Filters: Tags: Geologic Hazards (X) > partyWithName: Alaska Division of Geological & Geophysical Surveys (X)
66 results (7ms)|
Filters
Date Range
Contacts Tag Types Tag Schemes |
The Geologic Map Index of Alaska (Map Index) is an online, interactive web mapping application that provides access to an actively growing geographic index of geology-related maps of Alaska and adjacent areas. This online research tool provides the locations and outlines of most DGGS and U.S. Geological Survey (USGS) geologic and geophysical maps of Alaska in a single, interactive web map. It allows searches of the map database by geographic area of interest, keywords, themes, publishing agency, dates, and other criteria. The search results provide links to DGGS's comprehensive, multi-agency publications database, where users may view and download publications for free. No other geographic index of Alaska geologic...
Photogrammetric digital surface models and orthoimagery for 26 coastal communities of western Alaska
The State of Alaska Division of Geological & Geophysical Surveys acquired photogrammetric digital surface models (DSMs) and co-registered orthorectified aerial images (orthoimages) for the west coast of Alaska in support of coastal vulnerability mapping efforts. This report is a summary of the data collected over 26 developed areas along approximately 3,500 km of coastline in the Bering Sea, Norton Sound, and Yukon-Kuskokwim Delta regions (fig. 1). Aerial photographs were collected between July 31 and September 6, 2015, and processed using Structure from- Motion (SfM) photogrammetry techniques. Ground control points (GCPs) and checkpoints were collected in support of these data products during a Global Navigation...
The purpose of this study is to evaluate tsunami hazard for the community of Seward and northern Resurrection Bay area, Alaska. This report will provide guidance to local emergency managers in tsunami hazard assessment. We used a numerical modeling method to estimate the extent of inundation by tsunami waves generated from earthquake and landslide sources. Our tsunami scenarios included a repeat of the tsunami of the 1964 Great Alaska Earthquake, as well as tsunami waves generated by two hypothetical Yakataga Gap earthquakes in northeastern Gulf of Alaska, hypothetical earthquakes in Prince William Sound and Kodiak asperities of the 1964 rupture, and local underwater landslides in Resurrection Bay. Results of numerical...
Potential tsunami hazards for the Fox Islands communities of Unalaska/Dutch Harbor and Akutan 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 results of a sensitivity study of the tsunami dynamics related to various slip distributions along the Aleutian megathrust. The worst-case scenarios for Unalaska and Akutan are thought to be thrust earthquakes in the Fox Islands region with magnitudes ranging from Mw 8.8 to Mw 9.1 that have their greatest slip at 30-40 km (18-25 mi) depth. We also consider Tohoku-type ruptures and an outer-rise...
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...
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...
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...
In advance of design, permitting, and construction of a pipeline to deliver North Slope natural gas to out-of-state customers and Alaska communities, the Division of Geological & Geophysical Surveys (DGGS) has acquired LiDAR (Light Detection and Ranging) data along proposed pipeline routes, nearby areas of infrastructure, and regions where significant geologic hazards have been identified. LiDAR data will serve multiple purposes, but have primarily been collected to (1) evaluate active faulting, slope instability, thaw settlement, erosion, and other engineering constraints along proposed pipeline routes, and (2) provide a base layer for the state-federal GIS database that will be used to evaluate permit applications...
In advance of design, permitting, and construction of a pipeline to deliver North Slope natural gas to out-of-state customers and Alaska communities, the Division of Geological & Geophysical Surveys (DGGS) has acquired LiDAR (Light Detection and Ranging) data along proposed pipeline routes, nearby areas of infrastructure, and regions where significant geologic hazards have been identified. LiDAR data will serve multiple purposes, but have primarily been collected to (1) evaluate active faulting, slope instability, thaw settlement, erosion, and other engineering constraints along proposed pipeline routes, and (2) provide a base layer for the state-federal GIS database that will be used to evaluate permit applications...
In advance of design, permitting, and construction of a pipeline to deliver North Slope natural gas to out-of-state customers and Alaska communities, the Division of Geological & Geophysical Surveys (DGGS) has acquired LiDAR (Light Detection and Ranging) data along proposed pipeline routes, nearby areas of infrastructure, and regions where significant geologic hazards have been identified. LiDAR data will serve multiple purposes, but have primarily been collected to (1) evaluate active faulting, slope instability, thaw settlement, erosion, and other engineering constraints along proposed pipeline routes, and (2) provide a base layer for the state-federal GIS database that will be used to evaluate permit applications...
