Reger, R.D. Hubbard, T.D. Carver, G.C. 201111 document, map sheets and vector digital data Preliminary Interpretive Report PIR 2009-6A Fairbanks, Alaska - USA State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys 4 sheets. 1:63,360 scale http://www.dggs.alaska.gov/pubs/id/19741 During 2008-2010, the Alaska Division of Geological & Geophysical Surveys continued a program, begun in 2006, of reconnaissance mapping of surficial geology in the proposed natural-gas pipeline corridor through the upper Tanana River valley, a 12-mi-wide (19.3-km-wide) area that straddles the Alaska Highway through the upper Tanana River valley from the western boundaries of the Tanacross B-6 and C-6 Quadrangles near the mouth of the Robertson River eastward to the eastern boundaries of the Tanacross A-4 and B-4 Quadrangles near Tetlin Junction. Mapping during 2008-2010 in the Tanacross Quadrangle linked with mapping of surficial geology completed in the Big Delta and Mt. Hayes quadrangles in 2006-2007. Surficial geology was initially mapped in this second corridor segment by interpreting ~1:65,000-scale, false-color, infrared aerial photographs taken in July 1978, August 1980, and July 1983.Verification of photo mapping was accomplished during the 2008-2010 summer field season, when map units were described, soil pits were hand dug, and samples were collected for analyses. The Alaska Division of Geological & Geophysical Surveys conducted this project, funded by the state legislature, to evaluate the geology, geohazard and material resources along the Alaska Highway corridor from Delta Junction to the Canada border. This was in preparation for a proposed natural gas pipeline, so that a baseline of geologic data would be publicly available upon which preliminary decisions could be made. The work was designed to serve as the springboard for the detailed work which would be required if a pipeline were to be built along this corridor. The DGGS metadata standard extends the FGDC standard to also include elements that are required to facilitate our internal data management. These elements, referred to as 'layers', group and describe files that have intrinsic logical or topological relationships. Each layer is listed and described in detail under its own heading starting 'Entity_Type_Label'. Layers include: >surf_geology polygons of surficial-geologic map units >fault_features trace of known active faults discussed in Carver and others, 2010 >border outline shape of the study area >localities location of soil pits, radiocarbon samples, map localities and ventifact locality discussed in the text 197807 198008 198307 ground condition In work Unknown -144.0 -142.50000 63.741146 63.166099 ISO 19115 Topic Category geoscientificInformation Alaska Division of Geological & Geophysical Surveys Dunes Eolian Geologic Hazards Geologic Map Geologic Materials Geological Process Geology Geomorphology Glacial Deposits Moraines Glacier Outburst Flood Proposed Natural Gas Pipeline Remote Sensing Surficial Geology Surficial Transportation Corridor Unconsolidated Deposits Alaska Division of Geological & Geophysical Surveys Alaska Highway Corridor Alaska Range Alaska, State of Dot Lake Robertson River Tanacross Tanacross Quadrangle Taylor Highway Tok Tok River Alaska Division of Geological & Geophysical Surveys Delta Glaciation Donnelly Glaciation Alaska Division of Geological & Geophysical Surveys Pleistocene Quaternary Holocene 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). 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. 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. State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys GIS Data Manager/Cartographer mailing and physical

