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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...
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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...
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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...
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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...
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In this report, we evaluate potential tsunami hazards for southeastern Alaska communities of Elfin Cove, Gustavus, and Hoonah and numerically model the extent of inundation from tsunami waves generated by tectonic and landslide sources. We perform numerical modeling of historic tsunami events, such as the tsunami triggered by the 1964 Great Alaska Earthquake, and the tsunami waves generated by the recent 2011 Tohoku and 2012 Haida Gwaii earthquakes. Hypothetical tsunami scenarios include variations of the extended 1964 rupture, megathrust earthquakes in the Prince William Sound and Alaska Peninsula regions, and a Cascadia megathrust earthquake. Local underwater landslide events in Taylor Bay and Port Frederick,...
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We evaluate potential tsunami hazards for the city of Valdez and numerically model the extent of inundation from tsunamis generated by earthquake and landslide sources. Tsunami scenarios include a repeat of the tsunami triggered by the 1964 Great Alaska Earthquake, as well as hypothetical tsunamis generated by an extended 1964 rupture, a Cascadia megathrust earthquake, and earthquakes from the Prince William Sound and Kodiak asperities of the 1964 rupture. Local underwater landslide events in Port Valdez are also considered as credible tsunamigenic scenarios. Results of numerical modeling are verified by simulating the tectonic and landslide-generated tsunamis in Port Valdez observed during the 1964 earthquake....
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This 1:50,000 scale geologic map describes the distribution of unconsolidated deposits, identifies local geologic hazards, and provides information about the depositional environment and basic engineering properties of common surficial-geologic materials in and around Shaktoolik, Alaska. Map units are the result of combined field observations and aerial imagery interpretation. A suite of local ground observations were collected over a two-week period in July 2011 by a helicopter-supported team of DGGS geologists and collaborators. Field investigations included soil test pits, sample collection, soil and rock description, oblique aerial photography, and documentation of landscape morphology.
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Potential tsunami hazards for the community of Chenega Bay, located on Evans Island between Sawmill and Crab bays, were evaluated by numerically modeling the extent of inundation from tsunami waves generated by earthquakes. Tsunami scenarios include a repeat of the tsunami triggered by the 1964 Great Alaska Earthquake, as well as tsunamis generated by a hypothetically extended 1964 rupture, a hypothetical Cascadia megathrust earthquake, a hypothetical earthquake in the Kodiak asperity of the 1964 rupture, and a hypothetical Tohoku-type rupture in the Gulf of Alaska region. Results of numerical modeling are verified by simulations of the tectonic tsunami observed in Chenega Cove during the 1964 earthquake. The results...
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The purpose of this study was to evaluate a potential tsunami risk for communities of Homer and Seldovia in the Kachemak Bay area, Alaska. This report provides guidance to the local emergency managers in tsunami hazard assessment. We used a numerical modeling method to estimate the extent of inundation due to tsunami waves generated by earthquake sources. Our tsunami scenarios included a repeat of the tsunami of the 1964 great Alaska earthquake, as well as a hypothetical tsunami wave generated by a local fault source. We didn't consider landslide-generated tsunamis in this study. Results of numerical modeling combined with historical observations in the region are intended to help local emergency services officials...
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In this report, we evaluate potential tsunami hazards for the southeastern Alaska community of Juneau and numerically model the extent of inundation from tsunami waves generated by tectonic and submarine landslide sources. We calibrate our tsunami model by numerically simulating the 2011 Tohoku tsunami at Juneau and comparing our results to instrument records. Analysis of calculated and observed water level dynamics for the 2011 event in Juneau reveals that the model underestimates the observed wave heights in the city by a factor of two, likely due to complex tsunami-tide interactions. We compensate for this numerical underestimation by doubling the coseismic slip of the hypothetical tsunami sources in our models....
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The purpose of this study is to evaluate potential tsunami hazards for the community of Whittier and western Passage Canal area. We numerically model the extent of inundation due to tsunami waves generated from earthquake and landslide sources. Tsunami scenarios include a repeat of the tsunami triggered by the 1964 Great Alaska Earthquake, as well as tsunami waves generated by a hypothetically extended 1964 rupture, a hypothetical Cascadia megathrust earthquake, hypothetical earthquakes in Prince William Sound, and Kodiak asperities of the 1964 rupture. Local underwater landslide and rockslide events in Passage Canal are also considered as credible tsunamigenic scenarios. Results of numerical modeling combined with...
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The purpose of this study is to evaluate potential tsunami hazards for the community of Sitka. We numerically modeled the extent of inundation from tsunami waves generated by near- and far-field tectonic sources. We performed numerical modeling of historic events at Sitka, such as the tsunami triggered by the 1964 Great Alaska Earthquake, and the tsunami waves generated by the recent 2011 Tohoku and 2012 Haida Gwaii earthquakes. Hypothetical tsunami scenarios include variations of the extended 1964 rupture, megathrust earthquakes in the Alaska Peninsula region and in the Cascadia subduction zone, and a thrust earthquake in the region of the Queen Charlotte-Fairweather fault zone. Results of numerical modeling combined...
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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...
