Metadata: Identification_Information: Citation: Citation_Information: Originator: Antoinette G. Papesh Originator: Maureen L. Walton Originator: James E. Conrad Originator: Daniel S. Brothers Originator: Jared W. Kluesner Originator: Mary L. McGann Publication_Date: 20230821 Title: Landslide debris aprons offshore of southern California, 2023 Geospatial_Data_Presentation_Form: polygon shapefile Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9IIWTYL Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9IIWTYL Online_Linkage: https://www.sciencebase.gov/catalog/item/5ef12a2682ced62aaae18f67 Larger_Work_Citation: Citation_Information: Originator: Antoinette G. Papesh Originator: Maureen L. Walton Originator: James E. Conrad Originator: Daniel S. Brothers Originator: Jared W. Kluesner Originator: Mary L. McGann Publication_Date: 2023 Title: Digital maps of submarine landslides and mass wasting features offshore of southern California, 2023 Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9IIWTYL Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/P9IIWTYL Description: Abstract: Landslide debris aprons have been mapped offshore of Southern California. Polygons were mapped from visual interpretation of high-resolution multibeam echosounder data (MBES), single-beam echosounder data, and seismic reflection data. Purpose: These data were compiled as a part of a USGS effort to understand the geologic processes of mass wasting offshore of Southern California. They are intended to provide baseline knowledge of the geology, geomorphology, and distribution of landslides debris aprons offshore of Southern California, for use by scientists, managers, and the general public. These data can be used with geographic information systems (GIS) software for research purposes. Supplemental_Information: 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: 1998 Ending_Date: 20210730 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -120.913005 East_Bounding_Coordinate: -117.313146 North_Bounding_Coordinate: 34.517488 South_Bounding_Coordinate: 32.465078 Keywords: Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: oceans Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: Distributions Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: scientific interpretation Theme_Keyword: geospatial datasets Theme_Keyword: earth characteristics Theme_Keyword: sea-floor characteristics Theme_Keyword: marine geophysics Theme_Keyword: marine geology Theme_Keyword: landslides Theme_Keyword: hazards Theme_Keyword: geologic processes Theme_Keyword: oceanic lithosphere Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: natural agents of coastal change Theme_Keyword: geology Theme_Keyword: geophysics Theme_Keyword: geological features Theme_Keyword: hazards and disasters Theme_Keyword: earthquake effects Theme_Keyword: geologic mapping Theme_Keyword: oceanographic 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: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:5ef12a2682ced62aaae18f67 Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: United States of America Place_Keyword: State of California Place_Keyword: Pacific Ocean 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: debrisaprons_offshore_socal_2023_thumb.png Browse_Graphic_File_Description: Southern California location map with bathymetry and mapped debris aprons Browse_Graphic_File_Type: PNG Native_Data_Set_Environment: Mac Pro, Late 2013, with macOS High Sierra, version 10.13.6 running Parallels Virtual Machine; ESRI ArcGIS 10.7. Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: No formal attribute accuracy tests were conducted. Logical_Consistency_Report: No formal logical accuracy tests were conducted. Completeness_Report: Dataset is considered complete for the information presented, as described in the abstract. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: These data and associated attributes have been created from several bathymetric datasets. Landslide debris apron mapping was cross-checked where more than one bathymetric dataset spanned a suspected landslide debris apron. The accuracy of debris apron mapping correlates to the highest resolution dataset that spans a particular debris apron. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: Peter Dartnell Originator: Neal W. Driscoll Originator: Daniel S. Brothers Originator: James E. Conrad Originator: Jared Kluesner Originator: Graham Kent Originator: Brian D. Andrews Publication_Date: 2015 Title: Colored shaded-relief bathymetry, acoustic backscatter, and selected perspective views of the inner continental borderland, southern California Geospatial_Data_Presentation_Form: Raster Digital Data Set Series_Information: Series_Name: Scientific Investigations Map Issue_Identification: DOI:10.3133/sim3324 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.3133/sim3324 Type_of_Source_Media: Digital Resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1998 Ending_Date: 2014 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Dartnell and others, 2015 Source_Contribution: High resolution multibeam bathymetry was used as a base layer to begin drawing polygons for landslide interpretation. Source_Information: Source_Citation: Citation_Information: Originator: Peter Dartnell Originator: Emily C. Roland Originator: Nicole A. Raineault Originator: Christopher M. Castillo Originator: James E. Conrad Originator: Renato Kane Originator: Daniel S. Brothers Originator: Jared W. Kluesner Originator: Maureen A. L. Walton Publication_Date: 2021 Title: Colored shaded-relief bathymetry, acoustic backscatter, and selected perspective views of the northern part of the California Continental Borderland, southern