Melting and differentiation of early-formed asteroids: The perspective from high precision oxygen isotope studies

Greenwood, Richard C.; Burbine, T. H.; Miller, Martin F.; Franchi, I. A.

doi:10.1016/j.chemer.2016.09.005

Cited by 147 publications

(242 citation statements)

References 290 publications

Supporting

Mentioning

229

Contrasting

Order By: Relevance

“…); E‐B: Emmaville bulk (Greenwood et al. , ); E‐1, E‐2, E‐3: Emmaville fractions in this study (see text for further details). Analyses of PCA 91007, Pasamonte, and A‐881394, NWA 1240 (Scott et al.…”

Section: Resultsmentioning

confidence: 99%

“…that Emmaville is an isotopically anomalous eucrite on the basis that its Δ 17 O composition lies at least 3σ outside the mean HED value for fall samples ( n = 26) Δ 17 O = −0.240 ± 0.021‰ (3σ) (Greenwood et al. ). This is in agreement with the definition of Scott et al.…”

Section: Resultsmentioning

confidence: 99%

“…() and Greenwood et al. (). It was found that ~1% H or L chondrite material was required to elevate Ni to comparable levels but did not elevate Δ 17 O significantly.…”

Section: Discussionmentioning

confidence: 99%

“…) have Δ 17 O that lie at least 3σ outside the mean value defined by the HED falls, that is, −0.240 ± 0.021‰ (3σ) ( n = 26) (Greenwood et al. ). With the exception of NWA 1240 (Scott et al.…”

Section: Discussionmentioning

confidence: 99%

“…The Emmaville eucrite is a fall and has a Δ 17 O value of −0.137 ± 0.024 ‰ (1σ) (Greenwood et al. ), substantially different from the eucrite mean of −0.246 ± 0.014 ‰ (2σ) (Greenwood et al. ), but similar to those of Asuka 881394 (A‐881394; Scott et al.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

The mineralogy, petrology, and composition of anomalous eucrite Emmaville

Barrett

Mittlefehldt

Greenwood

et al. 2017

Meteorit & Planetary Scien

View full text Add to dashboard Cite

Abstract-The Emmaville eucrite is a relatively poorly studied basaltic achondrite with an anomalous oxygen isotope signature. In this study, we report comprehensive mineralogical, petrographic, and geochemical data from Emmaville in order to understand its petrogenesis and relationship with the basaltic eucrites. Emmaville is an unusually fine-grained, hornfelsic-textured metabasalt with pervasive impact melt veins and mineral compositions similar to those of typical basaltic eucrites. The major and trace element bulk composition of Emmaville is also typical of a basaltic eucrite. Three separated individual lithologies were also analyzed for O isotopes; a dark gray fraction (E1), a shocked lithology (E2), and a lighter gray portion (E3). Fractions E1 and E2 shared similar O isotope compositions to the bulk sample (E-B), whereas the lighter gray portion (E3) is slightly elevated in D 17 O and significantly elevated in d18 O compared to bulk. No evidence for any exogenous material is observed in the thin sections, coupled with the striking compositional similarity to typical basaltic eucrites, appears to preclude a simple impact-mixing hypothesis. The O-isotopes of Emmaville are similar to those of Bunburra Rockhole, A-881394, and EET 92023, and thus distinct from the majority of the HEDs, despite having similarities in petrology, mineral, and bulk compositions. It would, therefore, seem plausible that all four of these samples are derived from a single HED-like parent body that is isotopically distinct from that of the HEDs (Vesta) but similar in composition.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

“…() and Greenwood et al. (). It was found that ~1% H or L chondrite material was required to elevate Ni to comparable levels but did not elevate Δ 17 O significantly.…”

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The mineralogy, petrology, and composition of anomalous eucrite Emmaville

Barrett

Mittlefehldt

Greenwood

et al. 2017

Meteorit & Planetary Scien

View full text Add to dashboard Cite

show abstract

Geochemistry and petrography of martian meteorite Northwest Africa 11115: A rare earth element-enriched olivine-phyric shergottite closely linked to Northwest Africa 1068

Daswani

Greber

et al. 2021

Preprint

View full text Add to dashboard Cite

Accretion of the Earth—Missing Components?

2020

View full text Add to dashboard Cite

Primitive meteorites preserve the chemical and isotopic composition of the first aggregates that formed from dust and gas in the solar nebula during the earliest stages of solar system evolution. Gradual increase in the size of solid bodies from dust to aggregates and then to planetesimals finally led to the formation of planets within a few to tens of million years after the start of condensation. Thus the rocky planets of the inner solar system are likely the result of the accumulation of numerous smaller primitive as well as differentiated bodies. The chemically most primitive known meteorites are chondrites and they consist mostly of metal and silicates. Chondritic meteorites are derived from distinct primitive planetary bodies that experienced only limited element fractionation during formation and subsequent differentiation. Different chondrite classes show distinct chemical and isotopic characteristics, which may reflect heterogeneities in the solar nebula and the slightly different pathways of their formation. To a first approximation the chemical composition of the bulk Earth bears great similarities to primitive meteorites. However, for some elements there are striking and significant differences. The Earth shows a much stronger depletion of the moderate to highly volatile elements compared to chondrites. In addition, mixing trends of specific isotopes reveal that the Earth is most enriched in s-process isotopes compared to all other analysed bulk solar system materials. It is currently not possible to fully define and quantify the different chemical and isotopic materials that formed the Earth, because a major component seems missing in the extant collections of extraterrestrial samples. Variations in nucleosynthetic isotope compositions as well as the strong depletion of moderately and strongly volatile elements points towards a source in the inner solar system for this missing material. It is conceivable that Venus and Mercury contain a much larger fraction of this

show abstract

Melting and differentiation of early-formed asteroids: The perspective from high precision oxygen isotope studies

Cited by 147 publications

References 290 publications

The mineralogy, petrology, and composition of anomalous eucrite Emmaville

The mineralogy, petrology, and composition of anomalous eucrite Emmaville

Geochemistry and petrography of martian meteorite Northwest Africa 11115: A rare earth element-enriched olivine-phyric shergottite closely linked to Northwest Africa 1068

Accretion of the Earth—Missing Components?

Contact Info

Product

Resources

About