S-velocity model and inferred Moho topography beneath the Antarctic Plate from Rayleigh waves

Since 2007/2008, seismographs were deployed in many new locations across much of Antarctica. Using the records from 122 broadband seismic stations, over 10,000 Rayleigh wave fundamental‐mode dispersion curves have been retrieved from earthquake waveforms and from ambient noise. Using the processed d...

Full description

Saved in:
Bibliographic Details
Published in:Journal of Geophysical Research 2015-01, Vol.120 (1), p.359-383
Main Authors: An, Meijian, Wiens, Douglas A., Zhao, Yue, Feng, Mei, Nyblade, Andrew A., Kanao, Masaki, Li, Yuansheng, Maggi, Alessia, Lévêque, Jean-Jacques
Format: Article
Language:English
Subjects:
Age
Ambient noise
Antarctica
Banks (topography)
Belts
Broadband
Buoyancy
Continental crust
crust
Crustal thickness
Crusts
Density
Density ratio
Depth
Dispersion
Earth Sciences
Earthquake construction
Earthquakes
Geological time
Geophysics
Gondwana
High resolution
International Polar Year
Lithosphere
Locations (working)
Magma
Mantle
Mathematical models
Methods
Moho
Mountains
Noise prediction
Orogeny
Plates (tectonics)
Rayleigh waves
Records
Sciences of the Universe
Seismic activity
Seismographs
Slope
Surface water waves
Three dimensional models
tomography
Topography
Topography (geology)
Velocity
Wave dispersion
Waveforms
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Since 2007/2008, seismographs were deployed in many new locations across much of Antarctica. Using the records from 122 broadband seismic stations, over 10,000 Rayleigh wave fundamental‐mode dispersion curves have been retrieved from earthquake waveforms and from ambient noise. Using the processed data set, a 3‐D S‐velocity model for the Antarctic lithosphere was constructed using a single‐step surface wave tomographic method, and a Moho depth map was estimated from the model. Using the derived crustal thicknesses, the average ratio of lithospheric mantle and crustal densities of Antarctica was calculated. The calculated density ratio indicates that the average crustal density for Antarctica is much higher than the average values for continental crust or the average density of lithospheric mantle is so low as to be equal to low‐density bound of Archean lithosphere. The latter implies that the lithospheric mantle in much of Antarctica should be old and of Archean age. The East Antarctic Mountain Ranges (EAMOR) represent a thick crustal belt, with the thickest crust (~60 km) located close to Dome A. Very high velocities can be found at depths greater than 200 km beneath parts of East Antarctica, demonstrating that the continental lithosphere extends deeper than 200 km. The very thick crust beneath the EAMOR may represent the collision suture of East Gondwana with Indo‐Antarctica and West Gondwana during the Pan‐African orogeny. Key Points High‐resolution crust/lithosphere Vs model covering the whole Antarctic Plate Lithospheric mantle in most of the Antarctica is significantly old and buoyant East Antarctic Mountain Ranges are a thick‐crust belt
ISSN:2169-9313
0148-0227
2169-9356
2156-2202
DOI:10.1002/2014JB011332