Using shear wave splitting measurements to investigate the upper mantle anisotropy beneath the North China Craton: Distinct variation from east to west
Article first published online: 21 MAY 2005
Copyright 2005 by the American Geophysical Union.
Geophysical Research Letters
Volume 32, Issue 10, May 2005
How to Cite
2005), Using shear wave splitting measurements to investigate the upper mantle anisotropy beneath the North China Craton: Distinct variation from east to west, Geophys. Res. Lett., 32, L10309, doi:10.1029/2005GL022585., and (
- Issue published online: 21 MAY 2005
- Article first published online: 21 MAY 2005
- Manuscript Accepted: 20 APR 2005
- Manuscript Revised: 25 MAR 2005
- Manuscript Received: 28 JAN 2005
 A compilation of shear wave splitting measurements in the North China Craton (NCC) is presented to investigate the upper mantle anisotropy beneath the region. By applying the method of Silver and Chan (1991), the splitting parameters of fast polarization direction and delay time are determined from SKS waveforms for 38 broadband stations. The results reveal the presence of small to large seismic anisotropy in the mantle beneath the NCC. The most striking result is the distinct difference of fast polarization directions between the Eastern Block (EB) and the Central Zone (CZ) of the NCC. The fast polarization directions trend SE beneath the EB, which implies that northwestward mantle flow has played a significant role in the reactivating of the EB during Late Mesozoic to Early Cenozoic, and the boundary between the CZ and the EB was possibly a west limit where the mantle flow was deflected. However, a collision event occurred in Early Proterozoic was also a possible cause for the anisotropy of the lithosphere beneath the CZ, depending on the craton lithosphere beneath the region had not been completely reformed by later tectonic activities.