Metadata: Identification_Information: Citation: Citation_Information: Originator: Drake M. Singleton Originator: Daniel S. Brothers Originator: Jenna C. Hill Originator: Peter J. Haeussler Originator: Robert C. Witter Publication_Date: 20230706 Title: Chirp seismic-reflection and navigation data collected in Alaskan lakes and fjords following the 2018 Anchorage earthquake Geospatial_Data_Presentation_Form: seismic-reflection data in SEG-Y format and navigation polylines in shapefile format Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P924775B Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, California Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P924775B Larger_Work_Citation: Citation_Information: Originator: Drake M. Singleton Originator: Daniel S. Brothers Originator: Jenna C. Hill Originator: Peter J. Haeussler Originator: Robert C. Witter Publication_Date: 2023 Title: Geophysical and core sample data collected in lakes and fjords of southcentral Alaska following the 2018 Anchorage earthquake Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P924775B Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Other_Citation_Details: Suggested Citation: Singleton, D.M., Brothers, D.S., Hill, J.C., Haeussler, P.J., and Witter, R.C., 2023, Geophysical and core sample data collected in lakes and fjords of southcentral Alaska following the 2018 Anchorage earthquake: U.S. Geological Survey data release, https://doi.org/10.5066/P924775B. Online_Linkage: https://doi.org/10.5066/P924775B Description: Abstract: Chirp seismic-reflection data and associated navigation files were collected from lacustrine and fjord basins in southcentral Alaska following the 2018 Anchorage earthquake. These data were collected from a 25-foot Boston Whaler (R/V Moose Dancer),18-foot cataraft (R/V Enterprise), and the R/V Alaskan Gyre in the summers of 2020 and 2021 for use in regional hazard assessments relating to Alaska’s seismic hazards. Purpose: Identification of fault-related submarine hazards is a primary mission of the USGS Coastal and Marine Hazards and Resources Program. Intraslab earthquakes, which occur at depth within the subducting plate, can cause intense shaking at the Earth’s surface, but do not cause surficial faulting or result in significant land level changes. The seismic shaking associated with intraslab earthquakes can remobilize subaqueous sediment and lead to gravity driven sediment flows, potentially creating a record of past shaking from these events. To gain a better understanding of the conditions that produce seismically triggered deposits in subaqueous basins the USGS collected Chirp seismic and sediment cores from several lakes and fjords following the M7.1 2018 Anchorage earthquake. These data are intended to further our understand of geologic hazard in southcentral Alaska, improve risk assessments for local communities and critical infrastructure, and to provide data for future research on regional paleoseismic records in southcentral Alaska. Supplemental_Information: Additional information about the field activities from which these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=2021-612-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2020-615-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2020-625-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form, as well as in Esri format, this metadata file may include some Esri-specific terminology. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20200808 Ending_Date: 20210622 Currentness_Reference: Ground conditions at time data were collected Status: Progress: In work Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -151.490850 East_Bounding_Coordinate: -148.537050 North_Bounding_Coordinate: 62.520180 South_Bounding_Coordinate: 60.071108 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:19a6dc80-2f35-439b-a52a-87f32de63f5b Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: inlandWaters Theme_Keyword: oceans Theme_Keyword: geoscientificInformation Theme_Keyword: location Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: substrate Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: marine geophysics Theme_Keyword: sub-bottom profiling Theme_Keyword: geospatial datasets Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: data processing Theme_Keyword: seismic reflection profiling Theme_Keyword: Global Positioning System observations Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: Pacific Coastal and Marine Science Center Theme_Keyword: PCMSC Theme_Keyword: seismic reflection Place: Place_Keyword_Thesaurus: Geographic Names Information System Place_Keyword: Pacific Ocean Place_Keyword: Prince William Sound Place_Keyword: Passage Canal Place_Keyword: State of Alaska Place_Keyword: Skilak Lake Place_Keyword: Kenai Lake Place_Keyword: Tustumena Lake Place_Keyword: Chelatna Lake Access_Constraints: None Use_Constraints: USGS-authored or produced data and information are in the public domain from the U.S. Government and are freely redistributable with proper metadata and source attribution. Please recognize and acknowledge the U.S. Geological Survey as the originator(s) of the dataset and in products derived from these data. This information is not intended for navigation purposes. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Person: PCMSC Science Data Coordinator Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Data_Set_Credit: USGS PCMSC Marine Facility personnel Rachel Marcuson assisted with Chirp seismic data acquisition. Native_Data_Set_Environment: Field seismic data were collected with EdgeTech Discover acquisition software and processed using SioSeis (V 2022.1.2) on a MacOS operating system. Seismic tracklines were processed using ArcGIS Pro (v. 2.9.1) on a Windows 10 operating system. Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Quality control of attribute accuracy was conducted during field data collection and processing workflows. Logical_Consistency_Report: All SEG-Y and navigation data were derived from the same instruments and processing workflows. Paired navigation and SEG-Y files have corresponding filenames and/or corresponding names indicated in shapefile attribute fields. Completeness_Report: Profiles Kel20-04 and Kel20-06 collected during 2020-625-FA experienced power loss in the tow-fish data cable resulting in loss of recorded data for a short period of time. Users are advised to read the rest of the metadata record carefully for additional details. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: A Hemisphere V110 GPS system was used for obtaining navigation data during the cruise with a stated accuracy of 0.6 meters (95 percent confidence). Horizontal position coordinates in WGS 84/UTM zone 6N reference frame are located in index position 73-80 within the segy header. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Two-way travel time in milliseconds referenced to sea level is provided in the SEG-Y files. Referencing two-way travel time to sea level is accomplished via an internal pressure logger within the Chirp towfish with a stated accuracy of approximately 0.001 psi which is converted to water depth accurate to within approximately 1 cm. If this depth information is recorded, it is populated in the receiver group elevation header in the SEG-Y files (bytes 41-44). Data collected during Field Activity 2021-612-FA does not record internal pressure logger information, but instead was collected from fixed pole position at a water depth of 60 centimeters. Lineage: Process_Step: Process_Description: Field seismic data collection 2020-625-FA: Seismic data were collected onboard the R/V Moose Dancer using an EdgeTech SB-424 Chirp sub-bottom profiler. Field data were collected in JSF format. Navigation data were collected simultaneously with a Hemisphere V110 GPS and saved into the seismic headers during acquisition. Profiles Kel20-04 and Kel20-06 collected during 2020-625-FA experienced power loss in the tow-fish data cable resulting in loss of recorded data for a short period of time. Process_Date: 20200808 Process_Step: Process_Description: Field seismic data collection 2020-615-FA: Seismic data were collected onboard the R/V Alaskan Gyre using an EdgeTech SB-516 Chirp sub-bottom profiler. Field data were collected in JSF format. Navigation data were collected simultaneously with a Hemisphere V110 GPS and saved into the seismic headers during acquisition. Process_Date: 20200912 Process_Step: Process_Description: Field seismic data collection 2021-612-FA: Seismic data were collected onboard the R/V Enterprise using an EdgeTech SB-216 Chirp sub-bottom profiler. Field data were collected in JSF format. Navigation data were collected simultaneously with a Hemisphere V110 GPS and saved into the seismic headers during acquisition. Process_Date: 20210612 Process_Step: Process_Description: The following processing flow was carried out in SioSeis (v. 2022.1.2) to process field data output to SEG-Y files: (1) Trace envelope data from field-collected JSF files were converted to SEG-Y format. Process_Date: 20220601 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Point Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Point Point_and_Vector_Object_Count: 39 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: WGS 1984 Ellipsoid_Name: WGS 84 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257224 Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: Local surface Depth_Resolution: 0.1 Depth_Distance_Units: meters Depth_Encoding_Method: Attribute values Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: 2021_612_2020_625_2020_615_chirp_nav.shp Entity_Type_Definition: Chirp seismic navigation in polyline format Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Sequential unique integers automatically generated Attribute: Attribute_Label: Shape Attribute_Definition: Feature Geometry Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: Feature shape automatically generated Attribute: Attribute_Label: Field1 Attribute_Definition: USGS Pacific Coastal and Marine Science Center (PCMSC) field activity identifier followed by line number. For Example, 2021-612_CH21_59 is line CH21_59 collected during field activity number 2021-612-FA. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: Unique seismic line number appended to field activity ID generated by the USGS Attribute: Attribute_Label: Length Attribute_Definition: Calculated length of the line in kilometers Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1.07490 Range_Domain_Maximum: 11.00757 Attribute_Units_of_Measure: kilometers Attribute_Measurement_Resolution: 0.00001 Overview_Description: Entity_and_Attribute_Overview: Zip archive of seismic shots with time stamp in standard SEG-Y format. Data for individual seismic lines follow file name format of Field-Activity-Number_LINE#.sgy. For example, 2021-612_CH21_59.sgy is line number CH21_59 collected during field activity 2021-612-FA. Entity_and_Attribute_Detail_Citation: Society of Exploration Geophysicists (SEG) Technical Standards, available for download at http://seg.org/Publications/SEG-Technical-Standards]. Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - CMGDS Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Resource_Description: Seismic data are available in SEG-Y format (2021-612_2020-625_2020-615_chirp.zip) with navigation provided in a shapefile format (2021-612_2020-625_2020-615_chirp.nav.zip) and accompanied by CSDGM FGDC-compliant metadata. Distribution_Liability: Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: SEG-Y Format_Version_Number: SEG-Y rev 1 Format_Information_Content: Zip file contains processed seismic data per single navigation line. Data for individual seismic lines follow file name format of Field-Activity-Number_LINE#.sgy. File_Decompression_Technique: Zip files may be decompressed with any zip utility (for example, 7zip, WinZip, Archive Utility). Transfer_Size: 4400 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P924775B Access_Instructions: Data can be downloaded using the Network_Resource_Name link and scrolling to the Seismic Data section. Fees: None. Technical_Prerequisites: Viewing SEG-Y data requires specialized software. A list of common SEG-Y processing and visualization software is available at http://www.oilfieldwiki.com/wiki/List_of_free_geophysics_software. Shapefile navigation data can be viewed using any Geographic Information System software (for example, ArcGIS, QGIS). Metadata_Reference_Information: Metadata_Date: 20230706 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, Pacific Coastal and Marine Science Center Contact_Person: PCMSC Science Data Coordinator Contact_Address: Address_Type: mailing and physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998