| Autor: |
WANG Wan-neng, PANG Zhan-ji, WANG Hao-yu, WANG Dong-hui, YU Yi-fan |
| Zdroj: |
Geology & Resources; Dec2023, Vol. 32 Issue 6, p691-698, 8p |
| Abstrakt: |
Bentonites are widely distributed and developed in several layers in the Ordovician-Silurian boundary, which is of great significance for the study of stratigraphic chronology, stratigraphic correlation, event stratigraphy and mass extinction in the penod. The zircon U-Pb dating of bentonites in the bottom of Upper Ordovician-Lower Silurian Longmaxi Formation in Yongshan area on the western margin of Yangtze Plate yields the weighted average age of 443.5± 1.7 Ma, which defines the sedimentary age of the strata and provides a reliable basis for the study of Ordovician-Silurian volcanic eruption event and stratigraphic chronology on the western margin of Yangtze Plate, as well as basic information for the establishment of Ordovician-Silurian high-resolution stratigraphic framework on the periphery of Yangtze Plate. The trace element characteristics of zircon show the features of I-type granite formed in magmatic arc or organic belt. The multi-stage and high-frequency volcanic activity in the Late Ordovician-Early Silurian is possibly the dominant factor causing the mass extinction. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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