyword: Manchu Lake Place_Keyword: Marshall Mountain Place_Keyword: Marten Creek Place_Keyword: Mascot Creek Place_Keyword: Mastadon Creek Place_Keyword: Montana Creek Place_Keyword: Monument Creek Place_Keyword: Moose Creek Place_Keyword: Moose Lake Place_Keyword: Mosquito Creek Place_Keyword: Munson Creek Place_Keyword: Ninetyeight Creek Place_Keyword: No Grub Creek Place_Keyword: North Pole Place_Keyword: Nugget Creek Place_Keyword: Ohio Creek Place_Keyword: Olympia Creek Place_Keyword: Ottertail Creek Place_Keyword: Paldo Creek Place_Keyword: Palmer Creek Place_Keyword: Pasco Creek Place_Keyword: Pine Creek Place_Keyword: Pleasant Creek Place_Keyword: Pleasant Valley Place_Keyword: Polaris Lake Place_Keyword: Porcupine Creek Place_Keyword: Portage Creek Place_Keyword: Quartz Creek Place_Keyword: Redmond Creek Place_Keyword: Richardson Mining District Place_Keyword: Ricks Creek Place_Keyword: Rock Creek Place_Keyword: Salcha River Place_Keyword: Salmonfoot Creek Place_Keyword: Serpentine Creek Place_Keyword: Sevenmile Creek Place_Keyword: Seventymile Place_Keyword: Shamrock Creek Place_Keyword: Shaw Creek Place_Keyword: Shawnee Peak Place_Keyword: Sheep Creek Place_Keyword: Slate Creek Place_Keyword: Sonora Creek Place_Keyword: Stiles Creek Place_Keyword: Stone Boy Creek Place_Keyword: Stone Boys Tent Creek Place_Keyword: Stringer Road Pond Place_Keyword: Stuart Creek Place_Keyword: Sullivan Creek Place_Keyword: Summit Creek Place_Keyword: Tanana River Place_Keyword: Teuchet Creek Place_Keyword: Thomas Creek Place_Keyword: Tibbs Creek Place_Keyword: Volcano Creek Place_Keyword: Wheeler Creek Place_Keyword: White Creek Place_Keyword: Wickersham Creek Place_Keyword: Williams Creek Place_Keyword: Willow Creek Place_Keyword: Wolf Creek Place_Keyword: Wolverine Creek Stratum: Stratum_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Stratum_Keyword: Fairbanks Schist Stratum_Keyword: Fairbanks-Chena Assemblage Stratum_Keyword: Lake George Assemblage Stratum_Keyword: Seventymile Terrane Stratum_Keyword: Yukon-Tanana Terrane Stratum_Keyword: Yukon-Tanana Upland Temporal: Temporal_Keyword_Thesaurus: Walker, J.D., Geissman, J.W., Bowring, S.A, and Babcock, L.E., comp., 2012, Geologic Time Scale v. 4.0: Geological Society of America Temporal_Keyword: Devonian Temporal_Keyword: Late Cretaceous Temporal_Keyword: Late Devonian Temporal_Keyword: Mississippian Temporal_Keyword: Paleocene Temporal_Keyword: Paleozoic Temporal_Keyword: Precambrian Temporal_Keyword: Proterozoic Temporal_Keyword: Triassic 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: We thank the many individuals and organizations who contributed to this project. Northern Star Resources Ltd. geologists shared valuable knowledge, maps, and samples from the Pogo Mine area, and Resolution Minerals Ltd., Millrock Resources Inc., and Christine Lawley provided prior mapping and geophysical models that aided interpretation. We appreciate insights from Peter Franz (Metallogeny Inc.) and cooperation from Tectonic Metals Inc. in the Tibbs and Paldo Creek areas. U.S. Geological Survey collaborators offered helpful discussions, and Jacob Murchek supplied a merged aeromagnetic grid used during fieldwork. The Arizona LaserChron Center, the University of Alaska Advanced Instrumentation Laboratory, and the University of Alaska Geochronology facility supported geochronologic and mineral-chemical analyses. We thank the U.S. Bureau of Land Management Eastern Interior Field Office and Alaska State Parks for assistance with permitting and access. Chena Hot Springs Resort provided an excellent field base, and we are especially grateful to Keith Warren and Aurora Aviation Services for safe and reliable air support. This project was funded by State of Alaska capital funds and the U.S. Geological Survey Earth MRI program (cooperative agreement G23AC00372). The views expressed are those of the authors and do not represent U.S. Geological Survey policy; trade names are used for descriptive purposes only and do not imply endorsement. Cross_Reference: Citation_Information: Originator: Emond, A.M. Originator: MPX Geophysics LTD Publication_Date: 2022 Title: Tanana River and Big Delta airborne magnetic and radiometric survey Series_Information: Series_Name: Geophysical Report Issue_Identification: GPR 2022-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 4 p Online_Linkage: https://doi.org/10.14509/30899 Cross_Reference: Citation_Information: Originator: Gavel, M.M. Originator: Regan, S.P. Originator: Holland, Mark Originator: Wildland, A.D. Originator: