Identification_Information: Citation: Citation_Information: Originator: Hopkins, D.M. Publication_Date: 1963 Title: Geology of the Imuruk Lake area, Seward Peninsula, Alaska Geospatial_Data_Presentation_Form: geodatabase Series_Information: Series_Name: Bulletin Issue_Identification: B 1141-C Publication_Information: Publication_Place: United States Publisher: U.S. Geological Survey Other_Citation_Details: p. C1-C101, 2 sheets Online_Linkage: https://dggs.alaska.gov/pubs/id/3628 Description: Abstract: Geology of the Imuruk Lake area, Seward Peninsula, Alaska, Bulletin 1141-C, presents a summary of the stratigraphy, glacial deposits, volcanic units, and late Cenozoic geologic history of the Imuruk Lake area on the Seward Peninsula. The sedimentary section includes a basal gravel more than 180 feet thick, a thin middle peaty lignite unit, and an upper gravel unit 3 to 90 feet thick. The middle unit contains mixed conifer and deciduous pollen similar to late Miocene and early Pliocene floras in Yakutia and the northern Alaska Range. The upper unit contains poplar and spruce or larch wood and may be early Pleistocene in age. Pleistocene deposits include glacial till and outwash of the Nome River (Illinoian) and Salmon Lake (Wisconsin) glaciations, windblown silt, stratified silt and peat, alluvial gravel, and lake sediments. Windblown silt mantles older bedrock, Kougarok gravel, and lava flows. Lake basins preserve three shoreline systems; the two older systems are warped, and the youngest is nearly horizontal. Drainage shifted from the Noxapaga River to the Kagruk River near the end of the Wisconsin glaciation. Late Cenozoic volcanic rocks cover much of the area. Five volcanic formations are distinguished by weathering profiles, frost brecciation, and silt cover: the Kagruk, Imaruk, Gosling, Camille, and Lost Jim units. Most lavas range from basalt to andesite, and a northwest trending belt produced inclusion bearing flows from shallow magma chambers. Volcanism likely occurred at intervals of several thousand years throughout late Cenozoic time. Late Cenozoic tectonic activity is recorded by warped surfaces, tilted lake basins, and fault scarps. Permafrost is widespread but thin where measured; permeable units contain thawed zones that store ground water in limestone, Kougarok gravel, lava flows, and flood plain gravel. Mineral resources include auriferous stream gravel, limonite, and diatomite. 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/3628. Purpose: The purpose of this report is to document the stratigraphy, glacial deposits, volcanic units, geomorphic features, and late Cenozoic geologic history of the Imuruk Lake area on the Seward Peninsula. The information supports geologic mapping, interpretation of past environmental conditions, evaluation of permafrost and ground-water resources, and identification of local mineral resources. It provides a framework for understanding the development of sedimentary, volcanic, and glacial features and for guiding future geologic and land-use studies in the region. 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: 1963 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -164.318714 East_Bounding_Coordinate: -162.736082 North_Bounding_Coordinate: 65.895306 South_Bounding_Coordinate: 65.310134 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: Alluvial Theme_Keyword: Alluvium Theme_Keyword: Amphibolite Theme_Keyword: Andesite Theme_Keyword: Aplite Theme_Keyword: Basalt Theme_Keyword: Basins Theme_Keyword: Bedrock Theme_Keyword: Bedrock Geologic Map Theme_Keyword: Bedrock Geology Theme_Keyword: Biotite Theme_Keyword: Contact Theme_Keyword: Correlation Theme_Keyword: Diorite Theme_Keyword: Drift Theme_Keyword: Faults Theme_Keyword: Felsic Theme_Keyword: Folding Theme_Keyword: Folds Theme_Keyword: Geologic Theme_Keyword: Geology Theme_Keyword: Glacial Theme_Keyword: Glacial Till Theme_Keyword: Glaciation Theme_Keyword: Gneiss Theme_Keyword: Granite Theme_Keyword: Gravel Theme_Keyword: Hornblende Theme_Keyword: Igneous Theme_Keyword: Intrusive Theme_Keyword: