Metadata: Identification_Information: Citation: Citation_Information: Originator: Janet T. Watt Originator: Ray W. Sliter Originator: James E. Conrad Originator: Thomas D. Lorenson Originator: Antoinette G. Papesh Originator: Jonathan A. Warrick Publication_Date: 2021 Title: Marine magnetic data collected offshore San Francisco, California, during field activity 2019-649-FA from 2019-10-11 to 2019-10-18 Geospatial_Data_Presentation_Form: comma-delimited text Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9LBG9H5 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/P9LBG9H5 Larger_Work_Citation: Citation_Information: Originator: Ray W. Sliter Originator: James E. Conrad Originator: Thomas D. Lorenson Originator: Antoinette G. Papesh Originator: Alicia F. Balster-Gee Originator: Janet T. Watt Originator: Jonathan A. Warrick Publication_Date: 2021 Title: Geophysical and core sample data collected offshore San Francisco, California, during field activity 2019-649-FA from 2019-10-11 to 2019-10-18 Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P9LBG9H5 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/P9LBG9H5 Description: Abstract: This part of the data release contains marine magnetic data that were collected aboard the R/V Bold Horizon in 2019 on U.S. Geological Survey Field Activity 2019-649-FA offshore San Francisco, California. Purpose: The U.S. Geological Survey (USGS) collected marine magnetic in 2019 offshore San Francisco, California. The goal of the magnetic survey was to provide magnetic field data to characterize the surface and subsurface properties of the study area, including unconsolidated sediment thickness and subsurface sediment horizons. This cruise was funded through partnerships with the Bureau of Ocean Energy Management (BOEM) and the State of California Ocean Protection Council (OPC). 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=2019-649-FA Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20191011 Ending_Date: 20191018 Currentness_Reference: ground condition at time data were collected Status: Progress: Planned Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -122.87083 East_Bounding_Coordinate: -122.39324 North_Bounding_Coordinate: 38.01347 South_Bounding_Coordinate: 37.49665 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:ddb08b78-74bf-48c2-9328-b6412031aa88 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: substrate Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: sea-floor characteristics Theme_Keyword: magnetic field (earth) Theme_Keyword: geophysics Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: continental margin Theme_Keyword: magnetic field observations Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: 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: San Francisco Place_Keyword: Bolinas Place_Keyword: Ocean Beach Place: Place_Keyword_Thesaurus: NGA GEOnet Names Server (GNS) Place_Keyword: North 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 (USGS, the Bureau of Ocean Energy Management (BOEM), and the California Geological Survey (CGS) 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: 2019-649-FA_magnetics_map.png Browse_Graphic_File_Description: Map showing magnetic anomaly data. Browse_Graphic_File_Type: PNG Native_Data_Set_Environment: comma separated file Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: Identified as best available version 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. Users are advised to read the rest of the metadata record carefully for additional details. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Position data were provided by a Hemisphere V100 Global Positioning System using L1, C/A code and carrier phase smoothing with a stated accuracy of 60 centimeters. Lineage: Process_Step: Process_Description: Magnetic field data were collected using a Geometrics G882 cesium-vapor marine magnetometer. Survey speeds were approximately 4.5 knots. Process_Date: 20191018 Process_Step: Process_Description: Magnetic data were postprocessed following the methodology: 1)Initial Processing in MagMap2000 -Download base files from INTERMAGNET observatory (http://www.intermagnet.org/apps/dl_data_prel_e.php) -Despike base files and visually inspect for dropouts. Data were only lightly edited and may require additional noise-editing and/or heading corrections to make fully interpretable. -Apply time-offset to DIURNAL (base) readings for GMT to local PDT + longitude difference from base to survey = -7hrs + 0.15hrs =-24,660sec **NOTE: 0.0666667hr/deg longitude correction -Import .survey files, despike -Export files as Geosoft .xyz 2)Import to Oasis-Montaj 3)Calculated DGRF for G882 data and FRN base station = DGRF_G882 and DGRF_FRN. IGRF 13 Generation model was calculated per Alken and others (2021), https://doi.org/10.1186/s40623-020-01288-x. *NOTE: for survey dates 10/11/19 and 10/12/19, DGRF calculated in Oasis montaj (OM) was incorrect. DGRF values for these two days were corrected by applying a DC shift to the OM values based on DGRF value calculated using the following online calculator (http://geomag.bgs.ac.uk/data_service/models_compass/igrf_calc.html). 