Wypych, Alicja Originator: Naibert, T.J. Originator: Twelker, Evan Publication_Date: 2023 Title: U-Pb zircon geochronology of bedrock samples collected in the Eagle and Tanacross quadrangles, eastern Alaska Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2023-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 38 p Online_Linkage: https://doi.org/10.14509/31013 Cross_Reference: Citation_Information: Originator: Gavel, M.M. Originator: Wypych, Alicja Originator: Naibert, T.J. Originator: Twelker, Evan Originator: Newberry, R.J. Originator: Barrera, M.L. Originator: Szumigala, D.J. Originator: Truskowski, C.M. Originator: Muller, I.P. Originator: Fessenden, S.N. Originator: Blackwell, N.J. Originator: Harvey, D.A. Originator: Wildland, A.D. Publication_Date: 2025 Title: Bedrock geologic map of the Mount Harper-Middle Fork area, Eagle Quadrangle, Alaska Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2025-2D Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 1 sheet, scale 1:100,000 Online_Linkage: https://doi.org/10.14509/31652 Cross_Reference: Citation_Information: Originator: Hendricks, M.D. Originator: Macpherson, A.E. Originator: Athey, J.E. Originator: Wyatt, W.C. Originator: Montayne, Simone Originator: Buchanan, J.W. Originator: Rivera, P.G. Originator: Steinleitner, A.M. Publication_Date: 2024 Title: AK GeMS data dictionary: A description of the Alaska geologic mapping schema Series_Information: Series_Name: Miscellaneous Publication Issue_Identification: MP 170 v. 2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 13 p Online_Linkage: https://doi.org/10.14509/31172 Cross_Reference: Citation_Information: Originator: Moshrefzadeh, Jamshid Originator: Acosta, M.D. Originator: Barrera, M.L. Originator: Buchanan, J.W. Originator: Naibert, T.J. Originator: Newberry, R.J. Originator: Norwood, L.P. Originator: Regan, S.P. Originator: Szumigala, D.J. Originator: Twelker, Evan Publication_Date: 2025 Title: Geochemical data from samples collected in 2024 for the Chena and Steese projects, Big Delta, Circle, Fairbanks, and Livengood quadrangles, Alaska Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2025-17 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 3 p Online_Linkage: https://doi.org/10.14509/31692 Cross_Reference: Citation_Information: Originator: Moshrefzadeh, J.A. Originator: Naibert, T.J. Originator: Hofmann, Florian Originator: Newberry, R.J. Originator: Twelker, Evan Originator: Buchanan, J.W. Publication_Date: 2026 Title: 40Ar/39Ar geochronology data from the Big Delta and Circle quadrangles, Alaska Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2026-14 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 55 p Online_Linkage: https://doi.org/10.14509/32086 Cross_Reference: Citation_Information: Originator: Naibert, T.J. Originator: Benowitz, J.A. Originator: Wypych, Alicja Originator: Sicard, K.R. Originator: Twelker, Evan Publication_Date: 2020 Title: 40Ar/39Ar data from the Tanacross D-1 and parts of the D-2, C-1, and C-2 quadrangles, Alaska Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2020-12 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 35 p Online_Linkage: https://doi.org/10.14509/30466 Cross_Reference: Citation_Information: Originator: Naibert, T.J. Originator: Wypych, Alicja Originator: Newberry, R.J. Originator: Twelker, Evan Originator: Gavel, M.M. Originator: Wildland, A.D. Originator: Barrera, M.L. Originator: Szumigala, D.J. Originator: Regan, S.P. Originator: Avirett, D.F. Originator: Bernard, C.M. Originator: Blackwell, N.J. Originator: Fessenden, S.N. Originator: Harvey, D.A. Originator: Hubbard, A.K. Originator: Masterman, S.S. Originator: Muller, I.P. Originator: Turner, M.M. Originator: Wyatt, W.C. Publication_Date: 2024 Title: Geologic background and map unit descriptions to accompany bedrock geologic maps of the western Tanacross and Taylor Mountain areas, Tanacross and Eagle quadrangles, Alaska Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2024-6A Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 39 p Online_Linkage: https://doi.org/10.14509/31167 Cross_Reference: Citation_Information: Originator: Newberry, R.J. Originator: Bundtzen, T.K. Originator: Clautice, K.H. Originator: Combellick, R.A. Originator: Douglas, Tom Originator: Laird, G.M. Originator: Liss, S.A. Originator: Pinney, D.S. Originator: Reifenstuhl, R.R. Originator: Solie, D.N. Publication_Date: 1996 Title: Preliminary geologic map of the Fairbanks mining district, Alaska Series_Information: Series_Name: Public Data File Issue_Identification: