Identification_Information: Citation: Citation_Information: Originator: Suleimani, E.N. Originator: Nicolsky, D.J. Originator: Koehler, R.D. Publication_Date: 2015 Title: Tsunami inundation maps of Elfin Cove, Gustavus, and Hoonah, Alaska Geospatial_Data_Presentation_Form: report and digital data Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2015-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 79 p. Online_Linkage: http://dx.doi.org/10.14509/29404 Description: Abstract: 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, and a rockslide in Tidal Inlet are also considered as possible tsunamigenic scenarios. Numerical modeling results, combined with historical observations in the region, are intended to provide guidance to local emergency management in tsunami hazard assessment, evacuation planning, and public education for the reduction of future tsunami risk. Purpose: The presented results presented are intended to provide guidance to local emergency management agencies in tsunami-hazard assessment, evacuation planning, and public education, to reduce damages from future tsunami hazards. Supplemental_Information: >border: Outline of the study area. >max-inundation-line: Estimated, "maximum credible scenario" inundation line that encompasses the maximum extent of flooding based on model simulation of all credible source scenarios and historical observations. The "maximum credible scenario" inundation line becomes a basis for local tsunami hazard planning and development of evacuation maps. >max-flow-depth: Raster images depicting maximum composite flow depths over dry land. Pixel values provide the modeled depth (in meters) of maximum inundation. For each grid point, the pixel value provides the modeled depth of water (in meters) over previously dry land, representing the maximum depth value of all calculated tsunami scenarios. >coastline: Digitized MHHW (Mean Higher High Water) coastline of each community. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 2013 Ending_Date: 2015 Currentness_Reference: ground condition Status: Progress: complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -136.422607 East_Bounding_Coordinate: -135.392487 North_Bounding_Coordinate: 58.474888 South_Bounding_Coordinate: 58.083485 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Theme_Keyword: Active Fault Theme_Keyword: Coastal Theme_Keyword: Coastal and River Theme_Keyword: Earthquake Theme_Keyword: Earthquake Related Slope Failure Theme_Keyword: Emergency Preparedness Theme_Keyword: Engineering Theme_Keyword: Engineering Geology Theme_Keyword: Fault Displacement Theme_Keyword: Faulting Theme_Keyword: Flood Theme_Keyword: Geologic Hazards Theme_Keyword: Geology Theme_Keyword: Hazards Theme_Keyword: Inundation Theme_Keyword: Landslide Theme_Keyword: Modeling Theme_Keyword: Raster Image Theme_Keyword: Rock Avalanche Theme_Keyword: Rockfall Theme_Keyword: Seismic Hazards Theme_Keyword: Slides Theme_Keyword: Slope Theme_Keyword: Slope Instability Theme_Keyword: Tides Theme_Keyword: Topography Theme_Keyword: Tsunami Place: Place_Keyword_Thesaurus: Alaska Division of Geological & Geophysical Surveys Place_Keyword: Bartlett Cove Place_Keyword: Humpback Creek Place_Keyword: Icy Strait Place_Keyword: Port Frederick Place_Keyword: Southeast Alaska Place_Keyword: Taylor Bay Place_Keyword: Tidal Inlet Temporal: Temporal_Keyword_Thesaurus: Walker, J.D., Geissman, J.W., Bowring, S.A, and Babcock, L.E., comp., 2012, Geologic Time Scale v. 4.0: Geological Society of America Temporal_Keyword: Holocene Access_Constraints: This report, map, and/or dataset is available directly from the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys (see contact information below). Use_Constraints: This dataset includes results of numerical modeling of earthquake-generated tsunami waves for a specific community. Modeling was completed using the best information and tsunami modeling software available at the time of analysis. They are numerical solutions and, while they are believed to be accurate, their ultimate accuracy during an actual tsunami will depend on the specifics of earth deformations, on-land construction, tide level, and other parameters at the time of the tsunami. Actual areas of inundation may differ from areas shown in this dataset. Landslide tsunami sources may not be included in the modeling due to unknown potential impact of such events on a given community; please refer to accompanying report for more information on tsunami sources used for this study. The limits of inundation shown should only be used as a general guideline for emergency planning and response action in the event of a major tsunamigenic earthquake. These results are not intended for any other use, including land-use regulation or actuarial purposes. Any hard copies or published datasets utilizing these datasets shall clearly indicate their source. If the user has modified the data in any way, the user is obligated to describe the types of modifications the user has made. The user specifically agrees not to misrepresent these datasets, nor to imply that changes made by the user were approved by the State of Alaska, Department of Natural Resources, Division of Geological & Geophysical Surveys. The State of Alaska makes no express or implied warranties (including warranties for merchantability and fitness) with respect to the character, functions, or capabilities of the electronic data or products or their appropriateness for any user's purposes. In no event will the State of Alaska be liable for any incidental, indirect, special, consequential, or other damages suffered by the user or any other person or entity whether from the use of the electronic services or products or any failure thereof or otherwise. In no event will the State of Alaska's liability to the Requestor or anyone else exceed the fee paid for the electronic service or product. