3dc88bc6166972a044f3d1fdb57b6fb5 English dataset David Gordon Gardline Limited Principle Client Reporting Manager dassh.enquiries@mba.ac.uk pointOfContact 2018-10-10 MEDIN Discovery metadata standard 2.3.8 urn:ogc:def:crs:EPSG::4258 11209 HOW03 GP1B Lot 4 Geophysical UHR Survey 2018 - Magnetometer 2018-09-19 publication 11209 Wind Farm Identifier: HOW03 LOT4; Survey Details: Geophysical 1b pre-geotechnical UXO survey acquiring magnetometer array, bathymetry, side scan sonar, sub bottom profiler, ultra-high resolution multichannel seismic and environmental grab sample data across wind farm and along export cable corridor. Acquired by Gardline Limited. Geophysical Acquisition Dates 2018-05-01 to 2018-09-07. Projection: Horizontal datum: ETRS89 (2018.0) Ellipsoid name: GRS 1980 Coordinate system: UTM 31N Vertical Datum LAT David Gordon Gardline Limited Principle Client Reporting Manager dassh.enquiries@mba.ac.uk originator David Gordon Gardline Limited Principle Client Reporting Manager dassh.enquiries@mba.ac.uk custodian continual Marine Environmental Data and Information Network Elevation Hydrography GEMET - INSPIRE themes, version 1.0 2008-01-06 revision Bathymetry and Elevation SeaDataNet P021 parameter discovery vocabulary 2009-11-16 revision Use of this data requires approval from Orsted otherRestrictions Use of this data requires approval from Orsted English elevation inlandWaters 2.2100 2.7900 53.6900 54.0000 2018-05-01 2018-09-07 26.9800 72.9100 David Gordon Gardline Limited Principle Client Reporting Manager dassh.enquiries@mba.ac.uk distributor dataset Magnetometer Raw Data, Vessel: M.V. Ocean Endeavour Equipment Type: Geometrics G882 Caesium Vapour Magnetometer. Navigation Data Processing carried out using Gardline in House Voyager5 Software. Raw USBL data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in a shapefile format. No data processing was carried out on the Magnetometer data. Total Positional Uncertainty derived from the Ranger 2 USBL System 0.4% 1DRMS. Ping Rate 10Hz. Data created using Geosoft Oasis Montaj. Processed Magnetometer Data, Vessel: M.V. Ocean Endeavour Equipment Type: Geometrics G882 Magnetometer at a ping rate of 10Hz. Navigation Supplied using Sonardyne Ranger USBL Navigation Data Processing carried out using Gardline in House Voyager5 Software. Raw data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in a shapefile format. Data Processing carried out using Geosoft Oasis Montaj Version 9.1.3. Data is despiked and data points outside of depth tolerance masked. The Clean Total Field is then filtered and smoothed before being subtracted from the result to produce the Residual Field. Total Positional Uncertainty derived from USBL - 0.4% 1DRMS. Magnetometer Residual Field Grid, Vessel: M.V. Ocean Endeavour Equipment Type: Geometrics G882 Magnetometer and Sonardyne Ranger USBL System. Navigation Data Processing carried out using Gardline in House Voyager5 Software. Raw USBL data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in our Gardline Sensor file format. Magnetometer Data processing has been carried out using Geosoft Oasis Montaj Version 9.1.3. Data were subject to despiking, a Non Linear Filter (800 samples, tolerance of 0.5) to fit a background to the dataset, then subtracted from total field to give the residual. Residual gridding with a 1m grid cell size and a 20m blanking distance. Total Positional Uncertainty derived from the USBL data - 0.4% at 1DRMS. Data Resolution - 1m x 1m. Blanking Distance - 20m. Magnetometer Total Field Grid, Vessel: M.V. Ocean Endeavour Equipment Type: Geometrics G882 Magnetometer and Sonardyne Ranger USBL System. Navigation Data Processing carried out using Gardline in House Voyager5 Software. Raw USBL data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in our Gardline Sensor file format. Magnetometer Data processing has been carried out using Geosoft Oasis Montaj Version 9.1.3. Data were subject to Despiking then Minimum Curvature gridding with a 1m grid cell size and 20m blanking