California Geospatial_Data_Presentation_Form: Raster Digital Data Set Series_Information: Series_Name: Scientific Investigations Map Issue_Identification: DOI:10.3133/sim3473 Publication_Information: Publication_Place: Reston, VA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.3133/sim3473 Type_of_Source_Media: Digital resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1998 Ending_Date: 2018 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Dartnell and others, 2021 Source_Contribution: High resolution multibeam bathymetry was used as a base layer to begin drawing polygons for landslide interpretation. This is a compilation of publicly available multibeam bathymetry data published at various resolutions ranging from 2-30 meters. Data sources used are shown on Figure 1 of the report and links to the data are provided therein. Source_Information: Source_Citation: Citation_Information: Originator: Seafloor Mapping Lab of California State University Monterey Bay Publication_Date: 2018 Title: California Margin Geology Series Geospatial_Data_Presentation_Form: Raster Digital Data Sets Publication_Information: Publication_Place: Seaside, CA Publisher: California State University, Monterey Bay Online_Linkage: http://seafloor.otterlabs.org/SFMLwebDATA.htm Type_of_Source_Media: Digital resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 2000 Ending_Date: 2018 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Seafloor Mapping Lab, 2018 Source_Contribution: High resolution multibeam bathymetry was used as a base layer to begin drawing polygons for landslide interpretation. High resolution multibeam bathymetry data at resolutions ranging from 2 – 10 meters from survey datasets H11875, H11876, H11877, H11878, H11879, H11880, H11881, H11882, H11883, H11891, H11950, H11951, H11952, H11953, and the 2014 Southern California Data Gap Project (Dana Point, San Onofre Blocks 01-03, La Jolla, Mission Beach, Point Loma North, Point Loma South, and Imperial Beach) were used. Source_Information: Source_Citation: Citation_Information: Originator: MBARI Seafloor Mapping Team Publication_Date: 2001 Title: Santa Barbara multibeam survey Geospatial_Data_Presentation_Form: Raster Digital Data Set Publication_Information: Publication_Place: online Publisher: MBARI Online_Linkage: https://www3.mbari.org/data/mapping/Santa_Barbara_Basin/ Type_of_Source_Media: Digital resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1998 Ending_Date: 2001 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: MBARI Seafloor Mapping Team, 2001 Source_Contribution: High resolution multibeam bathymetry was used as a base layer to begin drawing polygons for landslide interpretation. This is 20-meter resolution bathymetry data. Source_Information: Source_Citation: Citation_Information: Originator: NOAA Publication_Date: 2012 Title: U.S. Coastal Relief Model - Southern California vers. 2 Geospatial_Data_Presentation_Form: Raster Digital Data Sets Publication_Information: Publication_Place: online Publisher: NOAA Online_Linkage: https://doi.org/10.7289/V5V985ZM Type_of_Source_Media: Digital resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19990101 Ending_Date: Present Source_Currentness_Reference: published 2013-07-08 Source_Citation_Abbreviation: National Geophysical Data Center, 2012 Source_Contribution: The NCEI 3-arc-second elevation grid (approximately 90-meter resolution) was used as a base layer to begin drawing polygons for landslide interpretation where no high resolution multibeam bathymetry data (listed above) were available. Source_Information: Source_Citation: Citation_Information: Originator: Ray W. Sliter Originator: James E. Conrad Originator: Holly F. Ryan Originator: Peter J. Triezenberg Publication_Date: 2017 Title: Minisparker seismic-reflection data of field activity S-12-10-SC: Oceanside to La Jolla, offshore southern California from 2010-06-01 to 2010-06-12 Geospatial_Data_Presentation_Form: seismic-reflection data in SEG-Y format Series_Information: Series_Name: Data Release Issue_Identification: DOI:10.5066/F7QN64W8 Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/F7QN64W8 Online_Linkage: https://cmgds.marine.usgs.gov/data-releases/datarelease/10.5066-F7QN64W8/ Type_of_Source_Media: Digital resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20100601 Ending_Date: 20100612 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Sliter and others, 2017a Source_Contribution: Seismic reflection profiles were used to map extent of debris apron for the Del Mar slide. Source_Information: Source_Citation: Citation_Information: Originator: Ray W. Sliter Originator: James E. Conrad Originator: Holly F. Ryan Originator: Peter J. Triezenberg Publication_Date: 2017 Title: Minisparker seismic-reflection data of field activity S-07-11-SC: offshore San Diego, and Los Angeles Counties, southern California from 2011-06-08 to 2011-06-22 Geospatial_Data_Presentation_Form: seismic-reflection data in SEG-Y format Series_Information: Series_Name: Data Release Issue_Identification: DOI:10.5066/F7SF2TCV Publication_Information: Publication_Place: Pacific Coastal and Marine Science Center, Santa Cruz, CA Publisher: U.S. Geological Survey Online_Linkage: https://doi.org/10.5066/F7SF2TCV Online_Linkage: https://cmgds.marine.usgs.gov/data-releases/datarelease/10.5066-F7SF2TCV/ Type_of_Source_Media: Digital resource Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20110608 Ending_Date: 20110622 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: Sliter and others, 2017b Source_Contribution: Seismic reflection profiles were used to map extent of debris apron for the San Gabriel Slide Complex. Process_Step: Process_Description: A