Lacustrine Theme_Keyword: Lacustrine Deposits Theme_Keyword: Lignite Theme_Keyword: Lithology Theme_Keyword: Metals Theme_Keyword: Monzonite Theme_Keyword: Non-Metals Theme_Keyword: Outwash Theme_Keyword: Outwash Deposits Theme_Keyword: Peat Theme_Keyword: Pegmatite Theme_Keyword: Quartz Theme_Keyword: Rocks Theme_Keyword: Sand Theme_Keyword: Schist Theme_Keyword: Sediment Theme_Keyword: Sedimentary Theme_Keyword: Silt Theme_Keyword: Surficial Theme_Keyword: Terrace Theme_Keyword: Till Theme_Keyword: Volcanic Theme_Keyword: Volcanic Deposits Theme_Keyword: Volcanic Rocks Theme_Keyword: Volcaniclastic Theme_Keyword: Volcaniclastic Deposits Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Agnes Lake Place_Keyword: American Creek Place_Keyword: Andesite Creek Place_Keyword: Andromeda Cone Place_Keyword: Arizona Creek Place_Keyword: Berry Creek Place_Keyword: Bilge Creek Place_Keyword: Black Butte Place_Keyword: Black Creek Place_Keyword: Blueberry Dome Place_Keyword: Burnt River Place_Keyword: Buzzard Creek Place_Keyword: Camille Cone Place_Keyword: Carex Creek Place_Keyword: Cassiope Cone Place_Keyword: Caviar Creek Place_Keyword: Collins Creek Place_Keyword: Cottonwood Creek Place_Keyword: Council Mining District Place_Keyword: Crossfox Butte Place_Keyword: Cygnus Cone Place_Keyword: Deep Creek Place_Keyword: Divide Creek Place_Keyword: Dryas Cone Place_Keyword: Erich Lake Place_Keyword: Esperanza Creek Place_Keyword: Eureka Creek Place_Keyword: Goose Creek Place_Keyword: Gosling Cone Place_Keyword: Granite Bay Place_Keyword: Grouse Creek Place_Keyword: Grus Cone Place_Keyword: Gull Islands Place_Keyword: Hannum Creek Place_Keyword: Hoodoo Hill Place_Keyword: Humboldt Creek Place_Keyword: Imuruk Lake Place_Keyword: Inmachuck River Place_Keyword: Joan Lake Place_Keyword: June Creek Place_Keyword: Kettle Dome Place_Keyword: Kougarok Mining District Place_Keyword: Koyuk River Place_Keyword: Kugruk River Place_Keyword: Kuzitrin Lake Place_Keyword: Kuzitrin River Place_Keyword: Largo Creek Place_Keyword: Largo Ridge Place_Keyword: Lava Lake Place_Keyword: Lost Jim Cone Place_Keyword: Magnet Creek Place_Keyword: Minnie Creek Place_Keyword: Mount Boyan Place_Keyword: Muskellunge Creek Place_Keyword: Nelson Creek Place_Keyword: Nimrod Hill Place_Keyword: Noxapaga Place_Keyword: Noxapaga River Place_Keyword: Noyes Creek Place_Keyword: Old Glory Creek Place_Keyword: Olivine Creek Place_Keyword: Perry Creek Place_Keyword: Pilgrim River Place_Keyword: Pinnell River Place_Keyword: Record City Place_Keyword: Rhododendron Cone Place_Keyword: Salix Bay Place_Keyword: Sandy Lake Place_Keyword: Skeleton Butte Place_Keyword: Skookum Creek Place_Keyword: Sturgeon Ridge Place_Keyword: Trail Creek Place_Keyword: Turner Creek Place_Keyword: Twin Calderas Place_Keyword: Virginia Butte Place_Keyword: Winona Creek Stratum: Stratum_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Stratum_Keyword: Camille Basalt Stratum_Keyword: Gosling Volcanics Stratum_Keyword: Kugururok Formation Stratum_Keyword: Lost Jim Basalt Stratum_Keyword: Nome River Glaciation Stratum_Keyword: Salmon Lake Glaciation 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: Cretaceous Temporal_Keyword: Jurassic Temporal_Keyword: Paleozoic Temporal_Keyword: Quaternary 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: Report and map credits include field assistance from A. T. Fernald, E. H. Muller, J. F. Seitz, R. S. Signfoos, W. B. Quay, and J. G. Sieh; logistical support from John Cross, D. H. Stewart, Charles Garnett, and John and Frank Whaley; radio support from CAA station KYTYK; technical review by M. P. Billings, R. F. Black, Kirk Bryan, R. E. Detterman, Maxim Guggisberg, T. W. V. Karlstrom, P. L. Killeen, Clyde Wahrhaftig, and J. R. Williams; and petrographic work by Joan P. Hopkins. 