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  • A British Antarctic Survey Twin Otter and survey team acquired 8,300 line-km of aerogeophysics data during the Austral summer of 1998/99. Gravity and radio-echo data were acquired simultaneously with the magnetic data at a compromise constant barometric height of 2,200 m, which provides a terrain clearance of 100 m over the highest peaks. Two separate surveys were conducted; one at 5 km line spacing (tie lines at 20 km) over and stretching beyond the southern extent of the Forrestal range (main survey), and one at 2 km line spacing (tie lines at 8 km) covering the Dufek Massif (detailed survey). Ashtech Z12 dual frequency GPS receivers were used for survey navigation. Pseudorange data were supplied to a Picodas PNAV navigation interface computer, which was used to guide the pilot along the pre-planned survey lines. The actual flight path was recovered, using carrier-phase, continuous, kinematic GPS processing techniques. All pseudorange navigation data were recorded at 1 Hz on a Picodas PDAS 1000, PC-based data acquisition system. We present here the processed line aerogravity data collected using Lacoste and Romberg air-sea gravity meter S83. Data are provided as XYZ ASCII line data.

  • The survey collected a total of 11,500 km of data along 22 lines, spaced 12 km apart and oriented perpendicular to the strike of both the Bouguer anomaly field, as derived from land data (McGibbon and Smith, 1991), and the major sub-ice topographical features (Doake et al., 1983). The speed of the aircraft was set to produce a sample spacing of about 60 m and the data were collected at heights between 1600 and 2000 m above sea level. The gravity signal was recorded using a LaCoste and Romberg air/sea gravimeter, S-83, which has been kindly loaned to BAS by the Hydrographic Office of the Royal Navy. The meter was modified by the ZLS company for use in an aircraft. The equipment was deployed in a BAS De-Havilland Twin Otter aircraft. Differential, dual frequency, carrier phase, GPS measurements of the aircraft''s motion were made using Trimble and Ashtech geodetic receivers and antennas. Ice thickness data were obtained using a BAS-built, radio echo sounding system (Corr and Popple, 1994). Ice-bottom returns over most of the survey area were obtained at a sample spacing of approximately 28 m. GPS measurements were tied into base stations in International Terrain Reference Frame network (Dietrich et al., 1998) and gravity measurements to base stations in the IGSN71 net (Jones and Ferris, 1999). We present here the processed line aerogravity data collected using Lacoste and Romberg air-sea gravity meter S83. Data are provided as XYZ ASCII line data.

  • This data set contains aerogravity data collected during the WISE/ISODYN project. This collaborative UK/Italian project collected ~ 61000 line km of new aerogeophysical data during the 2005/2006 austral summer, over the previously poorly surveyed Wilkes subglacial basin, Dome C, George V Land and Northern Victoria Land. We present here the processed line aerogravity data collected using a LaCoste & Romberg air-sea gravity meter S83 mounted in the BAS aerogeophysically equipped Twin Otter aircraft. Data are provided as XYZ ASCII line data.

  • During the 1996-1997 Antarctic field season, an aeromagnetic survey was carried out by the BAS to the west of Alexander Island, designed to investigate the Charcot Island anomaly. The presented data was collected using wingtip mounted Caesium-vapour magnetometers. Magnetic effects due to aircraft motion were actively compensated using a triad of fluxgate magnetometers mounted in the tail of the aircraft. Data are provided as XYZ ASCII line data.

  • Airborne gravity data were collected using a Zero Length Spring Corporation (ZLS)-modified LaCoste and Romberg model S air-sea gravimeter. The meter was mounted in a gyro-stabilised, shock mounted platform at the centre of mass of the aircraft to minimise the effect of vibrations and rotational motions. GPS data were recorded with an Ashtech Z12 dual frequency receiver in the aircraft and at a fixed base station. Differential, carrier phase, kinematic GPS methods were then used to calculate all the navigational information used for the dynamic corrections of the aerogravity data. Standard processing steps were taken to convert the raw gravity data to free air anomalies, including latitude, free air and Eotvos corrections. The vertical accelerations of the aircraft, which dominate the gravity signal recorded by the meter, were calculated by double differencing GPS height measurements. In addition, a correction was made for gravimeter reading errors caused by the platform tilting when it was subjected to horizontal accelerations (Swain, 1996). After making the above corrections, the data were low pass filtered for wavelengths less than 9 km to remove short wavelength noise from the geological signal. The data were continued to a common altitude of 2050 m and levelled. Cross-over analysis at 118 intersections yielded a standard deviation of 2.9 mGal, which is within the 1-5 mGal error range typically reported for airborne gravity surveys after levelling. Comparison between airborne measurements and previous land-based gravity data (Garrett, 1990), yielded an RMS difference of ~4.5 mGal, which is within the 2 sigma range for airborne gravity data accuracy.

