globalchange  > 气候变化与战略
DOI: 10.1016/j.epsl.2020.116090
论文题名:
Chemical evolution of the continental crust from a data-driven inversion of terrigenous sediment compositions
作者: Ptáček M.P.; Dauphas N.; Greber N.D.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2020
卷: 539
语种: 英语
中文关键词: Archaean geochemistry ; continental composition ; crustal geotherm ; plate tectonics
英文关键词: Geothermal energy ; Markov chains ; Trace elements ; Continental crusts ; Elemental concentrations ; Geothermal gradients ; Local Outlier Factor ; Markov chain monte carlo algorithms ; Sediment provenance ; Terrigenous sediment ; Upper continental crust ; Sediments ; algorithm ; Archean ; chemical composition ; concentration (composition) ; continental crust ; data inversion ; geothermal gradient ; terrigenous deposit
英文摘要: The nature of emerged continents through time is highly debated. Several studies relying on trace element data concluded that the Archaean crust was predominantly mafic, while Ti isotope systematics point to an Archaean crust that was predominantly felsic. Here, we resolve the inconsistency between these two approaches by applying a novel statistical method to a compilation of published elemental concentrations in terrigenous sediments (the OrTeS database). We use a filter based on the Local Outlier Factor to reject sediment samples that have been affected by alteration processes or mineral fractionation during transport. The nature of the emerged continents is calculated using an inverse mixing model based on a Markov Chain Monte Carlo algorithm. A procedure is presented to automatically select elemental ratios that are best suited for constraining the sediment provenance. We find that for all systems that accurately reconstruct the modern-day composition of the continents, a continuous >50% felsic contribution is required to explain the composition of fine-grained terrigenous sediments starting from 3.5 billion years ago. This finding is consistent with an early onset of plate tectonics. We estimate the geothermal gradient in the Archaean upper continental crust by tracking the reconstructed concentrations of the radiogenic heat-producing elements K, U, and Th through time. Radioactive heat production in the bulk continental crust was 50% higher in the Archaean compared to the present, resulting in a continental geothermal gradient that was about 40% higher. © 2020
Citation statistics:
被引频次[WOS]:37   [查看WOS记录]     [查看WOS中相关记录]
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/165221
Appears in Collections:气候变化与战略

Files in This Item:

There are no files associated with this item.


作者单位: Origins Laboratory, Department of the Geophysical Sciences, Enrico Fermi Institute, The University of Chicago, 5734 South Ellis Avenue, Chicago, IL 60637, United States; Institut für Geologie, Universität Bern, Bern, 3012, Switzerland

Recommended Citation:
Ptáček M.P.,Dauphas N.,Greber N.D.. Chemical evolution of the continental crust from a data-driven inversion of terrigenous sediment compositions[J]. Earth and Planetary Science Letters,2020-01-01,539
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[Ptáček M.P.]'s Articles
[Dauphas N.]'s Articles
[Greber N.D.]'s Articles
百度学术
Similar articles in Baidu Scholar
[Ptáček M.P.]'s Articles
[Dauphas N.]'s Articles
[Greber N.D.]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[Ptáček M.P.]‘s Articles
[Dauphas N.]‘s Articles
[Greber N.D.]‘s Articles
Related Copyright Policies
Null
收藏/分享
所有评论 (0)
暂无评论
 

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.