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West Antarctica

21 record(s)
 
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  • 3D vertically-polarised shear wave (Vsv) velocity model of West Antarctic crustal structure developed using data from the 2016-2018 UK Antarctic Seismic Network (UKANET) and Polar Earth Observing Seismic Network (POLENET). Interstation Rayleigh and Love wave phase velocity dispersion measurements at periods of 8-25 seconds were extracted from seismic ambient noise cross-correlograms by automated frequency-time analysis (AFTAN). The ensemble of interstation Rayleigh wave dispersion measurements was used to develop 2D Rayleigh wave phase velocity maps of West Antarctica at periods of 8-25 seconds by Fast Marching Surface Tomography (FMST) on a grid with a node spacing of 0.75deg. 'Local' 1D Rayleigh wave phase velocity dispersion curves were extracted by sampling the 2D Rayleigh wave phase velocity maps at grid node locations. The local 1D Rayleigh wave phase velocity dispersion curves were inverted for 1D shear wave (Vsv) structure to 40 km depth, and the ensemble of 1D shear wave (Vsv) profiles were subsequently gridded to produce the 3D shear wave (Vsv) model of West Antarctica from 10-40 km depth. Funding was provided by the NERC standard grant NE/L006065/1.

  • 3D vertically-polarised shear wave (Vsv) velocity model of West Antarctic uppermost mantle structure to 200 km depth developed using data from the 2016-2018 UK Antarctic Seismic Network (UKANET) and Polar Earth Observing Seismic Network (POLENET). The model was constructed from the combination of fundamental mode Rayleigh wave phase velocity maps developed by ambient noise (periods 8-25 seconds) and earthquake data two-plane wave analysis (periods 20-143 seconds). Composite 'local' 1D Rayleigh wave phase velocity dispersion curves (periods 8-143 s) were extracted by sampling the 2D Rayleigh wave phase velocity maps at grid node locations spanning West Antarctica spaced at 100 km. The local 1D Rayleigh wave phase velocity dispersion curves were inverted for 1D shear wave (Vsv) structure to 200 km depth, and the ensemble of 1D shear wave (Vsv) profiles were subsequently gridded to produce the 3D shear wave (Vsv) model of West Antarctica uppermost mantle structure to 200 km depth. Funding was provided by the NERC standard grant NE/L006065/1.

  • The dataset presented here contains a csv-file including the coordinates, received power of the bed reflection and the two-way travel time of the bed reflection. The X and Y coordinates are projected in EPSG:3031 - WGS 84 / Antarctic Polar Stereographic coordinate system. Data presented here have been frequency filtered and 2D migrated (using a finite difference approach and migration velocity of 0.168 m ns-1), followed by the picking of the bed reflection using ReflexW software (Sandmeier Scientific Software). The received power is calculated within a 280 ns time window centred on, and encompassing, the bed reflection (Gades et al., 2000). This work was funded within the BEAMISH project by NERC AFI award numbers NE/G014159/1 and NE/G013187/1.

  • This dataset contains ASCII files with hypocenter information, event times and magnitudes for 227029 micro-earthquakes with a magnitude range from -2.0 to -0.3 recorded from a 35-station seismic network located ~40 km upstream of the grounding line of Rutford Ice Stream, West Antarctica. For 87910 of these events, earthquake focal mechanisms (strike/dip/rake) are available. The seismic network, which recordings are the base for the event catalogue, broadly formed a rectangle with 1 km station spacing. Details on the station locations, instrument types and operation periods are included in these data files. The event catalogue encloses the geographic region between 084.142 to 083.760 degrees West and 78.204 to 78.113 degrees South. Events are located between 1.553 and 2.416 km depth. Recording took place between 20th November 2018 and 16th February 2019. The spatio-temporal arrangement of these micro-earthquakes can be used to characterize frictional properties at the ice-bed interface of Rutford Ice Stream. This work was funded within the BEAMISH project by NERC AFI award numbers NE/G014159/1 and NE/G013187/1. Seismic instruments were provided by NERC SEIS-UK (Loan 1017) and the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center at New Mexico Tech.