compilation of existing bathymetry data was used as a base layer to map landslide features. Data from listed sources was downsampled in ESRI ArcMap and merged into a single 30-m grid to create the base layer. In some cases, the source swath data was higher resolution than the 30-m compilation and was used to map landslide features. A list of source swath data is detailed in the Source Used Citations. Where high (<30 m) resolution data was unavailable, the 90-m resolution NOAA Coastal Relief Model was used as the base layer. Using this base layer, landslides, headwall scarps, and areas of mass-wasting were mapped. Mapped landslide bodies were divided into evacuation zones and debris aprons based on negative (i.e., evacuation zones) or positive (i.e., debris aprons) seafloor relief associated with the landslide masses. Source_Used_Citation_Abbreviation: Dartnell and others, 2015 Source_Used_Citation_Abbreviation: Dartnell and others, 2021 Source_Used_Citation_Abbreviation: Seafloor Mapping lab, 2018 Source_Used_Citation_Abbreviation: MBARI Seafloor Mapping Team, 2001 Source_Used_Citation_Abbreviation: NOAA National Geophysical Data Center, 2012 Source_Used_Citation_Abbreviation: Sliter and others, 2017a Source_Used_Citation_Abbreviation: Sliter and others, 2017b Process_Date: 20230202 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Vector Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: GT-polygon composed of chains Point_and_Vector_Object_Count: 63 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.0001 Longitude_Resolution: 0.0001 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: D_WGS_1984 Ellipsoid_Name: WGS_1984 Semi-major_Axis: 6378137.0 Denominator_of_Flattening_Ratio: 298.257223563 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: debrisaprons_offshore_socal_2023 Entity_Type_Definition: polygons representing mapped landslide debris aprons 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: automatically generated sequential unique whole number identifier Attribute: Attribute_Label: Shape Attribute_Definition: feature geometry Attribute_Definition_Source: Esri Attribute_Domain_Values: Unrepresentable_Domain: feature type Attribute: Attribute_Label: name_id Attribute_Definition: the name of the debris apron Attribute_Definition_Source: U.S. Geological Survey and California Geological Survey Attribute_Domain_Values: Unrepresentable_Domain: The names of the landslide debris aprons are identical to the names of the landslide feature in which the debris apron belongs (see landslides_offshore_socal_2023.shp, available elsewhere in this data release). We define prefixes as follows: CB is Catalina Basin; CI is Catalina Island; GSC is Gulf of Santa Catalina; PA is Point Arguello; SBB is Santa Barbara Basin; SClB is San Clemente Basin; SCB is Santa Cruz Basin; SDT is San Diego Trough; SG is San Gabriel; SNB is San Nicolas Basin; SPB is San Pedro Basin. Attribute: Attribute_Label: area_m2 Attribute_Definition: Area of debris apron in square meters Attribute_Definition_Source: Esri Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 19963 Range_Domain_Maximum: 196388611 Attribute_Units_of_Measure: square meters Attribute_Measurement_Resolution: 1 Attribute: Attribute_Label: area_err Attribute_Definition: Estimated uncertainty of debris apron area from data resolution and user interpretation, values in square meters. GIS-calculated area was approximated as a circle geometry with radius uncertainty of plus or minus 50 meters and plus or minus 20 meters for areas greater and less than 100,000 square meters, respectively. These values are based on 2 pixels of the likely resolution of bathymetric data used for mapping (25-meter and 10-meter resolutions). The calculated error is the standard deviation of the maximum, minimum, and picked geometries. Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 10043 Range_Domain_Maximum: 2481440 Attribute_Units_of_Measure: square meters Attribute_Measurement_Resolution: 1 Overview_Description: Entity_and_Attribute_Overview: Polygon shapefile containing outlines and attributes of landslide debris aprons offshore of Southern California Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey - ScienceBase Contact_Address: Address_Type: Mailing and Physical Address: Denver Federal Center, Building 810, Mail Stop 302 City: Denver State_or_Province: CO Postal_Code: 80225 Contact_Voice_Telephone: 1-888-275-8747 Contact_Electronic_Mail_Address: sciencebase@usgs.gov Resource_Description: debrisaprons_offshore_socal_2023.zip contains the shapefile and associated files, and is accompanied by a browse image and 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 10.7 Format_Specification: polygon shapefile Format_Information_Content: Zip file contains the interpreted polygons shapefiles and the associated metadata File_Decompression_Technique: Winzip, 7-zip, or Winrar are free software that will open .zip files. Transfer_Size: 0.04 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://www.sciencebase.gov/catalog/file/get/5ef129c982ced62aaae18f67 Network_Resource_Name: https://www.sciencebase.gov/catalog/item/5ef129c982ced62aaae18f67 Network_Resource_Name: https://doi.org/10.5066/P9IIWTYL Access_Instructions: Data can be downloaded using the Network_Resource_Name links. The first link is a direct link to download the zipped file of data and metadata. The second link points to a landing page with metadata and data. The third link points to the landing page for the entire data release. Fees: None. Technical_Prerequisites: These data can be viewed with GIS software. Metadata_Reference_Information: Metadata_Date: 20230821 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