Evidence of Middle Jurassic magmatism within the Seychelles microcontinent: Implications for the breakup of Gondwana

J. G. Shellnutt*, T. Y. Lee, H. Y. Chiu, Y. H. Lee, J. Wong

*此作品的通信作者

研究成果: 雜誌貢獻期刊論文同行評審

5 引文 斯高帕斯(Scopus)

摘要

The breakup of East and West Gondwana occurred during the Jurassic, but the exact timing is uncertain due to the limited exposure of rocks suitable for radioisotopic dating. Trachytic rocks from Silhouette Island, Seychelles, yielded a range of zircon ages from Paleoproterozoic to Cenozoic. The 206Pb/238U age of the trachyte is 64.9 ± 1.6 Ma (Danian) but the majority of zircons yielded an age of 163.8 ± 1.8 Ma (Callovian) with a small subset yielding an age of 147.7 ± 4.5 Ma (Tithonian). The Hf isotopes of the Callovian (εHf(t) = +4.1 to +13.4) and Danian (εHf(t) = +1.9 to +7.1) zircons indicate that they were derived from moderately depleted mantle sources whereas the Tithonian zircons (εHf(t) = -7.0 to -7.3) were derived from an enriched source. The identification of middle Jurassic zircons indicates that rifting and magmatism were likely contemporaneous during the initial separation of East and West Gondwana.

原文英語
頁(從 - 到)10207-10215
頁數9
期刊Geophysical Research Letters
42
發行號23
DOIs
出版狀態已發佈 - 2015 十二月 16

ASJC Scopus subject areas

  • 地球物理
  • 地球與行星科學(全部)

指紋

深入研究「Evidence of Middle Jurassic magmatism within the Seychelles microcontinent: Implications for the breakup of Gondwana」主題。共同形成了獨特的指紋。

引用此