4)Back calculated FRN Base Magnetometer measurements because they are NOT exported from MagMap2000 G882-DIURNAL_1 = FRN_base 5)Calculated DGRF value at base station FRN = 48138nT 6)Calculated Total Field (Residual) Anomaly (Resid_anom) using the following equation: A(x) = [F(x,t) - I(x)] - [FB(t) - IB] where: A(x)is total field anomaly at position x F(x,t) is the G882 reading at time t and position x I(x) is IGRF/DGRF at the G882 FB(t) is the base station reading at time t IB is the IGRF/DGRF at the base station Projection is UTM z10N, wgs84. Process_Date: 20210601 Process_Step: Process_Description: Performed minor edits to the metadata to correct typos. No data were changed Process_Date: 20211013 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Susan A. Cochran Contact_Position: Geologist Contact_Address: Address_Type: Mailing and Physical Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-460-7545 Contact_Electronic_Mail_Address: scochran@usgs.gov 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: 366908 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Map_Projection: Map_Projection_Name: WGS 1984 UTM Zone 11N Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.9996 Longitude_of_Central_Meridian: -117.0 Latitude_of_Projection_Origin: 0.0 False_Easting: 500000.0 False_Northing: 0.0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: coordinate pair Coordinate_Representation: Abscissa_Resolution: 0.0001 Ordinate_Resolution: 0.0001 Planar_Distance_Units: Meter 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: 2019-649-FA_magnetics Entity_Type_Definition: Points representing magnetic field anomaly value in nanoteslas (nT) Entity_Type_Definition_Source: USGS Attribute: Attribute_Label: lon_dec_deg Attribute_Definition: Longitude of data point in decimal degrees Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -122.709864 Range_Domain_Maximum: -122.517473 Attribute: Attribute_Label: lat_dec_deg Attribute_Definition: Latitude of data point in decimal degrees Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 37.566820 Range_Domain_Maximum: 37.893757 Attribute: Attribute_Label: G882_raw Attribute_Definition: Raw, unprocessed, total magnetic field value at G882 in nanoteslas (nT) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 47411.66 Range_Domain_Maximum: 48291.94 Attribute: Attribute_Label: DIURNAL Attribute_Definition: Diurnal field correction at each G882 measurement in nanoteslas (nT) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -512.35 Range_Domain_Maximum: 369.45 Attribute: Attribute_Label: LINE Attribute_Definition: Survey line identifier Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Each line contained in the survey has a unique identifier Attribute: Attribute_Label: TIME Attribute_Definition: Time of data point collection in HH:MM:SS format Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 00:00:00 Range_Domain_Maximum: 24:00:00 Attribute: Attribute_Label: DATE Attribute_Definition: Date of data point collection in M/DD/YY format Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 10/11/19 Range_Domain_Maximum: 10/18/19 Attribute: Attribute_Label: utm_x Attribute_Definition: X coordinate of data point in meters Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 525548.83 Range_Domain_Maximum: 542581.75 Attribute: Attribute_Label: utm_y Attribute_Definition: Y coordinate of data point in meters Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 4157812.93 Range_Domain_Maximum: 4194084.46 Attribute: Attribute_Label: DGRF_G882 Attribute_Definition: Definitive Geomagnetic Reference Field (DGRF) value at each G882 measurement in nanoteslas (nT) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 47798.58 Range_Domain_Maximum: 48075.47 Attribute: Attribute_Label: FRN_base Attribute_Definition: back-calculated total magnetic field value at base station in nanoteslas (nT) because they are NOT exported from MagMap2000 Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 47908.55 Range_Domain_Maximum: 47937.75 Attribute: Attribute_Label: DGRF_FRN Attribute_Definition: Definitive Geomagnetic Reference Field (DGRF) value at the base station in nanoteslas (nT) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 48138 Range_Domain_Maximum: 48138 Attribute: Attribute_Label: Resid_anom Attribute_Definition: Calculated Total Field (Residual) Anomaly (see Process Step 6) in nanoteslas (nT) Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -282.14 Range_Domain_Maximum: 597.78 Overview_Description: Entity_and_Attribute_Overview: The first line of the csv file is a header line. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Pacific Coastal and Marine Science Center 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: Downloadable magnetic field data. These data are available in comma separated format (2019-649-FA_magnetics.csv) and shapefile format (2019-649-FA_magnetics_shape.zip) 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: comma-delimited text Format_Version_Date: 20210609 Format_Information_Content: 2019-649-FA_magnetics.csv is tabular magnetics data Transfer_Size: 39.2 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P9LBG9H5 Access_Instructions: Data can be downloaded using the Network_Resource_Name link, then scroll down to the Magnetic Data section. Digital_Form: Digital_Transfer_Information: Format_Name: shapefile Format_Version_Date: 20210607 Format_Information_Content: 2019-649-FA_magnetics_shape.zip is a shapefile of magnetic residual anomalies File_Decompression_Technique: Winzip, 7-zip, or Winrar are free software that will open .zip files Transfer_Size: 14.1 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://doi.org/10.5066/P9LBG9H5 Access_Instructions: Data can be downloaded using the Network_Resource_Name link, then scroll down to the Magnetic Data section. Fees: None. Technical_Prerequisites: These data can be viewed with Microsoft Excel software. Metadata_Reference_Information: Metadata_Date: 20211013 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