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Fairbanks AK 99709-3707 (907) 451-5029 (907) 451-5020 (907) 451-5050 dggspubs@alaska.gov You may view our web site at http://www.dggs.alaska.gov for the latest information on available data.Please e-mail your questions and data requests when possible since our web site and e-mail address will remain current even if our phone number and mailing address change. This research was supported by Alaska State Capital Improvement Projects funding. The authors gratefully acknowledge the helpful review by De Anne Stevens and Diana Solie as well as able cartographic assistance by Patricia Gallagher, Rachel Westbrook, James Weakland, and Gail Davidson. Much of the work was carried out under the direction of Diana Solie and her leadership was greatly appreciated. Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 3; ESRI ArcCatalog 10; ESRI ArcGIS 10 Reger, R.D. Hubbard, T.D. 2010 document,map sheets and vector digital data Preliminary Interpretive Report PIR 2009-6C Fairbanks, AK, USA State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys 4 sheets, 1:63,360 scale. http://www.dggs.alaska.gov/pubs/id/14447 Hubbard, T.D. Reger, R.D. 2010 map sheets, table and vector digital data Preliminary Interpretive Report PIR 2009-6B Fairbanks, Alaska - USA State of Alaska, Department of Natural Resources, 4 sheets 1:63,360 scale http://www.dggs.alaska.gov/pubs/id/19742 Reger, R.D. Stevens, D.S.P. Solie, D.N. 2008 documents, map sheets and vector digital data Preliminary Interpretive Report PIR 2008-3A Fairbanks, AK, USA Alaska Division of Geological & Geophysical Surveys 2 sheets, scale 1:63,360 Reger, R.D. Solie, D.N. 2008 document map sheets and vector digital data Preliminary Interpretive Report PIR 2008-3B Fairbanks, AK, USA Alaska Division of Geological & Geophysical Surveys 2 sheets, scale 1:63,360 Reger, R.D. Solie, D.N. 2008 document, map sheets and vector digital data Preliminary Interpretive Report PIR 2008-3C Fairbanks, AK, USA State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys 10 p., 2 sheets, scale 1:63,360 http://www.dggs.alaska.gov/pubs/id/17621 Carver, G.A. Bemis, S.P. Solie, D.N. Castonguay, S. Obermiller, K.E. 2010 document Preliminary Interpretive Report PIR 2010-1 Fairbanks , Alaska Alaska Division of Geological & Geophysical Surveys Carver, G.A. Bemis, S.P. Solie, D.N. Obermiller, K.E. 200812 document preliminary interpretive report PIR 2008-D Fairbanks, AK Alaska Division of Geological & Geophysical Surveys 32 p. Reger, R.D. Hubbard, T.D. 200910 abstract Geological Society of America Abstracts with Programs V. 41, No. 7 Boulder, CO Geological Society of America p. 637 Hubbard, T.D. Reger, R.D. 201010 Abstract Geological Society of America Abstracts with Programs vol. 42, No. 5 Boulder, CO Geological Society of America 703 p. Abstract on p. 310 Soil colors were described using the Munsell soil color charts. The Wentworth scale was used for grain size classification. Soil horizon descriptions in the map area used the U.S. Soil Conservation Service soil taxonomy (Soil Survey Staff, 1975). Sediment samples were collected for sieve analysis and radiocarbon age dating. Analytical data described above were utilized in developing the geologic interpretations presented in this report. The accuracy of the map unit boundary locations vary due to the scale and interpretive nature of the mapping but are expected to be accurate to at least 50 ft. Map units labeled with a "?" are considered to have an uncertain assignation. Information from previous geologic reports was incorporated during the interpretation process. To check attribute accuracy of the digital files we visually compared the original compilation against test plots of the files and corrected discrepancies between the digital geospatial dataset and the original analog as needed. The geologic interpretations presented in this report have undergone two technical reviews by a geologist familiar with the subject of the report and the geology of the map area. We incorporated the reviewer's suggestions into the final draft when deemed appropriate. Polygon topology is present and clean on the originating geospatial dataset. All polygon features were topologically validated using the ESRI ArcGIS 10+ software prior to export to shape file format. The logical consistency of the point and line files has been visually checked but not systematically verified. This dataset includes shapefiles that