Metadata: Identification_Information: Citation: Citation_Information: Originator: James E. Conrad Originator: Jane A. Rudebusch Publication_Date: 20230808 Title: Methane seep locations derived from water-column acoustic backscatter data collected along Cascadia Margin offshore Oregon and Northern California, 2018-2021 Geospatial_Data_Presentation_Form: point shapefile Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9TW2X7Y Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, California Publisher: U.S. Geological Survey Other_Citation_Details: Suggested Citation: Conrad, J.E., and Rudebusch, J.A., 2023, Methane seep locations derived from water-column acoustic backscatter data collected along Cascadia margin offshore Oregon and Northern California, 2018-2021: USGS data release, https://doi.org/10.5066/P9TW2X7Y. Online_Linkage: https://doi.org/10.5066/P9TW2X7Y Description: Abstract: This dataset contains the locations of 902 methane cold seeps that were detected in acoustic water-column backscatter collected by the U.S. Geological Survey between 2018 to 2021. Rising bubbles emitting from methane seeps on the seafloor can be detected acoustically with multibeam echo sounding sonar used to collected seafloor bathymetric mapping data, which the USGS and NOAA have cooperatively collected along the Cascadia Margin offshore of northern California and Oregon for several years. Purpose: These data were collected from a multibeam echosounder survey as part of the broader effort by the USGS Marine Geohazards Program to compile high-resolution bathymetric maps of the Cascadia Margin. These data are used to characterize the seafloor geomorphology to help understand geologic hazards posed by the megathrust fault and other tectonic features of the Cascadia subduction zone. Multibeam echo sounding sonar used to map the depth and topography of the seafloor also captures anomalies in the water column above the seafloor, such as rising fluid bubbles that produce strong acoustic reflectance in the imaging sonar. Globally, vast reserves of methane are stored beneath the seafloor that can seep up into the water column and can be detected with multi-beam echo sounder. The seeps in this dataset were detected in the water-column acoustic backscatter data and recorded for the purposes of understanding patterns in the distribution of fluid seepage along the margin. Supplemental_Information: Additional information about the field activity from which these data were derived is available online at: https://cmgds.marine.usgs.gov/fan_info.php?fan=2018-642-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2019-636-FA https://cmgds.marine.usgs.gov/fan_info.php?fan=2021-643-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: 20180731 Ending_Date: 20211109 Currentness_Reference: Ground conditions at time data were collected Status: Progress: Complete Maintenance_and_Update_Frequency: none Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -125.065269 East_Bounding_Coordinate: -124.304200 North_Bounding_Coordinate: 46.286529 South_Bounding_Coordinate: 40.579799 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:22690c33-9099-426b-ad32-3cc5b560f028 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: distributions Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: multibeam sonar Theme_Keyword: geospatial datasets Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: oil and gas seep 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 Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: Pacific Ocean Place_Keyword: State of California Place_Keyword: State of Oregon Place: Place_Keyword_Thesaurus: None Place_Keyword: Cascadia Margin 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. 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 Browse_Graphic: Browse_Graphic_File_Name: USGS_Cascadia_Seeps_2023.jpg Browse_Graphic_File_Description: A map of the Cascadia Margin showing the point locations of the seep flares contained in this dataset. Browse_Graphic_File_Type: JPEG Native_Data_Set_Environment: This dataset was produced using QPS FMMidwater v 7.7.9 on an Apple Macbook Pro (2019) with MacOS X Monterey operating system, Microsoft Excel Workbook, and using Esri ArcGIS Pro version 3.0.3 on a Windows 10 computer. Cross_Reference: Citation_Information: Originator: Jane A. Rudebusch Originator: Nancy G. Prouty Originator: James E. Conrad Originator: Janet T. Watt Originator: Jared W. Kluesner Originator: Jenna C. Hill Originator: Nathaniel C. Miller Originator: Sally J. Watson Originator: Jess I.T. Hillman Publication_Date: 2023 Title: Diving Deeper Into Seep Distribution Along the Cascadia Convergent Margin, USA Other_Citation_Details: Rudebusch, J.A., Prouty, N.G., Conrad, J.E., Watt, J.T., Kluesner, J.W., Hill, J.C., Miller, N.C., Watson, S.J., Hillman, J.I.T. 2023. Diving Deeper into Methane Seep Distributions Along the Cascadia Convergent Margin, USA. Frontiers in Earth Science. Online_Linkage: http://XXXXXX Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The location and depth values recorded in this dataset were derived directly from the dataset’s co-located multibeam bathymetry, and therefore values are considered to have the level of accuracy to that of the multibeam data itself. Accuracy estimates of multibeam