A Guide to the Late Quaternary History of Northern and Western Kenai Peninsula, Alaska

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

High-resolution lidar data for the Whittier area, Passage Canal, and Portage Lake, Alaska

In support of geologic mapping and hazards evaluation in and near Whittier, Alaska, the Division of Geological & Geophysical Surveys (DGGS) acquired, and is making publicly available, lidar (light detection and ranging) data for an area along Passage Canal, Portage Lake, and Portage Glacier Highway. The lidar data, acquired and processed by Watershed Sciences, Inc. (WSI) consist of continuous coverage encompassing an area extending from Portage Lake eastward to Logging Company Bay in Passage Canal in the Seward D-4, D-5, and D-6 1:63,360-scale quadrangles. Lidar data collected below 1,600 ft (488 m) elevation have a minimum average pulse density of 8 pulses/square meter; above 1,600 ft (488 m) data were collected...

Tags: Aerial Geology, Alaska, State of, Aleutian Islands, Bare-Earth Digital Elevation Model (DEM), City of Whittier Coastal District, All tags... Digital Elevation Model, Digital Surface Model (DSM), Geologic Hazards, Geology, Geomorphology, Hazards, Highest Hit Digital Surface Model (DSM), Hillshade Image, Lidar, Lidar Intensity Image, Lidar LAS File Format, Passage Canal, Point Cloud Data, Raster Image, Raster Index Shapefile, Remote Sensing, Seward, Seward Quadrangle, Slope Instability, Vegetation Digital Surface Model (DSM), Whittier, geoscientificInformation, Fewer tags

Top Mesozoic unconformity subcrop map, Cook Inlet basin, Alaska

This map shows the subcrop pattern of the Mesozoic rock units present at the top Mesozoic unconformity (also commonly referred to as the base Tertiary unconformity) in Cook Inlet basin, Alaska. The subcrop is projected onto the top Mesozoic unconformity depth surface of Cook Inlet basin, Alaska, published by Shellenbaum and others (2010). Publicly available geologic and geophysical data from multiple sources were collected, interpreted, and integrated into the subcrop map. Formation picks at the top Mesozoic unconformity were determined for 109 wells. Mesozoic horizons from two regional marine two-dimensional (2-D) seismic datasets (approximately 3,300 miles) were interpreted. Eight map units were established for...

Tags: Anchorage, Anchorage Quadrangle, Bedrock Geologic Map, Bedrock Geology, Bibliography, All tags... Biostratigraphy, Cook Inlet, Cook Inlet Basin, Core Logs, Correlation, Depth Interpretation, Drill Logs, Drilling, Energy, Energy Resources, Folds, Forearc Basin, Geologic, Geologic Map, Geology, Geophysical Logs, Geophysics, Gis, Homer, Hydrocarbon, Hydrocarbon Potential, Igneous Rocks, Iliamna Quadrangle, Iniskin Bay, Inoceramus, Interpretation, Kenai, Kenai Peninsula, Kenai Quadrangle, Lake Clark Quadrangle, Matanuska River, Matanuska Valley, Metamorphic Rocks, Mount Katmai Quadrangle, Oil Basins, Oil and Gas, Oil and Gas Basin, Palmer, Palynology, Petroleum, Petroleum Basin Study, Port Graham, Reservoir, Resources, Rock Units, Saddle Mountain, Sedimentary Rocks, Seismic Interpretation, Seldovia, Seward, Seward Quadrangle, Source Rock, Southcentral Alaska, Stratigraphy, Strike-Slip, Structural Geology, Structure, Structure Contours, Structure Map, Subsurface, Surface, Susitna River, Talkeetna Mountains Quadrangle, Talkeetna Quadrangle, Thrust, Tuxedni Bay, Tyonek, Tyonek Quadrangle, Unconformity, Volcanic Rocks, Wasilla, Well Logs, geoscientificInformation, Fewer tags

40Ar/39Ar ages of rocks collected from the Passage Canal area, Seward D-7 Quadrangle, Alaska

This report presents 40Ar/39Ar step-heating geochronology results from a single outcrop of a mineralized near-trench intrusion exposed in a road cut near Whittier, Alaska. The outcrop is the best road-accessible occurrence of a Tertiary near-trench pluton in the region and is commonly visited by field trips, yet no prior geochronological data from this outcrop have been published. Two chronologically distinct intrusive bodies, the Paleogene Sanak-Baranof belt and the Eshamy-suite, are documented in the upper Cook Inlet area. Geochronological analysis of the two samples described in this report confirms that the Whittier road-cut intrusion and veins are coeval (53.0 +/- 0.3 Ma and 50.9 +/- 0.2 Ma, respectively) with...

Tags: 40Ar/39Ar, Age Dates, Analyses, Analyses and Sampling, Analytical Lab Results, All tags... Analytical Results, Ar-Ar, Bedrock, Bedrock Geology, Geochronology, Geologic, Geology, Igneous, Igneous Rocks, Isotopes, Lab Methods, Methods, Mineralogy, Rocks, Sample Location, Seward Quadrangle, Volcanic Arc, Volcanic Rocks, Whittier, geoscientificInformation, Fewer tags