Geologic context, age constraints, and sedimentology of a Pleistocene volcaniclastic succession near Mount Spurr volcano, south-central Alaska

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

Surficial geology of the Tyonek area, south-central Tyonek Quadrangle, Alaska

The Tyonek area in the northwestern Cook Inlet trough is rich in petroleum, coal, geothermal, aggregate, and timber resources, but the detailed geologic mapping necessary for planning future resource development exists only in part of the area. This report and geologic map provide basic surficial-geologic information useful for exploiting those resources and planning future utility corridor developments. In addition to mapping of surficial geologic units, we provide discussion of strategraphic evidence pertaining to physiographic relations and geologic history of volcaniclastic deposits derived from ancestral Mount Spurr, multiple phases of Quaternary glacial activity, Chakachatna River valley landslide complexes...

Tags: Alaska Earthquake 1964, Alluvial Fan, Beluga Plateau, Beluga River, Blockade Glacier, All tags... Capps Glacier, Chakachatna River, Chakachatna-McArthur Embayment, Chalcedony, Chigmit Mountains, Chuitna Coal Project, Chuitna River, Coastal Plain, Colluvium, Cook Inlet, Cook Inlet Basin, Correlation, Debris Avalanche, Depositional Environment, Diamictons, Earthquake Related Slope Failure, Erratics, Fault Displacement, Glacial Geology, Glacier Outburst Flood, Glacioestuarine Deposits, Jasper, Jokulhlaup, Lahar, Landslide Deposit, Little Ice Age, Moraines, Mount Spurr, Neacola Mountains, Neoglacial, Neotectonics, Penultimate Glaciation, Radiocarbon Ages, Rotational Landslide, STATEMAP Project, Sediment Gravity Flow, Straight Creek, Surface Fault Rupture, Surficial Geologic Map, Surficial Geology, Susitna Lowland, Tectonics, Threemile Creek, Till, Tordrillo Mountains, Tyonek, Tyonek Quadrangle, Volcaniclastic Deposits, geoscientificInformation, Fewer tags

Petrology and reservoir potential of Tertiary and Mesozoic sandstones, Cook Inlet, Alaska: A preliminary analysis of outcrop samples collected during 2007-2010 field seasons

The State of Alaska Division of Geological & Geophysical Surveys (DGGS) and Division of Oil & Gas (DOG) are currently engaged in a multi-year study of the hydrocarbon potential of the Tertiary and Mesozoic strata in Cook Inlet basin. Modal analyses and routine core analyses were performed on Tertiary and Mesozoic siltstones and sandstones collected during the 2007-2010 field seasons from six geographic areas in upper and lower Cook Inlet. The reservoir quality of Cook Inlet sandstones varies widely depending on their mineralogy, geologic age, burial depth, and depositional environment. Tuxedni and Naknek sandstones have poor reservoir quality and are likely to be of equally poor quality down dip. West Foreland sandstones...

Tags: Aleutian Arc, Beluga Basin, Bluff Point, Capps Glacier, Chert, All tags... Chuitna River, Clam Gulch, Cook Inlet, Cook Inlet Basin, Diagenesis, Falls Creek, Feldspar, Fritz Creek, Graywacke, Homer, Iniskin Bay, Iniskin Peninsula, Kachemak Bay, Kaguyak, Matanuska Valley, Mineralogy, Oil Basins, Oil and Gas, Oil and Gas Basin, Outcrop Samples, Permeability, Petrographic, Petrography, Petroleum Basin Study, Petrology, Porosity, Provenance, Pyroclastic Fall, Pyroclastic Flow, Quartz, Reservoir, Reservoir Evaluation, Reservoir Quality, Resource Assessment, Saddle Mountain, Sample Location, Sample Location Map, Sand, Sand and Gravel, Sediment Transport, Sedimentary, Sedimentary Rocks, Sedimentation, Sedimentology, Seward Peninsula, Southcentral Alaska, Straight Creek, Tectonics, Thin Section, Tyonek, Tyonek Quadrangle, Volcanic, Volcanic Ash, Volcaniclastics, Zeolites, geoscientificInformation, Fewer tags