  • The ESA PolarGap airborne gravity, lidar/radar and aeromagnetic survey was carried out in Antarctica in the field season 2015/16. The purpose of the 2015/16 ESA PolarGAP airborne survey of the South Pole region was to fill the gap in satellite gravity coverage, enabling construction of accurate global geoid models. Additional radar flights over the Recovery Lakes for the Norwegian Polar Institute (NPI) were carried out as part of the same survey, but included collection of airborne gravity. Gravity data were collected using two complimentary systems. The primary system was a ZLS-modified Lacoste and Romberg (LCR) gravimeter (S-83) which gives exceptionally low and predictable long term drift. The secondary system was high specification inertial navigation system (iMAR RQH-1003), provided by TU Darmstadt, capable of resolving gravity anomalies even under turbulent conditions, but more prone to instrument drift. Results from both systems were merged to give a unified best product. The aircraft used was the BAS aerogeophysicaly equipped twin otter VP-FBL. Data are available as an ASCII table (.csv).

  • Over 20,000 km of new aeromagnetic data were acquired over Palmer Land during the 2002-2003 Antarctic campaign. Profile lines were oriented E-W with N-S tie lines. Line spacing was 5 km, tie lines were 25 km apart and nominal flight altitude was 2800 m. Aeromagnetic processing included magnetic compensation, IGRF removal, diurnal correction, and levelling. Mean cross-over errors after microlevelling were <1 nT. Aeromagnetic data were gridded (1 km cell size) and reduced to the pole. We present here the processed line aeromagnetic data acquired using scintrex cesium magnetometers mounted on the BAS aerogeophysical equiped Twin Otter. Data are provided as XYZ ASCII line data.

  • Three separate airborne radar surveys were flown during the austral summer of 2016/17 over the Filchner Ice Shelf and Halley Ice Shelf (West Antarctica), and over the outlet glacier flows of the English Coast (western Palmer Land, Antarctic Peninsula) during the Filchner Ice Shelf System (FISS) project. This project was a NERC-funded (grant reference number: NE/L013770/1) collaborative initiative between the British Antarctic Survey, the National Oceanography Centre, the Met Office Hadley Centre, University College London, the University of Exeter, Oxford University, and the Alfred Wenger Institute to investigate how the Filchner Ice Shelf might respond to a warmer world, and what the impact of sea-level rise could be by the middle of this century. The 2016/17 aerogeophysics surveys acquired a total of ~26,000 line km of aerogeophysical data. The FISS survey consisted of 17 survey flights totalling ~16,000 km of radar data over the Support Force, Recovery, Slessor, and Bailey ice streams of the Filchner Ice Shelf. The Halley Ice Shelf survey consisted of ~4,600 km spread over 5 flights and covering the area around the BAS Halley 6 station and the Brunt Ice Shelf. The English Coast survey consisted of ~5,000 km spread over 7 flights departing from the Sky Blu basecamp and linking several outlet glacier flows and the grounding line of the western Palmer Land, including the ENVISAT, CRYOSAT, GRACE, Landsat, Sentinel, ERS, Hall, Nikitin and Lidke ice streams. Our Twin Otter aircraft was equipped with dual-frequency carrier-phase GPS for navigation, radar altimeter for surface mapping, wing-tip magnetometers, an iMAR strapdown gravity system, and a new ice-sounding radar system (PASIN-2). We present here the processed line aerogravity data collected using the iMAR strapdown gravity system mounted in the BAS aerogeophysically equiped Twin Otter aircraft. Data are provided as XYZ ASCII line data.

  • Using the British Antarctic Survey''s DeHavilland Dash-7, approximately 10,000 line-km of data were collected from the Black Coast and adjacent Weddell Sea embayment, which is situated ca. 600 km southeast of the airfield at Rothera Station . Flight lines were spaced at 10-km intervals with perpendicular tie lines spaced at 40 km. Where time and fuel allowed, selected areas were infilled at a 5-km line spacing. The marine part of the survey was flown at around less than 1000 m above sea level.We present here the processed line aeromagnetic data acquired using scintrex cesium magnetometers mounted on the BAS aerogeophysical equiped Dash-7. Data are provided as XYZ ASCII line data.

  • The ESA PolarGap airborne gravity, lidar/radar and aeromagnetic survey was carried out in Antarctica in the field season 2015/16. The purpose of the 2015/16 ESA PolarGAP airborne survey of the South Pole region was to fill the gap in satellite gravity coverage, enabling construction of accurate global geoid models. Additional radar flights over the Recovery Lakes for the Norwegian Polar Institute (NPI) were carried out as part of the same survey. In conjunction with the primary datasets aeromagnetic data was collected opportunistically, to provide new insights into the subglacial geology. 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 (http://admap.kopri.re.kr/ADMAP-2_SCR_27Aug13.pdf). The aircraft used was the BAS aerogeophysicaly equipped twin otter VP-FBL. Data are available as an ASCII table (.csv).