Seismicity of the Antarctica Great Wall Station Area in 2019
This paper developed a single station location method with interleaved grid search,based on the broadband three-component continuous waveform data recorded in 2019 at the Antarctic Great Wall Seismic Station,which completed its reconstruction during the 35th Antarctic Scientific Expedition of China.The single station location method was conducted and applied to seismic location studies in the Great Wall Station area,resulting in the location of 35 local seismic events with high signal-to-noise ratios and the generation of distribution map of events in 2019 in the South Shetland Islands region.The results show that the events are predominantly distributed along the NE-trending South Shetland Islands.The maximum magnitude is ML4.4,while the minimum magnitude is ML1.6,with the focal depth range of 12～115 km.The analysis of the seismicity in the region reveals that the seismicity in the South Shetland Islands,where the Great Wall Station is located,is stronger than that in the stable Antarctic continent.This is mainly due to the region's direct or indirect influence from the Antarctic Plate,the South American Plate and the Scotia Plate.Some intermediate-depth earthquakes are distributed in the southern part of the South Shetland Islands and the fore-arc basin near the South Shetland Trench on its west side,indicating that the region is affected by plate subduction.This directly gives the seismological evidence that the subduction of the Phoenix Plate beneath the South Shetland Islands is still ongoing.The Bransfield Strait is situated within the back-arc basin of the South Shetland Islands Arc.The region continues to expand in NW-SE direction,exhibiting notable volcanic activity and magmatic hydrothermal movement.It is postulated that the seismicity in the region is associated with volcanic activity.
Antarctic Great Wall Seismic StationEarthquake locationSeismicityPlate subductingVolcanic activity
万方数据
维普