PDF 96-16 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 17 p., 2 sheets, scale 1:63,360 Online_Linkage: https://doi.org/10.14509/1740 Cross_Reference: Citation_Information: Originator: Newberry, R.J. Originator: Twelker, Evan Publication_Date: 2021 Title: Metamorphism of the Ladue River-Mount Fairplay area Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2021-5B Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: p. 33-39 Online_Linkage: https://doi.org/10.14509/30736 Cross_Reference: Citation_Information: Originator: Newberry, R.J. Originator: Moshrefzadeh, J.A. Publication_Date: 2026 Title: Interior Alaska amphibolite mineral compositions: A key to distinguishing metamorphic assemblage Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2026-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 33 p Online_Linkage: https://doi.org/10.14509/32081 Cross_Reference: Citation_Information: Originator: Smith, T.E. Originator: Pessel, G.H. Originator: Wiltse, M.A. Publication_Date: 1987 Title: Mineral assessment of the Lime Peak-Mt. Prindle area, Alaska Series_Information: Series_Name: Miscellaneous Publication Issue_Identification: MP 29 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 712 p., 13 sheets, scale 1:63,360 Online_Linkage: https://doi.org/10.14509/731 Cross_Reference: Citation_Information: Originator: Solie, D.N. Originator: Werdon, M.B. Originator: Freeman, L.K. Originator: Newberry, R.J. Originator: Szumigala, D.J. Originator: Speeter, G.G. Originator: Elliott, B.A. Publication_Date: 2019 Title: Bedrock-geologic map, Alaska Highway corridor, Tetlin Junction, Alaska to Canada border Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2019-3 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 16 p., 2 sheets, scale 1:63,360 Online_Linkage: https://doi.org/10.14509/30038 Cross_Reference: Citation_Information: Originator: Twelker, Evan Originator: Newberry, R.J. Originator: Naibert, T.J. Originator: Wypych, Alicja Originator: Gavel, M.M. Originator: Barrera, M.L. Originator: Szumigala, D.J. Originator: Truskowski, C.M. Originator: Muller, I.P. Originator: Fessenden, S.N. Originator: Blackwell, N.J. Originator: Harvey, D.A. Originator: Wildland, A.D. Publication_Date: 2025 Title: Bedrock geologic maps of the Mount Harper-Middle Fork area, Volkmar River-Healy River area, Goodpaster River-Shaw Creek area, and the Richardson Mining District, Alaska Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2025-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 38 p Online_Linkage: https://doi.org/10.14509/31648 Cross_Reference: Citation_Information: Originator: Twelker, Evan Originator: Newberry, R.J. Originator: Wypych, Alicja Originator: Naibert, T.J. Originator: Wildland, A.D. Originator: Sicard, K.R. Originator: Regan, S.P. Originator: Athey, J.E. Originator: Wyatt, W.C. Originator: Lopez, J.A. Publication_Date: 2021 Title: Bedrock geologic map of the Ladue River-Mount Fairplay area, Tanacross and Nabesna quadrangles, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2021-5A Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: p. 1-32, 1 sheet, scale 1:100,000 Online_Linkage: https://doi.org/10.14509/30735 Cross_Reference: Citation_Information: Originator: Werdon, M.B. Originator: Athey, J.E. Originator: Szumigala, D.J. Originator: Newberry, R.J. Originator: Grady, J.C. Originator: Munly, W.C. Publication_Date: 2001 Title: Major-oxide, minor-oxide, trace-element, and geochemical data from rocks collected in the Salcha River-Pogo area in 2000, Big Delta and northwestern Eagle quadrangles, Alaska Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2001-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 19 p., 1 sheet, scale 1:250,000 Online_Linkage: https://doi.org/10.14509/2661 Cross_Reference: Citation_Information: Originator: Werdon, M.B. Originator: Newberry, R.J. Originator: Athey, J.E. Originator: Szumigala, D.J. Publication_Date: 2004 Title: Bedrock geologic map of the Salcha River-Pogo area, Big Delta Quadrangle, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2004-1B Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 19 p., 1 sheet, scale 1:63,360 Online_Linkage: https://doi.org/10.14509/3209 Cross_Reference: Citation_Information: Originator: Werdon, M.B. Originator: Newberry, R.J. Originator: Athey, J.E. Originator: Szumigala, D.J. Originator: Freeman, L.K. Originator: Lessard, R.R. Originator: Hendry, K.R. Originator: Wiltse, M.A. Publication_Date: 2003 Title: Major-oxide, minor-oxide, trace-element, and geochemical data from rocks