Seismic evidence links the subducted Mongol-Okhotsk slab to deformation in D″ near the northeastern margin of the Perm Anomaly
作者： Juntao Tao , Jinfeng Hu , Cong Jin , Xiaobo He
DOI: 10.1016/J.TECTO.2019.228297
关键词:
摘要: Abstract Numerical simulations have indicated that the Large low-Shear Velocity Provinces (LLSVPs) dynamically interact with subducted slabs in D″, and turn play an important role influencing shape location of LLSVPs. In this study, we find evidence for existence D” discontinuity near northeastern margin Perm Anomaly — a smaller LLSVP beneath Eurasia, by analyzing Scd (the lower mantle triplication) phases generated from two deep events occurring northwestern Pacific subduction zone recorded at stations Europe Turkey. The D″ north is characterized +2% velocity increase height 300 km above core-mantle boundary (CMB), whereas south +3% 260 km CMB. most likely attributed to phase transition perovskite post-perovskite conjunction presence relic slab materials (likely related Mongol-Okhotsk slab). Our observations– along previous seismic anisotropic detections– provide clue link deformation taking place edges LLSVP.
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sci-hub.se 参考文章(89)
Eh Tan, Wei Leng, Shijie Zhong, Michael Gurnis, On the location of plumes and lateral movement of thermochemical structures with high bulk modulus in the 3‐D compressible mantle Geochemistry Geophysics Geosystems. ,vol. 12, ,(2011) , 10.1029/2011GC003665
Xiaobo He, Maureen D. Long, Lowermost mantle anisotropy beneath the northwestern Pacific: Evidence from PcS, ScS, SKS, and SKKS phases Geochemistry Geophysics Geosystems. ,vol. 12, ,(2011) , 10.1029/2011GC003779
Kenji Kawai, Nozomu Takeuchi, Robert J. Geller, Nobuaki Fuji, Possible evidence for a double crossing phase transition in D″ beneath Central America from inversion of seismic waveforms Geophysical Research Letters. ,vol. 34, ,(2007) , 10.1029/2007GL029642
Michael E. Wysession, Thorne Lay, Justin Revenaugh, Quentin Williams, Edward J. Garnero, Raymond Jeanloz, Louise H. Kellogg, The D″ Discontinuity and its Implications American Geophysical Union (AGU). pp. 273- 297 ,(2013) , 10.1029/GD028P0273
Rob Van der Voo, Wim Spakman, Harmen Bijwaard, Mesozoic subducted slabs under Siberia Nature. ,vol. 397, pp. 246- 249 ,(1999) , 10.1038/16686
Bernhard Steinberger, Trond H. Torsvik, A geodynamic model of plumes from the margins of Large Low Shear Velocity Provinces Geochemistry Geophysics Geosystems. ,vol. 13, ,(2012) , 10.1029/2011GC003808
Scott W. French, Barbara Romanowicz, Broad plumes rooted at the base of the Earth's mantle beneath major hotspots Nature. ,vol. 525, pp. 95- 99 ,(2015) , 10.1038/NATURE14876
Eh Tan, Michael Gurnis, Lijie Han, Slabs in the lower mantle and their modulation of plume formation Geochemistry Geophysics Geosystems. ,vol. 3, pp. 1- 24 ,(2002) , 10.1029/2001GC000238
Lauren Waszek, Christine Thomas, Arwen Deuss, PKP precursors : Implications for global scatterers Geophysical Research Letters. ,vol. 42, pp. 3829- 3838 ,(2015) , 10.1002/2015GL063869
Yao Yao, Stefanie Whittaker, Michael S. Thorne, D″ discontinuity structure beneath the North Atlantic from Scd observations Geophysical Research Letters. ,vol. 42, pp. 3793- 3801 ,(2015) , 10.1002/2015GL063989