Geology of the Yakutat District, Gulf of Alaska Tertiary Province, Alaska

Miller, D.J.1961Geology of the Yakutat District, Gulf of Alaska Tertiary Province, AlaskageodatabaseOpen-File ReportOF 61-103United StatesU.S. Geological Survey1 sheet, scale 1:96,000https://dggs.alaska.gov/pubs/id/10670Geology of the Yakutat District, Gulf of Alaska Tertiary Province, Alaska, Open-File Report 61-103, presents a detailed summary of bedrock geology in the Yakutat district, one of five maps compiled at a common scale to describe the Gulf of Alaska Tertiary province. The province forms a 300-mile arcuate belt where Tertiary sedimentary rocks are exposed or inferred beneath Quaternary deposits. Geologic work in the region was carried out intermittently from 1944 to 1960 as part of petroleum investigations in southern Alaska. The volcanic unit (Mzv) consists mainly of altered greenstone derived from flows, breccias, tuffs, and volcanic graywacke, with local chert and argillite. Exposures are sparse from Bear Island to the Ustay River, and related intrusive and fragmental rocks near Akwe Lake and Russell Fiord are included based on stratigraphic relations. The unit is overlain unconformably by the Yakutat Group, which contains graywacke, black argillite, interbedded shale and sandstone, and locally thick conglomeratic beds. Metamorphism increases southeastward toward the Alsek River, where the rocks grade into schist and phyllite. Fossils collected in 1960 from basal Yakutat Group beds at Akwe Lake include Buchia and Inoceramus, indicating a Late Jurassic to Cretaceous age range. Tertiary sedimentary rocks do not crop out in the mapped area but were encountered beneath coastal Quaternary deposits in wells drilled in the Yakutat district. Early reports of oil seeps were not confirmed, but exploration beginning in 1956, including surface mapping, seismic and gravity surveys, and four deep test wells, demonstrated the presence of petroleum and subsurface Tertiary sedimentary rocks beneath the coastal plain. By the end of 1960, all lowland areas of the Yakutat district were under Federal oil and gas leases. 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/10670.The purpose of this report was to describe the bedrock geology of the Yakutat district and to summarize geologic features relevant to assessing petroleum potential in the Gulf of Alaska Tertiary province. It documented the volcanic unit and Yakutat group, their ages, lithologies, and metamorphic trends, and compiled results from mid-twentieth-century exploration that demonstrated the presence of subsurface Tertiary sedimentary rocks and petroleum beneath the coastal plain.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/10.14509/30584.1962ground conditionCompleteNone planned-139.990030-138.01861259.75489259.052840ISO 19115 Topic CategorygeoscientificInformationAlaska Division of Geological & Geophysical SurveysArgilliteBedrockBedrock Geologic MapBedrock GeologyBuchiaChertCoastalConglomerateDioriteDrillingEolianEolian DepositsEstuaryExplorationFluvialFossilsGasGeneralizedGeologyGlacialGlacial DepositsGravelGraywackeGreenstoneIgneousInoceramusIntrusiveLimeMarbleMarineMarine DepositsMarine SedimentationMetamorphicMetamorphismMetasedimentary RocksPetroleumPhylliteResourcesRocksSandSandstoneSchistSedimentSedimentaryShaleSlateSurfaceSurficialTillVolcanicVolcaniclasticAlaska Division of Geological & Geophysical SurveysAhrnklin RiverAka LakeAkwe LakeAkwe RiverAlsek LakeAlsek RiverAntlen RiverArrecifes PointBear IslandBeasley CreekBlacksand IslandBroken Oar CoveCannery CreekCanoe IslandCanoe PassCape StossChicago HarborClear CreekDangerous RiverDoame RiverDoggie IslandDolgoi IslandEleanor CoveEmile CreekFirst RapidsFitzgerald IslandGateway KnobGilbert SpitGines CreekGlacier Bay National PreserveGraveyard CoveGregson IslandHarlequin LakeHarlequinn LakeHatchet PassHatchet PointHumpback CoveHumpback CreekItalio LakeItalio RiverKardy LakeKhantaak BeachKhantaak IslandKnight IslandKooisk PointKriwoi IslandKrutoi IslandKunayosh CreekLake RedfieldLost RiverMartin GlacierMiller CreekMiller GlacierMoser CreekMount MallottMount TebenkofMountain LakeMuddy CreekNeeg IslandNew ReefsNortheast PointOcean CapeOcean Cape LightOld Situk CreekOld Situk RiverOnklat CreekOphir CreekOtmeloi IslandPhipps CapePhipps PeninsulaPoint CarrewPoint MunozPoint TurnerPort MulgravePuget CovePyramid PointRedfield CoveRocky LakeRodman GlacierRurik HarborRussell FiordSawmill CoveSeal CreekSeal RiverShack CreekShipyard CoveSitukSituk LakeSituk RiverSlate PeakSplit CreekSquare LakeSummit LakeSummit LakesTaaltsug RiverTanis LakeTanis RiverTawah CreekTla-Xagh IslandTlegan RiverTriangle LakeUstay LakeUstay RiverVankahini RiverWilliams CreekYakutatYakutat Mining DistrictAlaska Division of Geological & Geophysical SurveysYakutat GroupWalker, J.D., Geissman, J.W., Bowring, S.A, and Babcock, L.E., comp., 2012, Geologic Time Scale v. 4.0: Geological Society of AmericaCretaceousMesozoicQuaternaryThis report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below).Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product.Alaska Division of Geological & Geophysical SurveysMetadata Managermailing and physical