contain information surficial geologic units and fault traces mapped in this area. This data set utilizes field observations and air photo interpretations. It includes geospatial information about units traceable on air photos at a scale of ~1:65000 and/or in the field. The dataset displays: surficial geologic units and contacts, inferred geologic contacts, fault traces and point localities discussed in the text. Subsurface data available for this investigation include: about 10-15 soil pits dug to depths no more than 1.3 m; observations of exposures in gravel pits, highway cuts, and river bank; and several trench exposures excavated as part of work for an ADGGS preliminary interpretive report describing active faulting in this area. The active faults shown on the map sheets are more fully described in an ADGGS preliminary Interpretive Report by Carver and other (2010). The surficial interpretations were first hand-drawn, using a magnifying stereoscope, onto acetate air-photo overlays at the scale of the air-photos (approximately 1:63,360-scale). The accuracy of the map unit boundary locations varies due to the scale and interpretive nature of the mapping and pen line width of approximately 0.001 meters which is equivalent to approximately 1.5 meters on the ground. The hand drawn map unit boundaries are expected to be accurate to at least 15 meters. Following interpretation, acetate overlays were then individually scanned, orthorectified and georeferenced using Orthomapper, v. 3.6. The air-photos were orthorectified, photo-mosaiced and georeferenced. Surficial unit boundaries were digitized on-screen into ArcGIS from the orthorectified overlays at a scale more detailed than 1:63,360, using a combination of a USGS topographic 1:63.360 map layer and the air-photo photomosaic layer to verify the position of the lines and points. Map error is induced by: (1) Scanning and orthorectifying air photos and overlays. The digitizing RMS error is generally constrained to be less than 4 pixels, equating to approximately 20 m on the ground, although some areas with rugged terrain have larger errors. 2) On-screen digitizing from orthorectified overlays. The accuracy of the human operator digitizing polylines and point localities is related to the accuracy of interpretations from the orthorectified photos and overlays. Total horizontal accuracy of the mapped surficial-geologic contacts is thus on the order of 25 m or better, with somewhat lesser accuracy expected in areas of rugged relief. Coordinates of soil pits, radiocarbon sampling localities, and other field sites that are discussed in the text were recorded using a Garmin GPS model 76CSx with an estimated precision generally less than 10 meters. 25 mapped surficial-geologic contacts 10 soil pits and radiocarbon localities Kreig, R.A. Reger, R.D. 1976 book chapter Stroudsburg Dowden, Hutchinson, and Ross p. 55-76 Coates, D.R. 2011 document paper 1976 ground condition Kreig and Reger, 1976 Contains terrain evaluation for trans-Alaska oil pipeline Kreig, R.A. Reger, R.D. 1982 document Geologic Report GR-66 Fairbanks AK Alaska Division of Geological & Geophysical Surveys 149 p. paper 1982 ground condition Kreig and Reger, 1982 Contains air-photo analysis and landform soil properties for trans-Alaska oil pipeline Péwé, T.L. Reger, R.D. 1983 book chapter Guidebook Guidebook 1 Fairbanks AK Alaska Division of Geological & Geophysical Surveys in Péwé, T.L., and Reger, R.D., eds., Guidebook to permafrost and Quaternary geology along the Richardson and Glenn Highways between Fairbanks and Anchorage, Alaska, p. 5-45 Péwé, T.L., ed. Reger, R.D., ed. 1983 document Guidebook Guidebook 1 Fairbanks AK Alaska Division of Geological & Geophysical Surveys paper 1983 ground condition Pewe and Reger, 1983 Contains information about Quaternary geology of Tanana Valley Carter, L.D. Galloway, J.P. 1978 document Open-file report OF 78-794 United States U.S. Geological Survey 26 p., 3 map sheets, scale 1:125,000 paper 1978 ground condition Carter and Galloway, 1978 Engineering geologic maps at 1:125,000 