Filters: Tags: Aleutian Islands (X) > partyWithName: Alaska Division of Geological & Geophysical Surveys (X)

Filters Date Range Past year (0) Past month (0) Past week (0) Past day (0) Custom range... To   Search Contacts Cameron, C.E. Nye, C.J. Schaefer, J.R. Koehler, R.D. Nicolsky, D.J. More... Tag Types Theme (12) Place (12) Tag Schemes Alaska Division of Geological & Geophysical Surveys (12) ISO 19115 Topic Category (12) View Results as: JSON ATOM CSV

Tsunami inundation maps for the city of Sand Point, Alaska Staff from Alaska Earthquake Center, Geophysical Institute and Alaska Division of Geological & Geophysical Surveys evaluated potential tsunami hazards for the city of Sand Point, on Popof Island in the Shumagin Islands archipelago. We numerically modeled the extent of inundation from tsunami waves generated by local and distant earthquake sources. We considered the results in light of historical observations. The worst-case scenarios are defined by analyzing results of the sensitivity study of the tsunami dynamics with respect to different slip distributions along the Aleutian megathrust. For the Sand Point area, the worst-case scenarios are thought to be thrust earthquakes in the Shumagin Islands region with magnitudes... Tags: Active Fault, Alaska Earthquake 1964, Aleutian Islands, Bathymetry, Coastal, All tags... Coastal and River, Earthquake, Emergency Preparedness, Engineering, Engineering Geology, Fault Displacement, Faulting, Faults, Flood, Geologic Hazards, Geology, Hazards, Humboldt Harbor, Inundation, Land Subsidence, Modeling, Popof Island, Raster Image, Sand Point, Seismic Gap, Seismic Hazards, Seismology, Shumagin Islands, Surface, Topography, Tsunami, Water, geoscientificInformation, Fewer tags Historically active volcanoes of Alaska This data lists the historically active volcanoes of Alaska and the year of the last major eruptive event. The volcanoes listed meet at least one of the following criteria since 1700 CE: (1) documented, unquestioned eruption, or (2) a strongly suspected eruption, often an eruption documented in the historical account with very little information (current geologic knowledge must not contradict the eruption account), or (3) persistent (usually on the order of decades, but certainly longer than several months) fumaroles, with temperatures (where measured) within ~10 degrees C of the boiling point, or (4) significant, measured, volcanic-related, non-eruptive deformation, (5) documented earthquake swarm with strongly... Tags: Active Volcanoes, Alaska Peninsula, Alaska Statewide Maps, Alaska, State of, Aleutian Arc, All tags... Aleutian Islands, Coastal and River, Coastal and River Hazards, Geologic Hazards, Geology, Hazards, Historic Eruption, Volcanic, Volcanic Eruption, Volcano Hazards, Volcanoes, Volcanology, geoscientificInformation, Fewer tags Geology of Kasatochi volcano, Aleutian Islands, Alaska Kasatochi is a small, isolated island volcano in the center of the Aleutian Island chain. It consists of a roughly circular cone approximately 3 km in diameter with a lake-filled central crater that is 1.2 km in diameter and extends from the highest point on the island to sea level. The oldest unit recognized is a thick series of mid-Pleistocene glaciovolcanic deposits consisting of autobrecciated lava, lahars, and volumetrically minor lava masses that we believe to have been emplaced underneath a regional ice cap. This unit is unconformably overlain by several massive Holocene lavas, above which lies a thick sequence of latest-Holocene pyroclastic deposits likely deposited during the crater-forming eruption. The... Tags: Active Volcanoes, Age Dates, Aleutian Arc, Aleutian Islands, Alluvial Deposits, All tags... Analyses, Analyses and Sampling, Basalt, Bedrock, Bedrock Geology, Caldera, Chemistry, Colluvium, Erosion, Fan, Geochemical Data, Geochemistry, Geochronology, Geologic, Geologic Hazards, Geologic Map, Geological Process, Geology, Geomorphology, Hazards, Historic Eruption, Igneous, Kasatochi, Lava Flow, Mineralogy, Petrographic, Petrography, Petrology, Pumice, Pyroclastics, Rockfall, Rocks, Sample Location, Slope Instability, Slump, Soils, Surface, Surficial, Talus, Tephra, Topography, Ultramafic, Uplift, Volcanic, Volcanic Ash, Volcanic Eruption, Volcanic Rocks, Volcaniclastics, Volcanoes, Volcanology, geoscientificInformation, Fewer tags The 2008 phreatomagmatic eruption of Okmok Volcano, Aleutian Islands, Alaska: Chronology, deposits, and landform changes Okmok volcano, Aleutian Islands, Alaska, explosively erupted over a five-week period between July 12 and August 23, 2008. The eruption was predominantly phreatomagmatic, producing fine-grained tephra that covered most of northeastern Umnak Island. The eruption had a maximum Volcanic Explosivity Index (VEI) of 4, with eruption column heights up to 16 km during the opening phase. Several craters and a master tuff cone formed in