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: Herreid, G.H. Publication_Date: 1966 Title: Geology and geochemistry of the Inmachuk River map area, Seward Peninsula, Alaska Series_Information: Series_Name: Geologic Report Issue_Identification: GR 23 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Mines and Minerals Other_Citation_Details: 27 p., 1 sheet, scale 1:63,360 Online_Linkage: https://doi.org/10.14509/352 Cross_Reference: Citation_Information: Originator: Manning, K.H. Originator: Stevens, D.L. Publication_Date: 1982 Title: The Chicago Creek and Norton Sound area coal exploration programs - 1982 Series_Information: Series_Name: Public Data File Issue_Identification: PDF 83-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 103 p., 9 sheets Online_Linkage: https://doi.org/10.14509/1032 Cross_Reference: Citation_Information: Originator: Retherford, R.M. Originator: Hinderman, T.K. Originator: Hawley, C.C. Publication_Date: 1986 Title: Preliminary feasibility study of a coal mine at Chicago Creek, Seward Peninsula, Alaska: summary report Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 86-13 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/10.14509/2412 Cross_Reference: Citation_Information: Originator: Robinson, M.S. Originator: Stevens, D.L. Publication_Date: 1984 Title: Geologic map of the Seward Peninsula Series_Information: Series_Name: Special Report Issue_Identification: SR 34 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 1 sheet, scale 1:500,000 Online_Linkage: https://doi.org/10.14509/2633 Cross_Reference: Citation_Information: Originator: Shallit, A.B. Publication_Date: 1941 Title: The placer deposits in the upper Kougarok, Seward Peninsula, Alaska Series_Information: Series_Name: Miscellaneous Report Issue_Identification: MR 44-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Territorial Department of Mines Other_Citation_Details: 54 p., 7 sheets Online_Linkage: https://doi.org/10.14509/768 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 Bulletin (B), which present significant scientific data and interpretations of lasting value. Each Bulletin is considered complete for the scientific information it contains, and no additional chapters or companion volumes are required to understand the material presented. 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 - The author conducted geologic mapping and field investigations across the Imuruk Lake area to document sedimentary, glacial, volcanic, and geomorphic features. Field crews measured gravel, silt, peat, and lava units; identified shoreline features; and documented permafrost, ground-water conditions, and mineral occurrences. Staff collected pollen, wood, and rock samples for laboratory analysis and completed petrographic descriptions of volcanic and sedimentary materials. Logistical support, transportation, and radio communication enabled access to field sites and coordination during both field seasons. Technical review and laboratory analysis refined geologic interpretations and supported development of the final dataset. Process_Date: 1963 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: 3 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -165 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: imuruk_lake_ak_gems_db Entity_Type_Definition: Geodatabase, layer files, style files, and fonts Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: imuruk_lake_ak_gems_db Detailed_Description: Entity_Type: Entity_Type_Label: imuruk_lake_gems_db Entity_Type_Definition: Geodatabase, layer files, style files, and fonts Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: imuruk_lake_gems_db Detailed_Description: Entity_Type: Entity_Type_Label: imuruk_lake_gems_geopackage Entity_Type_Definition: SQLite Database file Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: imuruk_lake_gems_geopackage Detailed_Description: Entity_Type: Entity_Type_Label: imuruk_lake_gems_shapefile Entity_Type_Definition: Shapefiles and open data files Entity_Type_Definition_Source: DGGS and USGS Entity_Attribute_Layer_Name: imuruk_lake_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: B 1141-C 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/3628 Fees: Free download Metadata_Reference_Information: Metadata_Date: 20260730 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