Carver, G.A. Bemis, S.P. Solie, D.N. Obermiller, K.E. 200812 tabular digital data Preliminary Interpretive Report PIR 2008-3D Fairbanks AK Alaska Division of Geological & Geophysical 32 p. online 2007 ground condition Carver and others, 2008 Source of active faults in segment area just to east of present studyarea Duk-Rodkin, Alejandra Barendregt, R.W. Froese, D.G. Weber, Florence Enkin, Randy Smith, I.R. Waters, Pamela Klassen, Rudy 2004 book chapter Development in Quaternary Science v.2 New York Elsevier p. 313-345 Ehlers, J. Gibbard, P.L. 2004 book chapter Development in Quaternary Science v. 2 New York Elsevier p. 313-345 paper 2004 ground condition Duk-Rodkin and others, 2004 Information about timing of glaciation in Canada and Alaska Hamilton, T.D. 1994 book chapter Geology of North America v. G-1 United States Geological Society of America p. 813-844 Plafker, George Berg, H.C. 1994 book chapter Geology of North America v. G-1 United States Geological Society of America p. 813-844 paper 1994 ground condition Hamilton, 1994 Late Cenozoic glaciation of Alaska Holmes, G.W. 1965 document Bulletin B 1181-H United States U.S. Geological Survey 19 p., 1 map sheet, scale 1:125,000. paper 1965 ground condition Holmes, 1965 Geologic reconnaissance along the Alaska Highway, Delta River to Tok Junction Mason, O.K. Begét, J.E. 1991 journal article United States Arctic and Alpine Research v. 23, no. 4, p. 392-403. paper 1991 ground condition Mason and Beget, 1991 Holocene flooding in Tanana valley Péwé, T.L. 1975 document Professional Paper P 835 United States U.S. Geological Survey 145 p. paper 1975 ground condition Pewe, 1975 Quaternary geology of Alaska Weber, F.R. 1986 book chapter Anchorage, Alaska Alaska Geological Society p. 79-98. Hamilton, T.D., ed. Reed, K.M., ed. Thorson, R.M., ed. 1986 book chapter Anchorage, Alaska Alaska Geological Society p. 79-98. paper 1986 ground condition Weber, 1986 Glacial geology of the Yukon-Tanana Upland U.S. Geological Survey 1948 map Reston, VA U.S. Geological Survey scale 1:63,360 63360 All Topo software 1948 ground condition USGS Tanacross A-4, 1948- minor revisions 1973 base map U.S. Geological Survey 1949 map Reston, VA U.S. Geological Survey scale 1:63,360 63360 All Topo software 1949 ground condition USGS Tanacross B-4, 1949- minor revisions 1994 base map U.S. Geological Survey 1948 map Reston, VA U.S. Geological Survey scale 1:63,360 63360 All Topo software 1948 ground condition USGS Tanacross B-5, 1948- minor revisions 1994 base map U.S. Geological Survey 1949 map Reston, VA U.S. Geological Survey scale 1:63,360 63360 All Topo software 1949 ground condition USGS Tanacross B-6, 1949- minor revisions 1970 base map U.S. Geological Survey 1955 map Reston, VA U.S. Geological Survey scale 1:63,360 63360 All Topo software 1955 ground condition USGS Tanacross C-6, 1955- minor revisions 1982 base map U.S. Geological Survey Unknown prints and digital files Unknown U.S. Geological Survey 65000 photographic print 198008 197807 198307 ground condition AHAP Aerial Photography Aerial photography used in map unit interpretation Carrara, P.E. 2004 version 1 map U.S. Geological Survey Scientific Investigations Map 2850 Denver, CO US Geological Survey 1 map sheet 63360 paper 2004 ground condition Carrara, 2004a Contains geologic information about the Tanacross B-6 Quadrangle Carrara, P.E. 2004 version 1.0 map U.S. Geological Survey Scientific Investigations Map 2856 Denver, CO US Geological Survey 1 sheet 63360 paper 2004 ground condition Carrara, 2004b Contains geologic information about the Tanacross B-5 Quadrangle Carrara, P.E. 2006 version 1 map U.S. Geological Survey Scientific Investigations Map 2935 Denver, CO U.S. Geological Survey 1 sheet- 63,360 63360 paper 2004 ground condition Carrara, 2006 Contains geologic information about the tanacross B-4 Quadrangle Carver, G.A. Bemis, S.P. Solie, D.N. Castonguay, S.R. Obermiller, K.E. 2010 document Preliminary Interpretive Report PIR 2010-1 Fairbanks, AK Alaska Division of Geological & Geophysical Surveys paper 2010 ground condition Carver and others, 2010 