positional (x,y,z) coordinates is explained further in this metadata document. Logical_Consistency_Report: No formal logical consistency tests were conducted. Completeness_Report: Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Ship position data were provided by a Differential Global Positioning System navigation receiver with +/- 10-centimeter accuracy. The acquired water column acoustic data used for seep detection, however, are not corrected for water column diffraction. Positional error in seep locations resulting from this is negligible at nadir (directly below the ship) and increases outward in the acoustic beams perpendicular to the ship track. Although no formal accuracy assessment of the horizontal positional information in the data set has been conducted, comparison of locations of seeps detected in multiple survey tracklines indicates that horizontal positional errors are less than about 10 meters in the outer survey beams. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The acquired water-column acoustic data used for seep detection are not corrected for water-column diffraction, and no formal accuracy assessment of the horizontal positional information in the data set has been conducted. Comparison of depth values from gridded NOAA bathymetric data to those determined from water column data at seep sites indicate that the vertical positional accuracy varies from about +/- 3 meters on smooth sea floors to about +/- 10 meters in areas of steep slopes, rough seafloor, and in the outer beams of the water-column data. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: NOAA Publication_Date: 20220128 Title: Bathymetry data for H13117, H13118, H13206, H13119, H13137, H13549, W00474, and W00475 Geospatial_Data_Presentation_Form: Raster Digital Dataset Publication_Information: Publication_Place: online Publisher: NOAA Online_Linkage: https://www.ncei.noaa.gov/maps/bathymetry/ Type_of_Source_Media: Digital Resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20180731 Ending_Date: 20180731 Source_Currentness_Reference: ground condition at time data were collected Source_Citation_Abbreviation: NOAA Source_Contribution: Bathymetry data consisting of the .all and .wcd (water column data) files from surveys H13117, H13118, H13119, H13206, H13137, H13549, W00474, and W00475 were obtained from the NOAA National Centers for Environmental Information (NOAA NCEI). Process_Step: Process_Description: Bathymetry data from surveys H13117, H13118, H13119, H13206, H13137, H13549, W00474, and W00475 consisting of the .all and .wcd (water column data) files were loaded into QPS FMMidwater v 7.7.9 software running under the MacOS X Monterey operating system on an Apple MacBook Pro (2019) and converted into an internal .gwc format for water column inspection. These bathymetry data files, which typically consist of 30-minute segments of survey trackline, were then individually viewed simultaneously in an along-track view showing stacked acoustic pings and an across-track fan view usually configured to show 11 stacked acoustic pings. After adjusting acoustic backscatter gain levels to best show water column acoustic anomalies, the stacked water column data views are inspected using a survey data playback mode set to 15x or 30x normal speed. Upon recognition of seep plumes, playback mode is paused, the along-track view is switched to display a single-ping fan view of the data, and the data is manually stepped through ping-by-ping to best identify the seafloor and apparent top xyz locations of the seep plume, which are selected using a geopick tool. These locations, along with the date and time of the acoustic ping for each location, are then copied into a MS Excel spreadsheet for further analysis and import into GIS. Process_Date: 20230222 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: 902 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: D_WGS_1984 Ellipsoid_Name: WGS84 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257223563 Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: D_WGS_1984 Depth_Resolution: 1 Depth_Distance_Units: meters Depth_Encoding_Method: Attribute values Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: Point Entity_Type_Definition: A shapefile consisting of point locations indicating the geographic locations and depths of 902 fluid seeps on the seafloor of the Cascadia Margin. Entity_Type_Definition_Source: U.S. Geological Survey Attribute: Attribute_Label: FID Attribute_Definition: Internal feature number Attribute_Definition_Source: Esri Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 901 Attribute: Attribute_Label: Shape Attribute_Definition: Feature Geometry Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: The text ‘Point ZM’ indicating that objects area z-enabled features with point geometry Attribute: Attribute_Label: Seep_No Attribute_Definition: A unique identification number assigned to each seep feature. Attribute_Definition_Source: Producer defined Attribute_Domain_Values: Unrepresentable_Domain: Each seep location was assigned a unique identifier consisting of an arbitrary two-letter prefix assigned according to the NOAA survey identifier of the location, followed by a sequential whole number. Note that the numbers are not all inclusive within