the caldera as a result of phreatomagmatic explosions and accumulated tephra-fall and surge deposits. Ascending magma continuously interacted with an extensive shallow groundwater table in the caldera, resulting in the phreatomagmatic character of the eruption. Syneruptive explosion and collapse... Tags: Active Volcanoes, Aleutian Arc, Aleutian Islands, Ash Cloud, Ash Fall, All tags... Caldera, Cone A, Cone B, Cone C, Cone D, Cone E, Cone F, Cone G, Cone H, Cone I, Cone J, Fort Glenn, Geologic Hazards, Geomorphology, Geothermal, Groundwater, Heat Flow Study, Historic Eruption, Lahar, Lahar Runout Flow, Lake Level, Okmok, Okmok Caldera, Okmok Hot Springs, Okmok Volcano, Okmok, Mount, Stratigraphy, Surface Water, Tephra, Umnak Island, Umnak Quadrangle, Unalaska Quadrangle, Volcanic Ash, Volcanic Eruption, Volcaniclastics, Volcanology, 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 Tsunami inundation map for the village of Nikolski, Alaska Potential tsunami hazard for the Umnak Island community of Nikolski is evaluated by numerically modeling the extent of inundation from tsunami waves generated by hypothetical earthquake sources. Worst-case hypothetical scenarios are defined by analyzing results of a sensitivity study of the tsunami dynamics related to various slip distributions along the Aleutian megathrust. The worst-case scenarios for Nikolski are thought to be thrust earthquakes in the Umnak Island region with their greatest slip at 10-30 km (6.2-19 mi) depth. We also consider Tohoku-type ruptures and an outer-rise rupture in the area of Umnak Island. The maximum predicted water depth on Main Street is about 15 m (49 ft), while the maximum current... Tags: Active Fault, Aleutian Islands, Coastal, Coastal and River Hazards, Earthquake, All tags... Earthquake Related Hazards, Emergency Preparedness, Engineering Geology, Fault Displacement, Faulting, Flood, Geologic Hazards, Hazards, Inundation, Land Subsidence, Modeling, Nikolski, Raster Image, Seismic Gap, Seismic Hazards, Tsunami, geoscientificInformation, Fewer tags Preliminary database of Quaternary vents in Alaska The Alaska Volcano Observatory (AVO) uses an informal set of names for about 140 'volcanoes.' Some names refer to large, complex volcanic centers, while others indicate only a specific cone. This publication expands the list of 140 named volcanoes to include all volcanic vents where magma has reached the surface over the past 2.6 million years. This database of all known (published, or unpublished with permission) Quaternary volcanic vents was developed to better describe the nature and character of Quaternary volcanism in Alaska and specifically to aid in the discussion of spatial and temporal patterns of Alaska volcanism. This list is a preliminary starting point, and we hope that it is updated and expanded by... Tags: Adak Quadrangle, Alaska Peninsula, Aleutian Islands, Amukta Quadrangle, Atka Quadrangle, All tags... Baird Inlet Quadrangle, Bendeleben Quadrangle, Candle Quadrangle, Chignik Quadrangle, Cold Bay Quadrangle, Cook Inlet, Craig Quadrangle, Fairbanks Quadrangle, False Pass Quadrangle, Gareloi Island Quadrangle, Goodnews Bay Quadrangle, Gulkana Quadrangle, Hazards, Healy Quadrangle, Hooper Bay Quadrangle, Iliamna Quadrangle, Karluk Quadrangle, Kenai Quadrangle, Ketchikan Quadrangle, Kiska Quadrangle, Kotzebue Quadrangle, Kwiguk Quadrangle, Lake Clark Quadrangle, Marshall Quadrangle, McCarthy Quadrangle, Mount Katmai Quadrangle, Nabesna Quadrangle, Naknek Quadrangle, Nunivak Island Quadrangle, Petersburg Quadrangle, Port Moller Quadrangle, Pribilof Islands Quadrangle, Rat Islands Quadrangle, Saint Lawrence Quadrangle, Saint Michael Quadrangle, Samalga Island Quadrangle, Seguam Quadrangle, Selawik Quadrangle, Seward Peninsula, Sitka Quadrangle, Southeast Alaska, Stepovak Bay Quadrangle, Sutwik Island Quadrangle, Tanacross Quadrangle, Tyonek Quadrangle, Ugashik Quadrangle, Umnak Quadrangle, Unalakleet Quadrangle, Unalaska Quadrangle, Unimak Quadrangle, Valdez Quadrangle, Volcanic Eruption, Volcanoes, Volcanology, Wrangell Mountains, geoscientificInformation, Fewer tags Tsunami inundation maps for King Cove and Cold Bay communities, Alaska Potential tsunami hazards for the Alaska Peninsula communities of King Cove and Cold Bay were evaluated by numerically modeling the extent of inundation from tsunami waves generated by hypothetical earthquake sources and taking into account historical observations. Worst-case hypothetical scenarios are defined by analyzing the tsunami dynamics related to various slip distributions along the Aleutian megathrust. Our results show that the worst-case scenarios for King Cove and Cold Bay are thrust earthquakes in the western Alaska Peninsula region, with magnitudes ranging from Mw 8.9 to Mw 9.3, which have their greatest slip at 10-20 km (6-12 mi) depth. We also consider Tohoku-type ruptures and an outer-rise rupture... Tags: Active Fault, Alaska Peninsula, Aleutian Islands, Coastal, Coastal and River Hazards, All tags... Cold Bay, Earthquake, Earthquake Related Hazards, Emergency Preparedness, Engineering Geology, Fault Displacement, Faulting, Flood, Geologic Hazards, Hazards, Inundation, King Cove, Land Subsidence, Landslide, Modeling, Raster Image, Seismic Gap, Seismic Hazards, Tsunami, geoscientificInformation, Fewer tags Kasatochi Island 2009 topography The 2008 eruption of Kasatochi volcano caused major topographic changes to Kasatochi Island, making all prior topographic maps and data obsolete. The topographic map and data presented here are derived from stereoscopic satellite images acquired on April 18, 2009. Subsequent topographic data has not been acquired, although there has been substantial topographic modification to the island, particularly to the shoreline, since these data were acquired. Tags: Aleutian Islands, Atka Quadrangle, Digital Elevation Model, Geodatabase, Geology, All tags... Geomorphology, Kasatochi, Satellite, Shaded Relief, Surface, Topography, Volcanoes, geoscientificInformation, Fewer tags Preliminary volcano-hazard assessment for Fisher volcano, Unimak Island, Alaska Fisher volcano, containing the largest Holocene caldera in the Aleutian volcanic arc, is an active volcano near the center of Unimak Island, about 120 kilometers southwest of Cold Bay and about 175 kilometers northeast of Dutch Harbor. The volcano is composed of numerous small volcanic centers around and within a large, oval caldera 12 by 18 kilometers in diameter and 500 to 1,000 meters deep that formed during a catastrophic eruption about 9,400 years ago. Since then, more than 30 separate vents inside and outside the caldera have erupted; the most recent eruption occurred in 1826. These eruptions have produced lava flows and widespread tephra (volcanic ash) deposits, and have occasionally been accompanied by large... Tags: Active Volcanoes, Aleutian Arc, Aleutian Islands, Ash Cloud, Ash Fall, All tags... Ballistics, Caldera, Debris Flow, Fisher, Flood, Geologic Hazards, Geothermal, Hazards, Lahar, Lava Flow, Pumice, Pyroclastic Flow, Pyroclastic Surge, Tephra, Unimak Quadrangle, Volcanic Ash, Volcanic Gas, Volcaniclastics, Volcanology, geoscientificInformation, Fewer tags Geology of Kasatochi volcano, Aleutian Islands, Alaska Kasatochi is a small, isolated island volcano in the center of the Aleutian Island chain. It consists of a roughly circular cone approximately 3 km in diameter with a lake-filled central crater that is 1.2 km in diameter and extends from the highest point on the island to sea level. The oldest unit recognized is a thick series of mid-Pleistocene glaciovolcanic deposits consisting of autobrecciated lava, lahars, and volumetrically minor lava masses that we believe to have been emplaced underneath a regional ice cap. This unit is unconformably overlain by several massive Holocene lavas, above which lies a thick sequence of latest-Holocene pyroclastic deposits likely deposited during the crater-forming eruption. The... Tags: Active Volcanoes, Age Dates, Aleutian Arc, Aleutian Islands, Alluvial Deposits, All tags... Analyses, Analyses and Sampling, Basalt, Bedrock, Bedrock Geology, Caldera, Chemistry, Colluvium, Erosion, Fan, Geochemical Data, Geochemistry, Geochronology, Geologic, Geologic Hazards, Geologic Map, Geological Process, Geology, Geomorphology, Hazards, Historic Eruption, Igneous, Kasatochi, Lava Flow, Mineralogy, Petrographic, Petrography, Petrology, Pumice, Pyroclastics, Rockfall, Rocks, Sample Location, Slope Instability, Slump, Soils, Surface, Surficial, Talus, Tephra, Topography, Ultramafic, Uplift, Volcanic, Volcanic Ash, Volcanic Eruption, Volcanic Rocks, Volcaniclastics, Volcanoes, Volcanology, geoscientificInformation, Fewer tags Historically active volcanoes of Alaska This data lists the historically active volcanoes of Alaska and the year of the last major eruptive event. The volcanoes listed meet at least one of the following criteria since 1700 CE: 1) Documented, unquestioned eruption OR 2) A strongly suspected eruption, often an eruption documented in a historical account with very little information. Current geologic knowledge must not contradict the eruption account, OR 3) Persistent (usually on the order of decades, but certainly longer than several months) fumaroles, with temperatures (where measured) within approximately 10 degrees C of the boiling point, OR 4) Significant, measured, volcanic-related, non-eruptive deformation, OR 5) Documented earthquake swarm with strongly... Tags: Active Volcanoes, Alaska Peninsula, Alaska Statewide Maps, Alaska, State of, Aleutian Arc, All tags... Aleutian Islands, Coastal and River, Coastal and River Hazards, Geologic Hazards, Geology, Hazards, Historic Eruption, Volcanic, Volcanic Eruption, Volcano Hazards, Volcanoes, Volcanology, geoscientificInformation, Fewer tags