Is There an Interconnected Lower Crustal Channel Flow beneath Southeastern Margin of Tibetan Plateau? 青藏高原东南缘存在连通的下地壳流吗?

Ning，Shuoxian1; Chen，Yongshun1,2

2023-05-20

10.13209/j.0479-8023.2023.018

Beijing Daxue Xuebao (Ziran Kexue Ban)/Acta Scientiarum Naturalium Universitatis Pekinensis   Impact Factor & Quartile

0479-8023

A 3-D shear wave velocity model of Southeastern Margin of Tibetan Plateau crust was constructed by Markov Chain Monte Carlo inversion, based on Rayleigh wave phase velocity tomography results which are obtained from ambient noise interferometry and tele-seismic two plane wave analysis, using seismic data of 137 permanent stations from China digital seismic network and 332 portable stations from ChinArray. The velocity model indicates the presence of an interconnected lower crustal channel flow in southeastern margin of Tibetan plateau, which is represented by an interconnected low shear wave velocity zone with V < 3.55 km/s. It consists of three parts which respectively locates beneath the Panzhihua area and to its west and east. The lower crustal channel flow from Tibetan Plateau is blocked by rigid lower crust of the Sichuan block and turns to flow through Emeishan area to the south direction, which alters the lower crust of Emeishan large igneous province (ELIP) together with the lower crustal channel flow beneath Pahzhihua area, thickening the crust in this area. It is infered that the lower crustal channel flow beneath the southeast margin of Tibetan Plateau ends at about 24°N, and has the potential to extend further south, which has the role to extend the scope of crustal thickening in the future.

crustal channel flow Emeishan Large Igneous Province surface wave tomography Tibetan Plateau

Chinese

Corresponding

2-s2.0-85163390506

Scopus

1.School of Earth and Space Sciences,Peking University,Beijing,100871,China
2.Department of Ocean Science and Engineering,South University of Science and Technology,Shenzhen,518055,China

Ning，Shuoxian,Chen，Yongshun. Is There an Interconnected Lower Crustal Channel Flow beneath Southeastern Margin of Tibetan Plateau? 青藏高原东南缘存在连通的下地壳流吗?[J]. Beijing Daxue Xuebao (Ziran Kexue Ban)/Acta Scientiarum Naturalium Universitatis Pekinensis,2023,59(3):395-406.

Ning，Shuoxian,&Chen，Yongshun.(2023).Is There an Interconnected Lower Crustal Channel Flow beneath Southeastern Margin of Tibetan Plateau? 青藏高原东南缘存在连通的下地壳流吗?.Beijing Daxue Xuebao (Ziran Kexue Ban)/Acta Scientiarum Naturalium Universitatis Pekinensis,59(3),395-406.

Ning，Shuoxian,et al."Is There an Interconnected Lower Crustal Channel Flow beneath Southeastern Margin of Tibetan Plateau? 青藏高原东南缘存在连通的下地壳流吗?".Beijing Daxue Xuebao (Ziran Kexue Ban)/Acta Scientiarum Naturalium Universitatis Pekinensis 59.3(2023):395-406.