the range - although they were assigned sequentially during seep detection, some were eliminated from the database because they were duplicates (located on adjacent or crossing survey lines) or later determined to not represent seep plumes. Attribute: Attribute_Label: Line Attribute_Definition: The file name of the water-column data and specified line identifier from which the seep was detected. Attribute_Definition_Source: Producer defined Attribute_Domain_Values: Unrepresentable_Domain: The file name of the water-column data and specified line from which the seep was detected is assigned by NOAA during data acquisition and consists of a series of numbers and letters corresponding to the date, ship’s name, survey line, and sound receiver channel generally in the format ####_YYYYMMDD_#####_ShipName_LINE_RECCHAN#. Attribute: Attribute_Label: Date Attribute_Definition: Date of water-column data collection Attribute_Definition_Source: Producer defined Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 08/01/2018 Range_Domain_Maximum: 11/14/2021 Attribute_Units_of_Measure: month/day/year Attribute: Attribute_Label: Time Attribute_Definition: The timestamp of the acoustic ping where the seep registered in the water-column data. Attribute_Definition_Source: Producer defined Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 00:16:07 Range_Domain_Maximum: 23:37:08 Attribute_Units_of_Measure: UTC Attribute: Attribute_Label: Longitude Attribute_Definition: Geographic position of the seep in decimal degrees longitude. Attribute_Definition_Source: Ship GPS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -124.304200 Range_Domain_Maximum: -125.065269 Attribute_Units_of_Measure: decimal degrees Attribute_Measurement_Resolution: 0.000001 Attribute: Attribute_Label: Latitude Attribute_Definition: Geographic position of the seep in decimal degrees latitude. Attribute_Definition_Source: Ship GPS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 40.579799 Range_Domain_Maximum: 46.286529 Attribute_Units_of_Measure: decimal degrees Attribute_Measurement_Resolution: 0.000001 Attribute: Attribute_Label: Depth Attribute_Definition: The recorded depth measurement of the seep. Attribute_Definition_Source: Producer defined Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 92 Range_Domain_Maximum: 1372 Attribute_Units_of_Measure: meters Attribute_Measurement_Resolution: 1 Attribute: Attribute_Label: Rise Attribute_Definition: The maximum estimated height of the bubble plume observed in the water column. Attribute_Definition_Source: Producer defined Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 4 Range_Domain_Maximum: 1032 Attribute_Units_of_Measure: meters Attribute_Measurement_Resolution: 1 Attribute: Attribute_Label: Comments Attribute_Definition: Qualitative observations about the appearance, size, and/or quantity of the seep flares. Attribute_Definition_Source: Producer defined Attribute_Domain_Values: Unrepresentable_Domain: Comments were made by J.E. Conrad to qualitatively describe the seep flares in terms of their size or quantity as they appeared in the water-column processing environment. Some fields are blank, meaning no notable observations were made about those seeps. Attribute: Attribute_Label: SurveyID Attribute_Definition: The identifier of the multibeam survey corresponding with the water column data and the associated seeps from that survey data. Attribute_Definition_Source: NOAA Attribute_Domain_Values: Unrepresentable_Domain: The name of the multibeam survey from which the water-column data and seep location were derived. Survey IDs are assigned by NOAA and consist of a letter (H or W in this dataset) and a five-digit number. This ID can be used to search for the multibeam and water-column data used to create this dataset at NCEI. Overview_Description: Entity_and_Attribute_Overview: Zip file of seep flare locations in shapefile format. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey 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: 1-831-427-4747 Contact_Electronic_Mail_Address: pcmsc_data@usgs.gov Resource_Description: These data are available in shapefile format (USGS_Cascadia_Seeps_2023.shp and associated files) contained in a single zip file (USGS_Cascadia_Seeps_2023.zip) 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: shapefile Format_Version_Number: ArcGIS Pro (version 3.0.1) Format_Information_Content: Zip file contains point shapefile of seep locations. File_Decompression_Technique: The downloadable data file has been compressed with the "zip" command and can be unzipped with Winzip (or other tool) on Windows systems. To utilize these data, the user must have software capable of uncompressing the WinZip file. The shapefile can be and imported and viewed using a geographic information system (GIS). Transfer_Size: 0.0662 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P9TW2X7Y Access_Instructions: Data can be downloaded using the Network_Resource_Name link and scrolling to the Environmental Data section. Fees: None. Technical_Prerequisites: Shapefile navigation data can be viewed using any Geographic Information System (GIS) software (for example, ArcGIS, QGIS). Metadata_Reference_Information: Metadata_Date: 20230808 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