distance. Navigation Data Collected. Total Positional Uncertainty derived from the USBL data - 0.4% at 1DRMS. Data Resolution - 1m x 1m. Blanking Distance - 20m. Magnetometer Signal Strength Grid, Vessel: M.V. Ocean Endeavour Equipment Type: Geometrics G882 Magnetometer and Sonardyne Ranger USBL System. Navigation Data Processing carried out using Gardline in House Voyager5 Software. Raw USBL data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in our Gardline Sensor file format. Magnetometer Data processing has been carried out using Geosoft Oasis Montaj Version 9.1.3. Data were subject to a direct gridding algorithm with a 1m grid cell size prior to export. Navigation Data Collected. Total Positional Uncertainty derived from the USBL data - 0.4% at 1DRMS. Data Resolution - 1m x 1m. Magnetometer Altitude Grid, Vessel: M.V. Ocean Endeavour Equipment Type: Geometrics G882 Magnetometer and Sonardyne Ranger USBL System. Navigation Data Processing carried out using Gardline in House Voyager5 Software. Raw USBL data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in our Gardline Sensor file format. Magnetometer Data processing has been carried out using Geosoft Oasis Montaj Version 9.1.3. Data were subject to despiking and a direct gridding algorithm with a 1m grid cell size prior to export. Navigation Data Collected. Total Positional Uncertainty derived from the USBL data - 0.4% at 1DRMS. Data Resolution - 1m x 1m Oasis Montaj Magnetometer Processing Project, Vessel: M.V. Ocean Endeavour Equipment Type: Sonardyne Ranger USBL and Geometrics G882 Magnetometer. Navigation Data Processing carried out using Gardline in House Voyager5 Software. Raw data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in a sensor format. All raw magnetometer data, all processed magnetometer data and magnetometer targets database were loaded processing carried out using Geosoft Oasis Montaj Version 9.1.1. Loaded into the project is raw magnetometer data, processed magnetometer data and targets all in individual databases. Database file type within Oasis: .gdb (compressed for size). Data line paths and magnetometer altitude, signal strength, residual, total field and analytical signal grids all loaded on to the Map. Map Scale: 120,000. Grid file type within Oasis: .grd (32-bit float). Total Positional Uncertainty derived from the USBL System - 0.4% 1DRMS. No decimation is applied. Magnetic anomalies SHP and CSV. Vessel: M.V. Ocean Endeavour. Equipment Type: Fugro Starpack Navigation Package, Geometrics G882 Magnetometer and Sonardyne Ranger USBL System. Navigation Data Processing Carried out using Gardline in House Voyager5 Software. Raw USBL data were opened in Voyager5 and manually checked and corrected for any spikes or erroneous points. Once data cleaning has been carried out a light smooth filter of 11 points was added to the data which was then exported in our Gardline Sensor file format. Magnetometer Data processing has been carried out using Geosoft Oasis Montaj Version 9.1.1. Data were subject to despiking, a Non Linear Filter (800 samples, tolerance of 0.5) to fit a background to the dataset, then subtracted from total field to give the residual. This residual will then be gridded at an appropriate grid cell size and blanking distance using the minimum curvature gridding method, and derivative grids calculated, along with a final Analytical Signal (AS) grid, which represents the gradient of an anomaly in nT/m. This AS grid will be used for target picking utilizing the Blakely Test in Oasis Montaj. The targets will then be reviewed, and duplicate targets on the same anomaly removed, this will leave a single target for each anomaly. Magnetometer targets are classified as anomalies unless there is a an associated seafloor contact, in which case the target will be classified as debris unless it is known infrastructure, a wreck or fishing equipment/pots. Total Positional Uncertainty derived from the Ranger 2 USBL System 0.4% 1DRMS. The minimum threshold for target analysis was 2nT.