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Position: GIS Manager Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Electronic_Mail_Address: dggsgis@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Data_Set_Credit: This project was supported by the National Oceanic and Atmospheric Administration (NOAA) under Reimbursable Service Agreement ADN 0931000 with the State of Alaska's Division of Homeland Security and Emergency Management. Some of the research in this publication is sponsored by the Cooperative Institute for Alaska Research with funds from NOAA under cooperative agreement NA08OAR4320751 with the University of Alaska. Numerical calculations for this work were supported by a grant of High Performance Computing (HPC) resources from the Arctic Region Supercomputing Center (ARSC) at the University of Alaska Fairbanks. We thank Chris Waythomas and Isaac Fine for their reviews that improved the report and maps. Cross_Reference: Citation_Information: Originator: Nicolsky, D.J. Originator: Suleimani, E.N. Originator: Combellick, R.A. Originator: Hansen, R.A. Publication_Date: 2011 Title: Tsunami inundation maps of Whittier and western Passage Canal, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2011-7 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 65 p Online_Linkage: http://dx.doi.org/10.14509/23244 Cross_Reference: Citation_Information: Originator: Nicolsky, D.J. Originator: Suleimani, E.N. Originator: Haeussler, P.J. Originator: Ryan, H.F. Originator: Koehler, R.D. Originator: Combellick, R.A. Originator: Hansen, R.A. Publication_Date: 2013 Title: Tsunami inundation maps of Port Valdez, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2013-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 77 p., 1 sheet, scale 1:12,500 Online_Linkage: http://dx.doi.org/10.14509/25055 Cross_Reference: Citation_Information: Originator: Nicolsky, D.J. Originator: Suleimani, E.N. Originator: Koehler, R.D. Publication_Date: 2014 Title: Tsunami inundation maps of Cordova and Tatitlek, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2014-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 49 p Online_Linkage: http://dx.doi.org/10.14509/27241 Cross_Reference: Citation_Information: Originator: Nicolsky, D.J. Originator: Suleimani, E.N. Originator: Koehler, R.D. Publication_Date: 2014 Title: Tsunami inundation maps of the villages of Chenega Bay and northern Sawmill Bay, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2014-3 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 50 p Online_Linkage: http://dx.doi.org/10.14509/29126 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Combellick, R.A. Originator: Marriott, D. Originator: Hansen, R.A. Originator: Venturato, A.J. Originator: Newman, J.C. Publication_Date: 2005 Title: Tsunami hazard maps of the Homer and Seldovia areas, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2005-2 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 28 p., 2 sheets, scale 1:12,500 Online_Linkage: http://dx.doi.org/10.14509/14474 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Hansen, R.A. Originator: Combellick, R.A. Originator: Carver, G.A. Publication_Date: 2002 Title: Tsunami hazard maps of the Kodiak area, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2002-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 16 p., 4 sheets, scale 1:12,500 Online_Linkage: http://dx.doi.org/10.14509/2860 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Nicolsky, D.J. Originator: West, D.A. Originator: Combellick, R.A. Originator: Hansen, R.A. Publication_Date: 2010 Title: Tsunami inundation maps of Seward and northern Resurrection Bay, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2010-1 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 47 p., 3 sheets, scale 1:12,500 Online_Linkage: http://dx.doi.org/10.14509/21001 Cross_Reference: Citation_Information: Originator: Suleimani, E.N. Originator: Nicolsky, D.J. Originator: Koehler, R.D. Publication_Date: 2013 Title: Tsunami inundation maps of Sitka, Alaska Series_Information: Series_Name: Report of Investigation Issue_Identification: RI 2013-3 Publication_Information: Publication_Place: Fairbanks, Alaska, United States Publisher: Alaska Division of Geological & Geophysical Surveys Other_Citation_Details: 76 p., 1 sheet, scale 1:250,000 Online_Linkage: http://dx.doi.org/10.14509/26671 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The maps showing the results of our modeling have been completed using the best information available and are believed to be accurate, however, their preparation required many assumptions. We described several scenarios and provide an estimate of maximum credible tsunami inundation. Actual conditions during a tsunami event may vary from those considered, so the accuracy cannot be guaranteed. The limits of inundation shown should be used only as a guideline for emergency planning and response action. Actual areas inundated will depend on specifics of the earth deformations, on-land construction, and tide level, and they may differ from areas shown on the map. The information on this map is intended to provide a basis for state and local agencies to plan emergency evacuation and tsunami response actions in the event of a major tsunamigenic earthquake. These results are not intended for land-use regulation or building-code