3354 College Road

FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysPlease 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.Geology was compiled mainly from field mapping and photo-interpretation by D. J. Miller in 1960. Bedrock geology in the area adjoining Yakutat Bay and Russell Fiord was taken from R. S. Tarr and B. S. Butler, U.S. Geological Survey Professional Paper 64, plate 37, 1909. Geology in the vicinity of Moser Creek and Miller Creek was based on field notes of Eliot Blackwelder from 1906. 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.Combellick, R.A.1994Geologic hazards in the Yakataga planning area, southeastern Alaska: an overviewReport of InvestigationRI 94-29Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys9 phttps://doi.org/10.14509/2512Combellick, R.A.Long, W.E.1983Geologic hazards in southeastern Alaska: an overviewReport of InvestigationRI 83-17Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys17 phttps://doi.org/10.14509/2356Kornbrath, R.W.1995Analysis of historical oil and gas lease sale and exploration data for AlaskaReport of InvestigationRI 95-11Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys22 phttps://doi.org/10.14509/2525Lyle, W.M.Palmer, I.F., Jr.1976Stratigraphic study of the Gulf of Alaska tertiary province, northern Gulf of Alaska areaAlaska Open-File ReportAOF 93Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys173 p., 23 sheetshttps://doi.org/10.14509/189McGee, D.L.1973Gulf of Alaska petroleum seepsAlaska Open-File ReportAOF 32Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys9 phttps://doi.org/10.14509/131Suleimani, E.N.Nicolsky, D.J.Koehler, R.D.2016Tsunami inundation maps for Yakutat, AlaskaReport of InvestigationRI 2016-2Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys47 p., 1 sheet, scale 1:10,000https://doi.org/10.14509/29577Suleimani, E.N.Nicolsky, D.J.Koehler, R.D.2018Potential maximum permanent flooding, Yakutat, AlaskaReport of InvestigationRI 2016-2AFairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys1 sheet, scale 1:10,000https://doi.org/10.14509/30109Attribute 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.All polygon features were topologically validated according to the AK GeMS geologic mapping schema specifications.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.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.Ekberg, P.G.Hendricks, M.D.Athey, J.E.2021AK GeMS symbology: A description of the AK GeMS style fileMiscellaneous PublicationMP 169Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys7 phttps://doi.org/10.14509/30584paper2021publication dateEkberg, P.G. and others, 2021GIS analysis and digital cartographyHendricks, M.D.Ekberg, P.G.Athey, J.E.Wyatt, W.C.Willingham, A.L.Naibert, T.J.2021AK GeMS data dictionary: A description of the Alaska geologic mapping schemaMiscellaneous PublicationMP 170Fairbanks, Alaska, United StatesAlaska Division of Geological & Geophysical Surveys10 phttps://doi.org/10.14509/30669paper2021publication dateHendricks, M.D. and others, 2021GIS analysis and digital cartographyU.S. Geological Survey National Cooperative Geologic Mapping Program2020GeMS (Geologic Map Schema) - A standard format for the digital publication of geologic mapsTechniques and MethodsTM 11-B10United StatesU.S. Geological Survey1 phttps://dggs.alaska.gov/pubs/id/30585paper2020publication dateU.S. Geological Survey National Cooperative Geologic Mapping Program, 2020GIS analysis and digital cartographyGeologic mapping - Bedrock geology was compiled from field mapping and photo-interpretation carried out by D. J. Miller in 1960, supplemented by earlier geologic mapping in the Yakutat Bay and Russell Fiord area by R. S. Tarr and B. S. Butler (USGS Prof. Paper 64, 1909) and by field notes recorded by Eliot Blackwelder in 1906 for the Moser Creek and Miller Creek area. Geologic interpretation incorporated descriptions of the volcanic unit and Yakutat group from published USGS studies, fossil identifications from 1960 field collections, and results from mid-twentieth-century petroleum exploration, including surface mapping, seismic and gravity surveys, and drilling of four deep test wells that confirmed the presence of subsurface Tertiary sedimentary rocks beneath the coastal plain.1962Data 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.2026vectorUniversal Transverse Mercator70.999600-1410500000.0000000coordinate pair.00000001.00000001MetersNAD27Clarke 18666378206.4294.9786982yakutat_ak_gems_dbGeodatabase, layer files, style files, and fontsDGGS and USGSyakutat_ak_gems_dbyakutat_gems_dbGeodatabase, layer files, style files, and fontsDGGS and USGSyakutat_gems_dbyakutat_gems_geopackageSQLite Database fileDGGS and USGSyakutat_gems_geopackageyakutat_gems_shapefileShapefiles and open data filesDGGS and USGSyakutat_gems_shapefileAlaska Division of Geological & Geophysical SurveysMetadata Managermailing and physical

3354 College Road

FairbanksAK99709-3707USA(907)451-5020(907)451-5050dggspubs@alaska.gov8 am to 4:30 pm, Monday through Friday, except State holidaysFGDC Content Standard for Digital Geospatial MetadataFGDC-STD-001-1998If 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.https://dggs.alaska.gov/metadata/dggs.extdggs metadata extensions