DOI: 10.1073/pnas.2009431117
论文题名: Constraining crustal silica on ancient Earth
作者: Keller C.B. ; Harrison T.M.
刊名: Proceedings of the National Academy of Sciences of the United States of America
ISSN: 0027-8424
出版年: 2020
卷: 117, 期: 35 起始页码: 21101
结束页码: 21107
语种: 英语
英文关键词: Archean
; Continental crust
; Hadean
; Plate tectonics
Scopus关键词: cerium
; chromium
; cobalt
; copper
; magnesium oxide
; neodymium
; nickel
; rubidium
; samarium
; silicon dioxide
; silver
; strontium
; trace element
; zinc
; Archean
; Article
; astronomy
; chemical composition
; climate
; oxidation
; parsimony analysis
; priority journal
; quantitative analysis
; rock
英文摘要: Accurately quantifying the composition of continental crust on Hadean and Archean Earth is critical to our understanding of the physiography, tectonics, and climate of our planet at the dawn of life. One longstanding paradigm involves the growth of a relatively mafic planetary crust over the first 1 to 2 billion years of Earth history, implying a lack of modern plate tectonics and a paucity of subaerial crust, and consequently lacking an efficient mechanism to regulate climate. Others have proposed a more uniformitarian view in which Archean and Hadean continents were only slightly more mafic than at present. Apart from complications in assessing early crustal composition introduced by crustal preservation and sampling biases, effects such as the secular cooling of Earth's mantle and the biologically driven oxidation of Earth's atmosphere have not been fully investigated.We find that the former complicates efforts to infer crustal silica from compatible or incompatible element abundances, while the latter undermines estimates of crustal silica content inferred from terrigenous sediments. Accounting for these complications, we find that the data are most parsimoniously explained by a model with nearly constant crustal silica since at least the early Archean. © 2020 National Academy of Sciences. All rights reserved. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/164067
Appears in Collections: 气候变化与战略
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作者单位: Keller, C.B., Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, United States; Harrison, T.M., Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095, United States
Recommended Citation:
Keller C.B.,Harrison T.M.. Constraining crustal silica on ancient Earth[J]. Proceedings of the National Academy of Sciences of the United States of America,2020-01-01,117(35)