EGU2020-1467
https://doi.org/10.5194/egusphere-egu2020-1467
EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

A subducted slab of the Paleo-Tethys oceanic lithosphere associated with the formation of the Emeishan large igneous province

Chuansong He
Chuansong He
  • Institute of Geophysics, CEA, Beijing, China (hechuansong@aliyun.com)

The formation of large igneous provinces is a focus of geoscientists and is a major scientific issue in mantle dynamics. A broad consensus holds that the Emeishan large igneous province (ELIP) was generated by an upwelling mantle plume. However, recent geological and seismic studies have challenged this notion. In this study, I redraw and reanalyze previous tomographic images and use images of three velocity perturbation profiles crossing the ELIP. I collected abundant high-quality teleseismic data and performed common conversion point (CCP) stacking of receiver functions in the mantle transition zone (MTZ) of the ELIP. The tomographic images show a high-velocity anomaly of a northeastward-subducted slab-like body beneath the ELIP, which might be a relic of the Paleo-Tethys oceanic lithosphere. Images from CCP stacking of receiver functions indicate that the subducted slab of the Paleo-Tethys oceanic lithosphere retained an imprint on the X-discontinuity and the 410 and 660 km discontinuities. Based on my assessment, the subducted slab might have induced return mantle flow or large-scale mantle upwelling, which possibly played an important role in the formation of the ELIP.

How to cite: He, C.: A subducted slab of the Paleo-Tethys oceanic lithosphere associated with the formation of the Emeishan large igneous province, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1467, https://doi.org/10.5194/egusphere-egu2020-1467, 2019