DOI: 10.1016/j.epsl.2018.08.013
Scopus记录号: 2-s2.0-85051726432
论文题名: A complex history of silicate differentiation of Mars from Nd and Hf isotopes in crustal breccia NWA 7034
作者: Armytage R.M.G. ; Debaille V. ; Brandon A.D. ; Agee C.B.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2018
卷: 502 起始页码: 274
结束页码: 283
语种: 英语
英文关键词: Hf isotopes
; Mars
; Nd isotopes
; shergottites
; silicate differentiation
Scopus关键词: Isotopes
; Meteorites
; Orbits
; Rare earths
; Rocks
; Silicates
; Trace elements
; Early differentiation
; Hf isotope
; Isotopic composition
; Isotopic signatures
; Mars
; Nd isotopes
; Representative sample
; shergottites
; Hafnium
英文摘要: Resolving the possible mantle and crustal sources for shergottite meteorites is crucial for understanding the formation and early differentiation of Mars. Orbiter and rover characterization of the martian surface reveal that the major element composition of most of its surface does not match the shergottites (McSween et al., 2009) leaving the relationship between them poorly understood. The identification of the meteorite NWA 7034 and its pairs as a Mars surface rock (Cartwright et al., 2014) provides access to a representative sample of Mars' crust (Agee et al., 2013; Humayun et al., 2013). Utilizing the short-lived 146Sm–142Nd, and long-lived 147Sm–143Nd and 176Lu–176Hf chronometers, which are sensitive to silicate differentiation, we analyzed three fragments of NWA 7034. The very negative mean isotopic compositions for this breccia, μ142NdJNdi-1=−45±5 (2SD), ε143NdCHUR=−16.7±0.4 (2SD) and ε176HfCHUR=−61±9 (2SD) point to an ancient origin for this martian crust. However, modeling of the data shows that the crust sampled by NWA 7034 possesses a Hf/Nd ratio and coupled ε143Nd–μ142Nd model age that are incompatible with this crustal reservoir being an end-member that generated the shergottite source mixing array. In addition, this crust is not juvenile, despite its rare earth element profile, but has had a multistage formation history. Therefore, early crustal extraction alone was not responsible for the creation of the reservoirs that produced the shergottites. Instead mantle reservoirs formed via other early differentiation processes such as in a Mars magma ocean must be responsible for the trace element and isotopic signatures present in shergottites. © 2018 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109656
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: Laboratoire G-Time, CP 160/02, Université Libre de Bruxelles, Av. F. Roosevelt 50, Bruxelles, 1050, Belgium; Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, United States; Institute of Meteoritics, University of New Mexico, Albuquerque, NM 87131, United States
Recommended Citation:
Armytage R.M.G.,Debaille V.,Brandon A.D.,et al. A complex history of silicate differentiation of Mars from Nd and Hf isotopes in crustal breccia NWA 7034[J]. Earth and Planetary Science Letters,2018-01-01,502