776612d1-573c-49c4-aff5-23b0fba48271 eng utf8 dataset dataset NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom polardatacentre@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact 2019-09-24 ISO 19115 Geographic Information - Metadata ISO 19115:2003(E) European Petroleum Survey Group (EPSG) Geodetic Parameter Registry 2008-11-12 publication European Petroleum Survey Group EPSGadministrator@iogp.org https://www.epsg-registry.org/ EPSG Geodetic Parameter Dataset The EPSG Geodetic Parameter Dataset is a structured dataset of Coordinate Reference Systems and Coordinate Transformations, accessible through this online registry. information publisher urn:ogc:def:crs:EPSG::3031 6.18.3 Processed line aeromagnetic data over the Thwaites glacier region (2018/19 season) 2019-09-24 creation 2019-09-24 revision 2019-09-24 publication 2019-09-24 released 1.0 https://doi.org/10.5285/776612d1-573c-49c4-aff5-23b0fba48271 doi GB/NERC/BAS/PDC/01240 https://data.bas.ac.uk/ Please cite this item as: Jordan, T., Robinson, C., & Porter, D. (2020). Processed line aeromagnetic data over the Thwaites glacier region (2018/19 season) (Version 1.0) [Data set]. UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation. https://doi.org/10.5285/776612d1-573c-49c4-aff5-23b0fba48271 Aeromagnetic data provides important constraints on the sub-surface geology of a region. This dataset contains aeromagnetic line data collected by the British Antarctic Survey as part of the International Thwaites Glacier Collaboration (ITGC). Data were collected using a caesium magnetometer system, and have been corrected to total field values following the approach laid out by the SCAR ADMAP working group https://www.scar.org/science/admap/about/. Across flow flights were generally flown at a constant altitude ~450 m above the ice surface, but data was also collected along draped sections flown along the ice flow direction. In total 9872 km of data is presented, of this 6033 km was collected in the main survey area, while other data was collected on input transit flights. The aircraft used was the BAS aerogeophysicaly equipped twin otter VP-FBL. Data are available in ASCII file format (.xyz). No credit. completed Jordan, Tom British Antarctic Survey Researcher author Robinson, Carl British Antarctic Survey Researcher author Porter, David Lamont Doherty Earth Observatory Researcher author NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information pointOfContact asNeeded completed EARTH SCIENCE > Oceans > Marine Geophysics > Magnetic Anomalies EARTH SCIENCE > Cryosphere > Glaciers/Ice Sheets theme Global Change Master Directory (GCMD) Science Keywords 2026-01-27 publication 23 Global Change Data Center, Science and Exploration Directorate, Goddard Space Flight Center (GSFC) National Aeronautics and Space Administration (NASA) Greenbelt MD United States of America https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords Global Change Master Directory (GCMD) Keywords The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. information publisher Antarctica Crosson Ice Shelf Dotson Ice Shelf Geophysics ITGC Magnetic Thwaites Glacier theme Thwaites Glacier Antarctica Dotson Ice Shelf Antarctica Crosson Ice Shelf Antarctica place Oceanographic geographical features Elevation theme GEMET - INSPIRE themes, version 1.0 2021-01-06 revision otherRestrictions no limitations to public access otherRestrictions no limitations license Open Government Licence v3.0 otherRestrictions This data is governed by the NERC Data Policy: https://www.ukri.org/who-we-are/nerc/our-policies-and-standards/nerc-data-policy/ otherRestrictions Further by downloading this data the user acknowledges that they agree with the NERC data policy (), and the following conditions: 1. To cite the data in any publication as follows: Jordan, T., Robinson, C., & Porter, D. (2020). Processed line aeromagnetic data over the Thwaites glacier region (2018/19 season) [Data set]. UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation. https://doi.org/10.5285/776612D1-573C-49C4-AFF5-23B0FBA48271 2. The user recognizes the limitations of data. Use of the data is at the users' own risk, and there is no warranty as to the quality or accuracy of any data, or the fitness of the data for your intended use. The data are not necessarily fully quality assured and cannot be expected to be free from measurement uncertainty, systematic biases, or errors of interpretation or analysis, and may include inaccuracies in error margins quoted with the data. doi doi crossReference