Jurassic picritic and potassic mafic dyke swarms in eastern China: Evidence for thermal erosion of the lithospheric mantle during Paleo-Pacific subduction

Wang, Wenjia; Song, Shuguang; Wang, Chao; Allen, Mark B.; Zhang, Lifei; Li, Xiaowei; Su, Li

doi:10.1016/j.gr.2025.02.012

Jurassic picritic and potassic mafic dyke swarms in eastern China: Evidence for thermal erosion of the lithospheric mantle during Paleo-Pacific subduction

Wang, Wenjia; Song, Shuguang; Wang, Chao; Allen, Mark B.; Zhang, Lifei; Li, Xiaowei; Su, Li

Authors

Wenjia Wang

Shuguang Song

Chao Wang

Professor Mark Allen m.b.allen@durham.ac.uk
Professor

Lifei Zhang

Xiaowei Li

Li Su

Abstract

Paleo-Pacific subduction significantly impacted the structure and nature of the mantle in Eastern China. However, the thermal structure of the supra-subduction-zone mantle during the early stage of the Paleo-Pacific subduction has not been well constrained. Here, we present an integrated study involving field investigation, petrology, and geochemistry on two types of Jurassic (168–155 Ma) mafic dyke swarms in Western Liaoning, North China Craton (NCC), to trace the properties of the NCC mantle during the Jurassic. The picritic dyke swarms, trending NNW (330°–350°), show OIB-like geochemical signatures, with high mantle potential temperatures (Tp) ranging from 1498 ± 52°C to 1535 ± 56°C. These picritic dyke swarms are derived from high-degree of partial melting of the asthenospheric mantle by a hot and hydrous asthenospheric melts rising from the mantle transition zone above the subducted slab. In contrast, the Jurassic potassic mafic dyke swarms, trending NNW (325°–345°), were formed by partial melting of the metasomatized lithospheric mantle during the upwelling of the asthenospheric melts. We conclude that thermal erosion would be a major factor in the destruction of the lithospheric mantle beneath the NCC in the early stage of the Paleo-Pacific plate subduction.

Citation

Wang, W., Song, S., Wang, C., Allen, M. B., Zhang, L., Li, X., & Su, L. (2025). Jurassic picritic and potassic mafic dyke swarms in eastern China: Evidence for thermal erosion of the lithospheric mantle during Paleo-Pacific subduction. Gondwana Research, 141, https://doi.org/10.1016/j.gr.2025.02.012

Journal Article Type	Article
Acceptance Date	Feb 24, 2025
Online Publication Date	Feb 26, 2025
Publication Date	2025-05
Deposit Date	Feb 27, 2025
Publicly Available Date	Feb 28, 2025
Journal	Gondwana Research
Print ISSN	1342-937X
Publisher	Elsevier
Peer Reviewed	Peer Reviewed
Volume	141
DOI	https://doi.org/10.1016/j.gr.2025.02.012
Public URL	https://durham-repository.worktribe.com/output/3550387