  • The dataset presented here focuses on the area of a prominent bedform beneath the Rutford Ice Stream, referred to as "the Bump". The provided dataset contains several CSV files including the coordinates, two-way travel time of the bed reflection, the reflectivity of the bed reflection and acoustic impedance of the bed reflection, respectively. The X and Y coordinates are projected in EPSG:3031 - WGS 84 / Antarctic Polar Stereographic coordinate system. Radar topography presented here were frequency filtered and 3D migrated (using a 3D Kirchhoff Time Migration approach in SeisSpace/ProMAX (LGCHalliburton Software) and migration velocity of 0.168 m ns-1), followed by the picking of the bed reflection using Petrel (Schlumberger Software). Radar reflectivity was calculated from 2D migrated radar data following the processing routine as described in Schlegel et al. (2022) including frequency filtering and 2D migration in SeisSpace/ProMAX. Seismic acoustic impedance of the bed reflection was calculated following Smith et al. (2007). This work was funded within the BEAMISH project by NERC AFI award numbers NE/G014159/1 and NE/G013187/1 and NE/F015879/1, and by NERC National Capability Science: Strategic Research & Innovation Short Projects. The University of Leeds acknowledges the support of this work by Landmark Software and Services, a Landmark Company and use of SeisSpace/ProMAX via the Landmark University Grant Program, Agreements 2004-COM-024982, 2008-CON-010888 and subsequent renewals.

  • Dual-frequency GPS data from a single receiver installed on the surface of Rutford Ice Stream in West Antarctica. The instrument was operated from late 2004 to early 2007. Gaps in the data set occur, through periods of power loss in the winters and during station relocations. Funding was provided by NERC Antarctic Funding Initiative (AFI) GR3/G005, NERC under the British Antarctic Survey National Capability programme, Polar Science for Planet Earth, Leverhulme Trust Fellowship (to T Murray), and RCUK Academic Fellowship (to M A King).

  • High-resolution simulation of summer climate over West Antarctica using the Polar-optimised version of the Weather Research and Forecasting (WRF) model conducted at British Antarctic Survey, Cambridge, UK. Runs are conducted for summer (January-centred) 1980-2015, i.e. from December 1979 to February 2015, for December, January and February (DJF). Experiments were carried out for the NERC West Antarctic Grant (NE/K00445X/1) during 2014-2017. The project is aimed at understanding the variability and climatology over the West Antarctic ice sheet and ice shelves as well as to project the future change over the twenty-first century. The model outer domain encompasses the West Antarctic ice sheet and a large part of the surrounding ocean at 45 km horizontal grid spacing, and the nested (one-way) inner domain covers the Amundsen Sea Embayment at 15 km grid spacing. The model uses vertical eta coordinates with both domains have a model top of 50 hPa, and 30 vertical levels.

  • Borehole temperature measurements from the upper 300 m of Rutford Ice Stream. A string of thermistors was installed into a hot-water drilled hole in February 2005. The string comprised 10 calibrated thermistors at approximately 30 m spacing. The temperature measurements provided were taken in February 2007, following ample time for the heat from the drilling process to have dissipated.

  • This dataset contains locations and orientations of striations observed on bedrock surfaces in the Hudson Mountains, West Antarctica. These were collected in December 2019 by Joanne S Johnson during a British Antarctic Survey-supported geological field campaign, as part of the International Thwaites Glacier Collaboration (funded by NERC and NSF). Funding: NERC grant: NE/S006710/1

  • This dataset contains geomorphological data (measurements of size, shape, long axis orientation and weathering characteristics) on 90 erratic cobbles collected from the Hudson Mountains in West Antarctica. These were collected during three field campaigns, as follows: 1) 75 erratic cobbles collected by Joanne S Johnson during a British Antarctic Survey-supported geological field campaign undertaken in November-December 2019, as part of the International Thwaites Glacier Collaboration (funded by NERC and NSF). 2) 13 cobbles collected by James A Smith (British Antarctic Survey) in February and March 2010 during RV Polarstern cruise ANT XXVI/3, and 3) a further two cobbles collected in March 2006 by Johnson during RV Polarstern cruise ANT XXIII/4. These cobbles were all collected for surface exposure dating. Funding: NERC grant: NE/S006710/1