url url crossReference url url dependency url url crossReference url url crossReference textTable eng utf8 geoscientificInformation -103.086 -114.2703 -76.5126 -74.2864 2019-01-29 2019-02-07 It is recommended that careful attention be paid to the contents of any data, and that the author be contacted with any questions regarding appropriate use. If you find any errors or omissions, please report them to polardatacentre@bas.ac.uk. NERC EDS UK Polar Data Centre +44 (0)1223 221400 British Antarctic Survey, High Cross, Madingley Road Cambridge Cambridgeshire CB3 0ET United Kingdom PDCServiceDesk@bas.ac.uk https://www.bas.ac.uk/team/business-teams/information-services/uk-polar-data-centre/ information distributor text/plain bytes 268435456 https://ramadda.data.bas.ac.uk/repository/entry/show?entryid=776612d1-573c-49c4-aff5-23b0fba48271 WWW:LINK-1.0-http--link Get Data Download data download dataset Methodology: PROCESSING: Raw line aeromagnetic data from the 2018/19 ITGC airborne survey were initially corrected for the regional geomagnetic field (IGRF), and compensated for aircraft motion. Compensation coefficients were calculated from a calibration flight flown ~500m above the Lower Thwaites Glacier field camp during the survey. Diurnal variations in the magnetic field were recorded at 30 second intervals using two base stations, one at the Lower Thwaites Glacier field camp, and a second temporary station at the Beamish Drill camp on the Rutford Ice Stream. Base station corrections were calculated by subtracting the local mean base station value across the survey from the recorded base station values. The base station corrections were then filtered with a 30 minute filter to ensure short wavelength signals, likely only seen at the base station, were not transferred to the airborne dataset. The Beamish base station was used to correct the initial input flight and the Lower Thwaites Glacier base station was used to correct all the flights in the main survey area. No base correction was applied to the other transits. An additional Tip Tank correction was made to remove the offsets induced by aircraft operational procedures such as pumping fuel. The tip correction was calculated assuming a linear trend between the DC offset at the start and end of each tip-tank event. This correction is generally restricted to turns and transits, as data quality is worse during these times, and users may wish to consider discarding this data. All the processing has been carried out using Geosoft Oasis Montaj software package. RESOLUTION: The line spacing for the survey is variable between 5 km and 10 km. Line data is generally designed to interleave with existing AGASEA data. The provided data is sampled at 10Hz, which equates to a 6m along track sample spacing. A ~1Hz sinusoidal signal is recognised in the data, and application of 3 second (18 m) low pass filter is therefore recommended. The true usable resolution of this dataset is proportional to the depth to source, which is typically 750 to 1500 m. DATA FORMAT: Data are provided in ASCII file format (.xyz). The aeromagnetic data set includes the following channels: Flight: Sequential survey flight number from T03 to T14. Date: Date YYYY/MM/DD Time_GPS: Time (GPS) HH:MM:SS.SSSSS Lon_deg: Longitude DDD.DDDDDDDD Lat_deg: Latitude DD.DDDDDDDD X: coordinate m Polar stereographic true scale -71 Y: coordinate m Polar stereographic true scale -71 Hght_GRS80: Elevation on the GRS80 ellipsoid RMag: Raw total field magnetic data (nT) XFg_Step: X fluxgate Yfg_Step: Y fluxgate Zfg_step: Z fluxgate MagC: Compensated total field magnetic data (nT) IGRF: IGRF correction (nT) MagRTC: Mag after IGRF, compensation and tip correction (nT) Tcor: Tip correction (nT) Bcor: Base station correction with 30 minute mean filter (nT) MagBRTC: Mag after all corrections (nT) Km: Projected along-track distance (km) Data collection: Data was collected using the BAS aerogeophysicaly equipped twin otter VP-FBL. Magnetic data was collected using wing tip mounted Scintrex CS-3 High Sensitivity Cs magnetometers. Only data from the magnetometer with the lowest noise characteristics is reported here. Data was recorded at 10 Hz on a PicoEnvirotec logging system. Additional base station information from proton procession magnetometers set up as base stations and recording 1 sample every 30 seconds was used during data processing. Data quality: After the basic processing presented here the standard deviation of the crossover errors within the ITGC survey was 16.3 nT. asNeeded completed