development. This DGGS Report of Investigations is a final report of scientific research. It has received technical review by several scientists familiar with the subject matter. Uncertainties associated with the depiction or interpretation of various features are discussed in the manuscript. Logical_Consistency_Report: Model validation for this report included comparison of the modeled results to observations that were recorded during historic events. Completeness_Report: Southeast Alaska has a long record of tsunami waves generated by submarine and subaerial landslides, avalanches, and rockfalls. We consider several hypothetical slope failure scenarios that could generate waves that could be potentially hazardous to the communities of Elfin Cove, Gustavus, and Hoonah. Unfortunately, there is no geotechnical information to constrain the locations and thicknesses of these potential underwater slides. Uncertainties are associated with geometry and configuration of potential landslides and rockfalls. Parameters of the hypothetical slides are listed in table 3 (of the manuscript) and discussed in more detail. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: The hydrodynamic model used to calculate propagation and runup of tsunami waves is a nonlinear, flux-formulated, shallow-water model. It passes the validation and verification tests required for models used in production of tsunami inundation maps. The source mechanism remains the biggest unknown in the problem of tsunami modeling. Since the initial condition for the modeling is determined by the displacement of the ocean bottom, the largest source of error is the earthquake model. When the tsunami is generated in the vicinity of the coast, the direction of the incoming waves, their amplitudes and times of arrival are determined by the initial displacements of the ocean surface in the source area because the distance to the shore is too small for the waves to dissipate. Therefore, the near-field inundation modeling results are especially sensitive to the fine structure of the tsunami source. The modeling process is highly sensitive to errors when the complexity of the source function is combined with its proximity to the coastal zone. The horizontal resolution of the grid used for inundation modeling is about 15 m (49 ft). This scale is limited by the resolution of the topographic and bathymetric data used for the grid construction. The 15 m (49 ft) resolution is high enough to describe major relief features; however, small topographic features, buildings, and other facilities cannot be accurately resolved by the existing model. More information about modeling uncertainties can be found in the accompanying report. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The vertical accuracy of the inundation modeling is dependent on the accuracy and resolution of the digital elevation models (DEMs) and tidal datum values that were used to compile the computational grid. Prior to scenario modeling, bathymetric data were shifted to use Mean Higher High Water (MHHW) as the vertical datum. The depths of inundation shown should be used only as a guideline for emergency planning and response action. Actual inundation water depth will depend on specifics of the earth deformations, on-land construction, and tide level, and they may differ from areas shown by this data. The information is intended to permit state and local agencies to plan emergency evacuation and tsunami response actions in the event of a major tsunamigenic earthquake. These results are not intended for land-use regulation or building-code development. For additional information please reference the Grid Development and Data Sources section of the associated manuscript. Lineage: Process_Step: Process_Description: Development of nested grids - To support inundation modeling of coastal areas in Alaska, we used a series of nested telescoping grids, or digital elevation models (DEMs), as input layers for tsunami inundation modeling and mapping. These grids of increasing resolution allowed us to propagate waves generated by various tectonic and landslide tsunami sources to Elfin Cove, Gustavus, and Hoonah. In order to propagate a wave from its source to various coastal locations we used embedded grids, placing a large, coarse grid in deep water and coupling it with smaller, finer grids in shallow water areas. The bathymetric and topographic relief in each nested grid is based on digital elevation models (DEMs) developed at the National Geophysical Data Center (NGDC) of the National Oceanic Atmospheric Administration (NOAA), in Boulder, Colorado. The extent of each grid used for our tsunami inundation mapping is listed in Table 1 of the accompanying report. To provide greater DEM accuracy near the shorelines, we augmented the topographic datasets with RTK - GPS survey measurements. Survey measurements were converted to MHHW datum using methods described within the associated report. See Methodology and Data section of the accompanying report for more detail and additional grid development source information. Process_Date: 2014 Process_Step: Process_Description: Model validation - The numerical model that we used for simulation of tsunami wave propagation and runup was validated through a set of analytical benchmarks and tested against laboratory data. The model solves nonlinear shallow water equations using a finite-difference method on a staggered grid. See Methodology and Data section of the accompanying report for more detail and additional model information. Process_Date: 2014 Process_Step: Process_Description: Model verification - We verified the numerical model by comparing results of the inundation modeling with observations collected from the Tohoku 2011 and Haida Gwaii 2012 tsunamis. First, we simulated the tectonic tsunami in Elfin Cove, Gustavus, and Hoonah using an output of a coseismic deformation model of each of the earthquake as an initial condition for water waves. Then we compared the modeled time series with the tsunami wave history recorded by the Elfin Cove tide gauge. See Methodology and Data and Modeling Results sections of the accompanying report for more detail and additional model information. Process_Date: 2014 Process_Step: Process_Description: Numerical simulations of hypothetical tsunami scenarios - We assessed hazard related to tectonic tsunamis in Elfin Cove, Gustavus, and Hoonah by performing model simulations for each hypothetical source scenario. Numerical results for each scenario include extent of inundation, sea level and velocity time series calculations, and tsunami flow depth. See Modeling Results section of the accompanying report for more detail and additional information. Process_Date: 2014 Process_Step: Process_Description: Compilation of maximum inundation zone and maximum flow depths - We calculated maximum composite extent of inundation by combining the maximum calculated inundation extents of all scenarios. The same method was used for calculation of maximum flow depths over dry land. See Modeling results section of the accompanying report for more detail and additional information. Process_Date: 2014 Process_Step: Process_Description: Calculation of the potential inundation lines - For each grid cell in the high-resolution DEMs Elfin Cove, Gustavus, and Hoonah, we determined whether the cell was inundated by waves or stayed dry throughout the entire simulation. Then, we defined a function such that it is equal to one at the center of each wet cell and is negative one at the center of each dry cell. Using a linear interpolation algorithm in Matlab, we plotted a zero-value contour that delineates dry and wet cells from each other. The resultant contour line (or a collection of lines if the contour is not a simply connected) was directly exported to the ArcGIS using WGS84 datum. Process_Date: 2014 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.000001 Longitude_Resolution: 0.000001 Geographic_Coordinate_Units: decimal degrees Geodetic_Model: Horizontal_Datum_Name: World Geodetic System of 1984 Ellipsoid_Name: WGS 84 Semi-major_Axis: 6378137 Denominator_of_Flattening_Ratio: 298.257223563 Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: Mean Higher High Water Depth_Resolution: 100 Depth_Distance_Units: centimeters Depth_Encoding_Method: Attribute values Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Attribute_Layer_Name: border Entity_Type_Label: ri2015-1-border.shp Entity_Type_Definition: Outline of the study area. File format: shapefile Entity_Type_Definition_Source: Alaska Division of Geological & Geophysical Surveys (DGGS) and Alaska Earthquake Center, Geophysical Institute, University of Alaska Detailed_Description: Entity_Type: Entity_Attribute_Layer_Name: max-inundation-line Entity_Type_Label: ri2015-1-max-inundation-line-elfincove.shp, ri2015-1-max-inundation-line-gustavus.shp ri2015-1-max-inundation-line-hoonah.shp Entity_Type_Definition: Estimated, "maximum credible scenario" inundation line that encompasses the maximum extent of flooding based on model simulation of all credible source scenarios and historical observations. The "maximum credible scenario" inundation line becomes a basis for local tsunami hazard planning and development of evacuation maps. File format: shapefile Entity_Type_Definition_Source: Alaska Earthquake Center, Geophysical Institute, University of Alaska, this report Detailed_Description: Entity_Type: Entity_Attribute_Layer_Name: max-flow-depth Entity_Type_Label: ri2015-1-max-flow-depth-elfincove.tif, ri2015-1-max-flow-depth-gustavus.tif ri2015-1-max-flow-depth-hoonah.tif Entity_Type_Definition: Raster images depicting maximum composite flow depths over dry land. Pixel values provide the modeled depth (in meters) of maximum inundation. For each grid point, the pixel value provides the modeled depth of water (in meters) over previously dry land, representing the maximum depth value of all calculated tsunami scenarios. File format: GeoTIFF Entity_Type_Definition_Source: Alaska Earthquake Center, Geophysical Institute, University of Alaska, this report Detailed_Description: Entity_Type: Entity_Attribute_Layer_Name: coastline Entity_Type_Label: ri2015-1-coastline-elfincove.shp, ri2015-1-coastline-gustavus.shp ri2015-1-coastline-hoonah.shp Entity_Type_Definition: Digitized MHHW (Mean Higher High Water) coastline of each community. File format: shapefile Entity_Type_Definition_Source: Alaska Earthquake Center, Geophysical Institute, University of Alaska, this report Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: Alaska Division of Geological & Geophysical Surveys Contact_Address: Address_Type: mailing and physical Address: 3354 College Road City: Fairbanks State_or_Province: AK Postal_Code: 99709-3707 Country: USA Contact_Voice_Telephone: (907)451-5020 Contact_Facsimile_Telephone: (907)451-5050 Contact_Electronic_Mail_Address: dggspubs@alaska.gov Hours_of_Service: 8 am to 4:30 pm, Monday through Friday, except State holidays Contact_Instructions: Please view our website (http://www.dggs.alaska.gov) for the latest information on available data. Please contact us using the e-mail address provided above when possible. 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