collected in the Big Delta Quadrangle, Alaska in 2002 Series_Information: Series_Name: Raw Data File Issue_Identification: RDF 2003-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 45 p Online_Linkage: https://doi.org/10.14509/2997 Cross_Reference: Citation_Information: Originator: Wiltse, M.A. Originator: Reger, R.D. Originator: Newberry, R.J. Originator: Pessel, G.H. Originator: Pinney, D.S. Originator: Robinson, M.S. Originator: Solie, D.N. Publication_Date: 1995 Title: Bedrock geologic map of the Circle mining district, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 95-2B 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/10.14509/2515 Cross_Reference: Citation_Information: Originator: Wypych, Alicja Originator: Hubbard, T.D. Originator: Naibert, T.J. Originator: Athey, J.E. Originator: Newberry, R.J. Originator: Sicard, K.R. Originator: Twelker, Evan Originator: Werdon, M.B. Originator: Willingham, A.L. Originator: Wyatt, W.C. Originator: Lockett, A.C. Publication_Date: 2021 Title: Northeast Tanacross geologic map and map units and descriptions Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2020-9B Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: p. 9-26, 1 sheet, scale 1:63,360 Online_Linkage: https://doi.org/10.14509/30539 Cross_Reference: Citation_Information: Originator: Wypych, Alicja Originator: Jones, J.V., III Originator: O'Sullivan, Paul Publication_Date: 2020 Title: U-Pb Zircon ages from bedrock samples collected in the Tanacross D-1, and parts of the D-2, C-1, and C-2 quadrangles, Alaska Series_Information: Series_Name: Preliminary Interpretive Report Issue_Identification: PIR 2020-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 19 p Online_Linkage: https://doi.org/10.14509/30465 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 DGGS Preliminary Interpretive Report (PIR). PIRs present emergent interpretations of geologic mapping or analytical investigation. These publications are reviewed for clarity and consistency and receive limited peer review. 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 - DGGS Mineral Resources Section staff conducted bedrock geologic mapping across the 14,530-sq-km Chena-Pogo project area during the 2023-2025 field seasons. During fieldwork, crews collected 4,800 bedrock observation stations, 429 geochemical samples, and 51 geochronology samples, and measured magnetic-susceptibility values to support map-unit characterization. In addition, previously published DGGS and USGS maps covering portions of the project area were compiled and modified by correlating original map units to those used in this publication, removing surficial deposits where present, simplifying geologic detail for display at 1:100,000 scale, and updating interpretations based on new field and analytical data. To organize the final mapping, the project was divided into four 1:100,000-scale map sheets (NW Chena, NE Chena, SW Chena, and SE Chena). Across these sheets, map units were standardized and described in the accompanying report. For GIS distribution, the four maps were combined into a single geologic map database formatted in both the Geologic Mapping Schema (GeMS) and the Alaska Geologic Mapping Schema (AK GeMS). Process_Date: 2026 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: 6 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -147 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: WGS84 Ellipsoid_Name: WGS 84 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: chena_pogo_ak_gems_db Entity_Type_Definition: Geodatabase, layer files, style files, and fonts Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: chena_pogo_ak_gems_db Detailed_Description: Entity_Type: Entity_Type_Label: chena_pogo_gems_db Entity_Type_Definition: Geodatabase, layer files, style files, and fonts Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: chena_pogo_gems_db Detailed_Description: Entity_Type: Entity_Type_Label: chena_pogo_gems_geopackage Entity_Type_Definition: SQLite Database file Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: chena_pogo_gems_geopackage Detailed_Description: Entity_Type: Entity_Type_Label: chena_pogo_gems_shapefile Entity_Type_Definition: Shapefiles and open data files Entity_Type_Definition_Source: DGGS Entity_Attribute_Layer_Name: chena_pogo_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: PIR 2026-3 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://doi.org/10.14509/32111 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20260527 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