Contains information about recent faulting activity in the area. Foster, H.L. 1970 map U.S. Geological Survey Miscellaneous Geologic Investigations Map I-593 united states U.S. Geological Survey 1 sheet 250000 paper 1970 ground condition Foster, 1970 Contains geologic information about the Tanacross Quadrangle Foster, H.L. Keith, T.E.C. 1969 document U.S. Geological Survey Bulletin B 1281 United States U. S. Geological Survey paper 1969 ground condition Foster and Keith, 1969 Contains information about geology along the Taylor Highway Grahek, M.E. Livingston, H.R. 1983 document United States Alaska Department of Transportation and Public Facilities paper 1983 ground condition Grahek and Livingston, 1983 Contains information about unconsolidated materials in the area Hemenway, K.T. Weaver, M. 2009 document United States Alaska Department of Transportation and Public Facilities paper 1983 ground condition Hemenway and Weaver, 1983 Contains information about unconsolidated materials in the area U.S. Geological Survey 1948 map Reston, VA U.S. Geological Survey scale 1:63,360 63360 All Topo Software 1949 ground condition USGS Tanacross A-5, 1949- minor revisions 1973 base map Aerial photograph interpretation - Stereo pairs of ~1:65000-scale, false-color infrared aerial photographs taken in July 1978, August 1980 and July 1983, as well as data from published and unpublished mapping of the target region and adjacent regions, were used to initially interpret and map the surficial geology. Unit boundaries were drawn by hand onto acetate overlays, using a magnifying stereoscope. Overlays were registered to aerial photos using tick marks on the photos. Krieg and Reger, 1976 Kreig and Reger, 1982 Carter and Galloway, 1978 Holmes, 1965 AHAP Aerial Photography Carrara, 2004a Carrara, 2004b Carrara, 2006 Foster, 1970 Foster and Keith, 1970 Grahek and Livingston, 1983 Hemenway and Weaver, 1983 Pewe and Reger, 1983 2008 Digital cartography - The acetate overlays were individually scanned and orthorectified, using Orthomapper, v. 3.6, and georeferenced. The air-photos were orthorectified, photomosaiced and georeferenced. Map unit boundaries were digitized on-screen into ArcGIS from the orthorectified overlays at a scale more detailed than 1:63,360, using a combination of a USGS topographic 1:63.360 map layer and the orthophotomosaic layer to verify the position of the lines. Surficial geology map polygons and lines were then edited and attributed using ArcMap 9+ USGS Tanacross A-4, 1948 USGS Tanacross A-5. 1949 USGS Tanacross B-4, 1949 USGS Tanacross B-5, 1948 USGS Tanacross B-6, 1949 USGS Tanacross C-6, 1955 AHAP Aerial Photography 2008 Fieldwork - Reconnaissance field work was done in the summer of 2007 during which observations were recorded for use during aerial photograph interpretation. In July-August 2008, field work to verify aerial photograph interpretations was performed. In addition to observations from ground and helicopter traverses, several soil pits were dug using shovels to maximum depth of 1.3 meters to observe soil profiles, and observations of exposures along river banks, highway cuts, and trenches dug as part of active fault studies were recorded. Pewe and Reger, 1983 Carver and others, 2008 Duk-Rodkin and others, 2004 Hamilton, 1994 Mason and Beget, 1991 Pewe, 1975 Weber, 1986 Carver and others, 2010 2008 Map compilation - The surficial geologic map was compiled using field notes from fieldwork process step (above), all known geologic data from previous work in the quadrangle and by additional aerial photographic interpretation. Changes to unit boundaries, after field work, were completed in ArcGIS. 9+. GIS files were exported and Adobe Illustrator and Microsoft Word were used to create the final map layout. 2011 Radiocarbon data - radiocarbon samples were collected during field work in the summer of 2008 by Dick Reger and Trent Hubbard. Samples were sent to Beta Analytic for analysis in early 2009 2009 Metadata creation - Metadata were assembled by T.D. Hubbard and P.E. Gallagher to FGDC Standards using Metavist 1.2, DGGS 7.05, a data entry program for FGDC metadata with XML output. 