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Weak and vanishing upper mantle discontinuities generated by large-scale lithospheric delamination in the Longmenshan area, China.

ABSTRACT: A large amount of high-quality teleseismic data is used for common conversion point (CCP) stacking of receiver functions in the Longmenshan area and near-by region. The results show that a large-scale high-velocity anomaly (LHVA) or lithospheric delamination can modify the structure of upper mantle discontinuities or weaken the phase boundary of olivine, which is a very important finding and can be used to assess stagnant slabs in the mantle transition zone globally. The deepening region of the 660 km discontinuity beneath the Songpan-Ganzi terrane identified in this study might be generated by the LHVA.

SUBMITTER: He C

PROVIDER: S-EPMC8566558 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Weak and vanishing upper mantle discontinuities generated by large-scale lithospheric delamination in the Longmenshan area, China.

He Chuansong C

Scientific reports 20211103 1

A large amount of high-quality teleseismic data is used for common conversion point (CCP) stacking of receiver functions in the Longmenshan area and near-by region. The results show that a large-scale high-velocity anomaly (LHVA) or lithospheric delamination can modify the structure of upper mantle discontinuities or weaken the phase boundary of olivine, which is a very important finding and can be used to assess stagnant slabs in the mantle transition zone globally. The deepening region of the ...[more]

PMID: 34732789

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