Permo-Triassic intraplate magmatism and rifting in Eurasia: implications for mantle dynamics.
At the transition from the Permian to the Triassic, Eurasia was the site of voluminous flood-basalt extrusion and rifting. Major flood-basalt provinces occur in the Tunguska, Taymyr, Kuznetsk, Verkhoyansk - Vilyuy and Pechora areas, as well as in the South Chinese Emeishen area. Contemporaneous rift...
| Published in: | Tectonophysics |
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| Main Authors: | , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
2002
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| Subjects: | |
| Online Access: | https://research.vu.nl/en/publications/fbf9ecfb-a06b-46a8-8a21-e72ab9b72e7a https://doi.org/10.1016/S0040-1951(02)00123-3 |
| Summary: | At the transition from the Permian to the Triassic, Eurasia was the site of voluminous flood-basalt extrusion and rifting. Major flood-basalt provinces occur in the Tunguska, Taymyr, Kuznetsk, Verkhoyansk - Vilyuy and Pechora areas, as well as in the South Chinese Emeishen area. Contemporaneous rift systems developed in the West Siberian, South Kara Sea and Pyasina Khatanga areas, on the Scythian platform and in the West European and Arctic-North Atlantic domain. At the Permo Triassic transition, major extensional stresses affected apparently Eurasia, and possibly also Pangea, as evidenced by the development of new rift systems. Contemporaneous flood-basalt activity, inducing a global environmental crisis, is interpreted as related to the impingement of major mantle plumes on the base of the Eurasian lithosphere. Moreover, the Permo-Triassic transition coincided with a period of regional uplift and erosion and a low-stand in sea level. Permo Triassic rifting and mantle plume activity occurred together with a major reorganization of plate boundaries and plate kinematics that marked the transition from the assembly of Pangea to its break-up. This plate reorganization was possibly associated with a reorganization of the global mantle convection system. On the base of the geological record, we recognize short-lived and long-lived plumes with a duration of magmatic activity of some 10 - 20 million years and 100-150 million years, respectively. The Permo-Triassic Siberian and Emeishan flood-basalt provinces are good examples of "short-lived" plumes, which contrast with such "long lived" plumes as those of Iceland and Hawaii. The global record indicates that mantle plume activity occurred episodically. Purely empirical considerations indicate that times of major mantle plume activity are associated with periods of global mantle convection reorganization during which thermally driven mantle convection is not fully able to facilitate the necessary heat transfer from the core of the Earth to its surface. In this respect, ... |
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