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A physiographically prominent, approximately 40 square km plateau lies roughly 20 km east of Mount Spurr volcano, northwestern Cook Inlet region, Alaska, and comprises the preserved remnant of a volcaniclastic succession, designated in this study as map unit Qvc. Although this readily mappable package of volcaniclastic rocks has been recognized in numerous studies during the past five decades, uncertainties regarding its age and origin have persisted. We describe the general characteristics of the volcaniclastic plateau, provide new age constraints for deposits, present lithofacies descriptions and interpretations of the volcaniclastic strata, and synthesize our observations and lithofacies analysis to propose an...
Tags: Age Dates,
Alluvial,
Alluvial Deposits,
Bedrock,
Bedrock Geology, All tags...
Capps Glacier,
Debris Flow,
Debris Flow Deposit,
Depositional Environment,
Depositional Environments,
Detrital Zircon,
Facies Analysis,
Geochronology,
Geological Process,
Geology,
Lahar,
Lahar Runout Flow,
Liquefaction,
Mount Spurr,
Paleoenvironment,
Paleogeography,
STATEMAP Project,
Sediment Transport,
Sedimentary,
Sedimentary Rocks,
Sedimentation,
Sedimentology,
Tyonek Quadrangle,
U-Pb,
Volcaniclastics,
geoscientificInformation, Fewer tags
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During 2009, 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. The study area is a 12-mi-wide (19.3-km-wide) area that straddles the Alaska Highway from the western boundaries of the Tanacross B-3 and A-3 quadrangles near Tetlin Junction eastward to the eastern boundaries of the Nabesna D-1 and C-1 quadrangles along the Canada border. Mapping during 2008-2009 in the Tanacross and Nabesna quadrangles linked with the mapping completed in the Tanacross, Big Delta and Mt. Hayes quadrangles in 2006-2008. Surficial geology was initially mapped in...
Tags: Aeolian,
Alaska Highway Corridor,
Alaska Pipeline,
Alaska, State of,
Beaver Creek, All tags...
Canada,
Chisana River,
Engineering,
Engineering Geology,
Eolian,
Gasline,
Geologic Hazards,
Geologic Map,
Geology,
Hazards,
Landslide,
Landslide Deposit,
Loess,
Midway Lake,
Nabesna,
Nabesna Quadrangle,
Nabesna River,
Natural Gas,
Northway,
Northway Junction,
Periglacial Slope Failure,
Permafrost,
Pipeline,
Proposed Natural Gas Pipeline,
Retransported Loess,
Scottie Creek,
Tanacross Quadrangle,
Tanana Basin,
Tanana River,
Taylor Highway,
Tetlin,
Tetlin Junction,
Tetlin National Wildlife Refuge,
Thawing Permafrost,
Translational Landslide,
Transportation Corridor,
Unconsolidated Deposits,
geoscientificInformation, Fewer tags
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This map illustrates extents and types of unconsolidated deposits and bedrock in the Big Delta A-4 Quadrangle, Alaska. This map is based on field observations begun by P�w� in 1949 and by Reger in 1976. Unit characteristics and extents were determined during field visits and by interpreting 1:40,000-scale black-and-white aerial photographs taken in August 1949 and 1:63,360-scale, false-color infrared aerial photographs taken in July 1978, August 1980, and August 1981.
Tags: Alaska Range,
Alluvium,
Big Delta,
Big Delta Quadrangle,
Delta River, All tags...
Geology,
Glaciation,
Loess,
Outwash,
Permafrost,
Radiocarbon Dating,
Silt,
Surficial Geology,
Tanana River,
Tephra,
Till,
geoscientificInformation, Fewer tags
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Between 27 and 11 kyr ago, during the last major (Naptowne) glaciation, the northwestern and western Kenai Peninsula and the Cook Inlet trough were covered by ice except for local nunataks and small refugia, like the Caribou Hills. Landforms related to four glacial stades are recognized and paleogeographic maps document ice limits, drainage systems, glacial-impounded lakes, and glaciomarine terraces. Numerous multidisciplinary studies of glacial, vegetation, and insect histories document Holocene climatic changes.
Tags: Alluvial Deposits,
Climate Change,
Coastal Erosion,
Cook Inlet,
Erosion, All tags...
Geologic Hazards,
Geology,
Geomorphology,
Glacial Deposits,
Glacial Drift,
Glacial Geology,
Glaciation,
Gravel,
Homer,
Ice,
Ice Contact Deposits,
Ice-Contact,
Kenai Peninsula,
Kenai Quadrangle,
Kenai Spur Highway,
Meltwater,
Outwash,
Radiocarbon Dating,
Seldovia Quadrangle,
Seward Highway,
Seward Quadrangle,
Sterling Highway,
Surficial Geology,
Tephra,
Tephrachronology,
Terrace,
Tsunami,
Vegetation,
geoscientificInformation, Fewer tags
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The engineering-geologic map is derived electronically, using Geographic Information System (GIS) software, from the surficial-geologic map of the second segment of the proposed natural gas pipeline corridor through the upper Tanana valley, a 12-mi-wide (19.3-km-wide) area that straddles the Alaska Highway through the upper Tanana River valley from the Robertson River eastward to near Tetlin Junction in the Tanacross Quadrangle (Reger and Hubbard, PIR 2009-6A). Surficial-geologic units were initially identified by interpretation of false-color ~1:65,000-scale infrared aerial photographs taken in July 1978, August 1980, and August 1981 and locally verified by field checking in 2007 and 2008. The map shows the distribution...
Tags: Alaska Highway Corridor,
Alaska Range,
Alaska, State of,
Alluvial Deposits,
Climate Change, All tags...
Colluvial Deposits,
Construction Materials,
Crushed Gravel,
Crushed Rock,
Dot Lake,
Engineering,
Engineering Geology,
Floodplain,
Floods,
Gasline,
Geologic Hazards,
Geologic Map,
Geologic Materials,
Icings,
Land Subsidence,
Landslide,
Liquefaction,
Materials Site,
Permafrost,
Proposed Natural Gas Pipeline,
Robertson River,
Sand & Gravel,
Subsidence,
Surficial Geology,
Tanacross,
Tanacross Quadrangle,
Taylor Highway,
Tok,
Tok River,
Transportation Corridor,
Unconsolidated Deposits,
geoscientificInformation, Fewer tags
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