Shear-wave velocity and attenuation structure beneath Antarctica determined from surface waves

Fundamental and higher mode surface waves generated by nine earthquakes, which occurred in Antarctica and its nearby regions and were recorded at Scott Base (SBA), South Pole (SPA), Novolazarevskaya (NVL) and Mirnyy (MIR) seismic stations are used to determine the shear-wave velocity and attenuation structure beneath these regions. The Frequency-Time Analysis method is used to determine group velocities for periods ranging from 6 to 80 seconds for fundamental and higher mode Rayleigh and Love waves. Crustal thickness is found to be 41 km beneath the eastern part and 30 km beneath the western part of Antarctica. Rayleigh and Love wave group velocities show lower values in the eastern part as compared to the western part of Antarctica. A shear-wave velocity of 3.52 to 3.7 km s- ' is estimated in the lower part of the crust (15-41 km from the surface) beneath eastern Antarctica. Similarly a shear-wave velocity of 3.48-3.6 km s- * is estimated in the lower part of the crust (15-30 km from the surface) beneath western Antarctica. Rayleigh and Love wave group velocities are found to be lower for easter