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...
In advance of design, permitting, and construction of a pipeline to deliver North Slope natural gas to out-of-state customers and Alaska communities, the Division of Geological & Geophysical Surveys (DGGS) has acquired LiDAR (Light Detection and Ranging) data along proposed pipeline routes, nearby areas of infrastructure, and regions where significant geologic hazards have been identified. LiDAR data will serve multiple purposes, but have primarily been collected to (1) evaluate active faulting, slope instability, thaw settlement, erosion, and other engineering constraints along proposed pipeline routes, and (2) provide a base layer for the state-federal GIS database that will be used to evaluate permit applications...
In advance of design, permitting, and construction of a pipeline to deliver North Slope natural gas to out-of-state customers and Alaska communities, the Division of Geological & Geophysical Surveys (DGGS) has acquired LiDAR (Light Detection and Ranging) data along proposed pipeline routes, nearby areas of infrastructure, and regions where significant geologic hazards have been identified. LiDAR data will serve multiple purposes, but have primarily been collected to (1) evaluate active faulting, slope instability, thaw settlement, erosion, and other engineering constraints along proposed pipeline routes, and (2) provide a base layer for the state-federal GIS database that will be used to evaluate permit applications...
Aerial photographs of the coastline from Teller to Nome were collected between August 26, 2015 - August 27, 2015. The photographs were processed using Structure-from-Motion (SfM) photogrammetric techniques. Global Positioning System (GPS) checkpoints were collected via a Global Navigation Satellite System (GNSS) survey conducted between August 15 and September 14, 2015. For the purposes of open access to elevation and orthoimagery datasets in coastal regions of Alaska, this collection is being released as a Raw Data File with an open end-user license. Orthoimages contain 4-band, 8-bit, unsigned raster data (red/green/blue/no data; file format-GeoTIFF; source-Fairbanks Fodar) with 20 cm GSD. No-data values are found...
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...
The State of Alaska Division of Geological & Geophysical Surveys (DGGS) produced an orthorectified aerial optical image mosaic (orthoimage) and digital surface model over an area extending from milepost (MP) 17 to approximately MP 24.5 on the Alaska State Highway 7 (Haines Highway) north of Haines along the Chilkat River in southeast Alaska. The aerial photogrammetric survey targeted large debris fans and their alpine source areas on the west side of the Takshanuk Mountains in support of cryosphere hazards mapping and monitoring efforts. Aerial photographs and Global Navigation Satellite System (GNSS) data were collected on May 26, 2014, and were processed using Structure-from-Motion (SfM) photogrammetric techniques...
In advance of design, permitting, and construction of a pipeline to deliver North Slope natural gas to out-of-state customers and Alaska communities, the Division of Geological & Geophysical Surveys (DGGS) has acquired LiDAR (Light Detection and Ranging) data along proposed pipeline routes, nearby areas of infrastructure, and regions where significant geologic hazards have been identified. LiDAR data will serve multiple purposes, but have primarily been collected to (1) evaluate active faulting, slope instability, thaw settlement, erosion, and other engineering constraints along proposed pipeline routes, and (2) provide a base layer for the state-federal GIS database that will be used to evaluate permit applications...
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...
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...
Photogrammetric digital surface models and orthoimagery for 26 coastal communities of western Alaska
The State of Alaska Division of Geological & Geophysical Surveys acquired photogrammetric digital surface models (DSMs) and co-registered orthorectified aerial images (orthoimages) for the west coast of Alaska in support of coastal vulnerability mapping efforts. This report is a summary of the data collected over 26 developed areas along approximately 3,500 km of coastline in the Bering Sea, Norton Sound, and Yukon-Kuskokwim Delta regions (fig. 1). Aerial photographs were collected between July 31 and September 6, 2015, and processed using Structure from- Motion (SfM) photogrammetry techniques. Ground control points (GCPs) and checkpoints were collected in support of these data products during a Global Navigation...
|
|