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Staff from Alaska Earthquake Center, Geophysical Institute and Alaska Division of Geological & Geophysical Surveys evaluated potential potential tsunami hazard for the communities of Kodiak, Womens Bay, and for the U.S. Coast Guard base on Kodiak Island 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 Alaska-Aleutian megathrust. The worst-case scenarios for the Kodiak communities are thought to be the subduction zone earthquakes offshore Kodiak Island with their greatest slip at 5-35 km (3.1-22...
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On November 8, 2011, an extra-tropical cyclone with a low pressure of 945 millibars developed over the Bering Sea and moved northeast across the western coast of Alaska. This large storm brought high winds (gusts of up to 85 mph) to the entire region and a storm surge of approximately 3 meters to parts of Norton Sound. The storm caused extensive flooding in the lower portion of Golovin on the afternoon of November 9, 2011. A team of Alaska Division of Geological & Geophysical Surveys (DGGS) scientists visited Golovin on November 15, 2011, to document peak water levels, runup elevations, and inundation extents caused by this event. These data were combined with photographs taken by local residents during the event...
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The purpose of this study is to evaluate potential tsunami hazards for the Prince William Sound communities of Cordova and Tatitlek. We numerically model the extent of inundation from tsunami waves generated by earthquake sources and consider the results in light of historical observations. Tsunami scenarios include a repeat of the tsunami triggered by the 1964 Great Alaska Earthquake as well as tsunami waves generated by the following hypothetical scenarios: An extended 1964 rupture, a Cascadia megathrust earthquake, various earthquakes in Prince William Sound, and a Tohoku-type earthquake in the Gulf of Alaska region. Results of our numerical modeling, combined with historical observations, are designed to provide...
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Potential tsunami hazard for the Alaska Peninsula communities of Chignik and Chignik Lagoon 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 Alaska-Aleutian megathrust. The worst-case scenarios for Chignik area communities are thought to be thrust earthquakes along the Alaska Peninsula with their greatest slip at 5-35 km (3.1-22 mi) depth. We also consider Tohoku-type ruptures and an outer-rise rupture along the Alaska Peninsula. The maximum predicted water depth on Anderson Street...
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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...
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This derivative engineering-geologic map illustrates potential near-surface sources of various geologic materials that may be useful for construction near the Dalton Highway area, from Atigun Gorge to Slope Mountain. The map area is located in the west-central Philip Smith Mountains quadrangle. The map extends from the northern flank of the Endicott Mountains into the Arctic Foothills province. Field observations indicate that each geologic unit (for example, stream alluvium) has a definite composition or range of composition. Therefore, the probable presence of materials is interpreted from the distribution of geologic units on the geologic map of this quadrangle. Map unit descriptions also include discussion of...


    map background search result map search result map Engineering-geologic map of the Dalton Highway from Galbraith Lake to Slope Mountain, southern Arctic Foothills, Alaska Tsunami hazard maps of the Homer and Seldovia areas, Alaska Tsunami inundation maps of Seward and northern Resurrection Bay, Alaska Tsunami inundation maps of Whittier and western Passage Canal, Alaska Coastal hazard field investigations in response to the November 2011 Bering Sea storm, Norton Sound, Alaska Tsunami inundation maps of Port Valdez, Alaska Tsunami inundation maps of Sitka, Alaska Tsunami inundation maps of Cordova and Tatitlek, Alaska Tsunami inundation maps of the villages of Chenega Bay and northern Sawmill Bay, Alaska Preliminary volcano-hazard assessment for Fisher volcano, Unimak Island, Alaska Tsunami inundation maps of Elfin Cove, Gustavus, and Hoonah, Alaska Tsunami inundation maps of Fox Islands communities, including Dutch Harbor and Akutan, Alaska Tsunami inundation maps for King Cove and Cold Bay communities, Alaska Tsunami inundation map for the village of Nikolski, Alaska Tsunami inundation maps for the communities of Chignik and Chignik Lagoon, Alaska Tsunami inundation maps for the city of Sand Point, Alaska Surficial geologic map of the Shaktoolik area, Norton Bay Quadrangle, Alaska Updated tsunami inundation maps of the Kodiak area, Alaska Tsunami inundation maps for Juneau, Alaska Coastal hazard field investigations in response to the November 2011 Bering Sea storm, Norton Sound, Alaska Tsunami inundation maps of Whittier and western Passage Canal, Alaska Tsunami inundation maps of the villages of Chenega Bay and northern Sawmill Bay, Alaska Tsunami inundation map for the village of Nikolski, Alaska Tsunami inundation maps of Sitka, Alaska Tsunami inundation maps of Port Valdez, Alaska Updated tsunami inundation maps of the Kodiak area, Alaska Tsunami hazard maps of the Homer and Seldovia areas, Alaska Tsunami inundation maps for King Cove and Cold Bay communities, Alaska Engineering-geologic map of the Dalton Highway from Galbraith Lake to Slope Mountain, southern Arctic Foothills, Alaska Tsunami inundation maps of Fox Islands communities, including Dutch Harbor and Akutan, Alaska Tsunami inundation maps of Elfin Cove, Gustavus, and Hoonah, Alaska Tsunami inundation maps for Juneau, Alaska Tsunami inundation maps of Cordova and Tatitlek, Alaska Surficial geologic map of the Shaktoolik area, Norton Bay Quadrangle, Alaska Preliminary volcano-hazard assessment for Fisher volcano, Unimak Island, Alaska