2011 Vector Universal Transverse Mercator 7 0.9996 -141 0 500000 0 coordinate pair 0.0000001 0.0000001 meters surf_geology Universal Transverse Mercator 7 0.9996 -141.00000 0 500000.0 0 coordinate pair 0.0000001 0.0000001 meters fault_features Universal Transverse Mercator 7 0.9996 -141.00000 0 500000.0 0 coordinate pair 0.0000001 0.0000001 meters border Universal Transverse Mercator 7 0.996 -141.0 0 500000.0 0 coordinate pair 0.0000000000000001 0.0000000000000000001 meters localities North American Datum of 1927 Clarke 1866 6378206.4 294.978698 border border.shp polygon outlining boundary of map area Alaska Division of Geological & Geophysical Surveys surf_geology surf_geology.shp polygons representing surficial-geologic map units Alaska Division of Geological & Geophysical Surveys unit_label Map unit label shown on map and described in text. Note that "?" indicates questionable identification. Map units shown in parenthesis such as (Qcf), indicate combination map units consisting of bedrock overlain by thin to discontinuous material of the map unit shown. Alaska Division of Geological & Geophysical Surveys PIR2009-6A-unit descriptions This Report lake unit is a lake This report fault_features fault_features.shp Trace of identified active faults Alaska Division of Geological & Geophysical Surveys fault Type of fault feature Alaska Division of Geological & Geophysical Surveys Anticline, approximate Approximate location of anticline This report Anticline, certain Certain location of Anticline This report High Angle, concealed Location of High Angle fault where concealed. This report Thrust, approximate Approximate location of Thrust fault This report Thrust, certain Certain location of Thrust fault This report. Thrust, concealed Location of Thrust fault where concealed This report High Angle, approximate Approximate location of High Angle fault This report High Angle, certain Certain location of High Angle fault This report Anticline, concealed Location of anticline where concealed This report descriptn fault feature description Alaska Division of Geological & Geophysical Surveys Description of fault feature shown on map: localities localities.shp location of soil pits, radiocarbon samples, map localities and ventifact locality discussed in the text Alaska Division of Geological & Geophysical Surveys Type Type of locality Alaska Division of Geological & Geophysical Surveys Radio Carbon Radio Carbon locality discussed in text This report Point Locality Point locality discussed in text This report Soil Pit Soil Pit locality discussed in text This report Ventifact Site Ventifact site discussed in text This report Label Label used to identify each locality Alaska Division of Geological & Geophysical Surveys Label, SP indicates Soil Pit, RC indicates Radio Carbon, V indicates Ventifact site, and A,B, or C indicates Point locality State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys mailing and physical

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Fairbanks AK 99709-3707 USA 907-451-5020 907-451-5050 dggspubs@alaska.gov 8 am to 4:30 pm, Monday through Friday, except State holidays Please view our website (http://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. The State of Alaska makes no express or implied warranties (including warranties of merchantability and fitness) with respect to the character, function, or capabilities of the electronic services 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, any failure thereof, or otherwise, and in no event will the State of Alaska's liability to the requester or anyone else exceed the fee paid for the electronic service or product. The current publication may be available on paper. 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.Turn around 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. see http://www.dggs.alaska.gov/pubs/id/19741 SHP http://www.dggs.alaska.gov/pubs/id/19741 Free download 20111207 Metadata manager mailing and physical

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