3D shear wave (Vsv) velocity model of West Antarctic uppermost mantle structure to 200 km depth

• Main Authors: O'Donnell, John Paul, Stuart, Graham, Brisbourne, Alexander
• Format: Dataset
• Language: English
• Published: UK Polar Data Centre, Natural Environment Research Council, UK Research & Innovation 2019
• Subjects: "EARTH SCIENCE","SOLID EARTH","TECTONICS","EARTHQUAKES","SEISMIC PROFILE","SEISMIC SURFACE WAVES"; Antarctic; Antarctic Peninsula; Austral; West Antarctica; Ellsworth Land; Antarc*; Antarctica
• Online Access: https://dx.doi.org/10.5285/c11bdb27-df44-4b56-8f4c-afc51b6e1e3a; https://data.bas.ac.uk/full-record.php?id=GB/NERC/BAS/PDC/01146

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 UKANET seismic network was deployed in austral summer 2015-2016 and consisted of 10 stations located across the southern Antarctic Peninsula and Ellsworth Land. Each station had a cold-rated Guralp CMG-3T 120 s seismometer sampling at 1 and 100 samples per second. The network was demobilised in austral summer 2017-2018. A detailed description of the earthquake data collection, quality control, processing and analysis are given in: O'Donnell, J. P. et al., 2019. The uppermost mantle seismic velocity structure of West Antarctica from Rayleigh wave tomography: insights into tectonic structure and geothermal heat flow. A detailed description of the ambient noise data collection, quality control, processing and analysis are given in O'Donnell, J. P. et al., 2019. Mapping crustal shear wave velocity structure and radial anisotropy beneath West Antarctica using seismic ambient noise. : The UKANET network used cold-rated Guralp CMG-3T 120 s seismometers sampling at 1 and 100 samples per second combined with Quanterra Q330 digitisers and B44 balers. Resolution: Lateral resolution is variable, depending on the seismic station locations. The 3D shear wave (Vsv) velocity model resolves lateral structure of wavelength 400 km in the uppermost mantle with high fidelity across West Antarctica. : A detailed description of the earthquake data collection, quality control, processing and analysis are given in: O'Donnell, J. P. et al., 2019. The uppermost mantle seismic velocity structure of West Antarctica from Rayleigh wave tomography: insights into tectonic structure and geothermal heat flow. A detailed description of the ambient noise data collection, quality control, processing and analysis are given in O'Donnell, J. P. et al., 2019. Mapping crustal shear wave velocity structure and radial anisotropy beneath West Antarctica using seismic ambient noise.