DOI: 10.1002/2015GL066036
论文题名: Evidence of Middle Jurassic magmatism within the Seychelles microcontinent: Implications for the breakup of Gondwana
作者: Shellnutt J.G. ; Lee T.-Y. ; Chiu H.-Y. ; Lee Y.-H. ; Wong J.
刊名: Geophysical Research Letters
ISSN: 0094-8362
EISSN: 1944-8093
出版年: 2015
卷: 42, 期: 23 起始页码: 10207
结束页码: 10215
语种: 英语
英文关键词: Callovian
; Gondwana
; Hf Isotopes
; Seychelles
; Tithonian
; U/Pb dating
Scopus关键词: Igneous rocks
; Isotopes
; Lead
; Silicate minerals
; Tectonics
; Callovian
; Gondwana
; Hf isotope
; Seychelles
; Tithonian
; Hafnium
英文摘要: 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. © 2015. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84953432800&doi=10.1002%2f2015GL066036&partnerID=40&md5=5168757f78af57de350eccf889b7645b
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/7978
Appears in Collections: 科学计划与规划 气候变化与战略
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作者单位: Department of Earth Sciences, National Taiwan Normal University, Taipei, Taiwan
Recommended Citation:
Shellnutt J.G.,Lee T.-Y.,Chiu H.-Y.,et al. Evidence of Middle Jurassic magmatism within the Seychelles microcontinent: Implications for the breakup of Gondwana[J]. Geophysical Research Letters,2015-01-01,42(23).