A legacy of Hadean silicate differentiation inferred from Hf isotopes in Eoarchean rocks of the Nuvvuagittuq supracrustal belt (Québec, Canada)

Martin Guitreau, Janne Blichert-Toft, Stephen J. Mojzsis, Antoine S G Roth, Bernard Bourdon

Research output: Contribution to journalArticle

24 Citations (Scopus)

Abstract

New Lu-Hf isotopic data for mafic and felsic rocks from the Nuvvuagittuq supracrustal belt (NSB) in northern Québec (Canada) yield an Eoarchean age of 3864±70Ma consistent with both zircon U-Pb and whole-rock 147Sm-143Nd chronology, but in disagreement with ca. 4400Ma ages inferred from the 146Sm-142Nd chronometer (O'Neil et al., 2008, 2012). The Lu-Hf result is interpreted as the mean emplacement age of the different autochthonous units of the NSB. An observed alignment of the data along a Lu-Hf "scatterchron" precludes a Hadean age for the NSB because its isotopic characteristics appear to be controlled by long-term radiogenic ingrowth. Emplacement of the NSB in the Hadean (e.g., 4362-54+35 Ma if the decay constant of 146Sm of Kinoshita et al. (2012) is used with the O'Neil et al., 2008 data) should instead have caused age differences of hundreds of millions of years to manifest as strong deviations from the Lu-Hf scatterchron. Combined Lu-Hf and Sm-Nd data on the same NSB amphibolite samples (Ca-poor cummingtonite- and hornblende-bearing) define a mixing hyperbola at ca. 3800Ma with end-member compositions representative of the compositional groups identified for these lithologies (O'Neil et al., 2011). Anomalously low 142Nd/144Nd values relative to Bulk Silicate Earth are endemic to a group of rocks in the NSB termed "low-TiO2" amphibolites; this is attributable to an ancient multi-stage history of their mantle source. Modeling shows that the 142Nd/144Nd deficits could have developed in response to a re-fertilization episode within a previously fractionated mantle domain at 4510Ma.

Original languageEnglish
Pages (from-to)171-181
Number of pages11
JournalEarth and Planetary Science Letters
Volume362
DOIs
Publication statusPublished - Jan 5 2013

Fingerprint

Hadean
Silicates
Canada
Isotopes
silicates
silicate
isotopes
Rocks
isotope
rocks
rock
Chronometers
emplacement
Earth mantle
Bearings (structural)
chronometers
cummingtonite
fertilization
Lithology
chronology

Keywords

  • Amphibolite
  • Archean
  • Hadean
  • Isua
  • Lu-Hf
  • Nuvvuagittuq
  • Sm-Nd

ASJC Scopus subject areas

  • Geochemistry and Petrology
  • Geophysics
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science

Cite this

A legacy of Hadean silicate differentiation inferred from Hf isotopes in Eoarchean rocks of the Nuvvuagittuq supracrustal belt (Québec, Canada). / Guitreau, Martin; Blichert-Toft, Janne; Mojzsis, Stephen J.; Roth, Antoine S G; Bourdon, Bernard.

In: Earth and Planetary Science Letters, Vol. 362, 05.01.2013, p. 171-181.

Research output: Contribution to journalArticle

@article{2013452455454502bc4f1f3bbd87c9d1,
title = "A legacy of Hadean silicate differentiation inferred from Hf isotopes in Eoarchean rocks of the Nuvvuagittuq supracrustal belt (Qu{\'e}bec, Canada)",
abstract = "New Lu-Hf isotopic data for mafic and felsic rocks from the Nuvvuagittuq supracrustal belt (NSB) in northern Qu{\'e}bec (Canada) yield an Eoarchean age of 3864±70Ma consistent with both zircon U-Pb and whole-rock 147Sm-143Nd chronology, but in disagreement with ca. 4400Ma ages inferred from the 146Sm-142Nd chronometer (O'Neil et al., 2008, 2012). The Lu-Hf result is interpreted as the mean emplacement age of the different autochthonous units of the NSB. An observed alignment of the data along a Lu-Hf {"}scatterchron{"} precludes a Hadean age for the NSB because its isotopic characteristics appear to be controlled by long-term radiogenic ingrowth. Emplacement of the NSB in the Hadean (e.g., 4362-54+35 Ma if the decay constant of 146Sm of Kinoshita et al. (2012) is used with the O'Neil et al., 2008 data) should instead have caused age differences of hundreds of millions of years to manifest as strong deviations from the Lu-Hf scatterchron. Combined Lu-Hf and Sm-Nd data on the same NSB amphibolite samples (Ca-poor cummingtonite- and hornblende-bearing) define a mixing hyperbola at ca. 3800Ma with end-member compositions representative of the compositional groups identified for these lithologies (O'Neil et al., 2011). Anomalously low 142Nd/144Nd values relative to Bulk Silicate Earth are endemic to a group of rocks in the NSB termed {"}low-TiO2{"} amphibolites; this is attributable to an ancient multi-stage history of their mantle source. Modeling shows that the 142Nd/144Nd deficits could have developed in response to a re-fertilization episode within a previously fractionated mantle domain at 4510Ma.",
keywords = "Amphibolite, Archean, Hadean, Isua, Lu-Hf, Nuvvuagittuq, Sm-Nd",
author = "Martin Guitreau and Janne Blichert-Toft and Mojzsis, {Stephen J.} and Roth, {Antoine S G} and Bernard Bourdon",
year = "2013",
month = "1",
day = "5",
doi = "10.1016/j.epsl.2012.11.055",
language = "English",
volume = "362",
pages = "171--181",
journal = "Earth and Planetary Sciences Letters",
issn = "0012-821X",
publisher = "Elsevier",

}

TY - JOUR

T1 - A legacy of Hadean silicate differentiation inferred from Hf isotopes in Eoarchean rocks of the Nuvvuagittuq supracrustal belt (Québec, Canada)

AU - Guitreau, Martin

AU - Blichert-Toft, Janne

AU - Mojzsis, Stephen J.

AU - Roth, Antoine S G

AU - Bourdon, Bernard

PY - 2013/1/5

Y1 - 2013/1/5

N2 - New Lu-Hf isotopic data for mafic and felsic rocks from the Nuvvuagittuq supracrustal belt (NSB) in northern Québec (Canada) yield an Eoarchean age of 3864±70Ma consistent with both zircon U-Pb and whole-rock 147Sm-143Nd chronology, but in disagreement with ca. 4400Ma ages inferred from the 146Sm-142Nd chronometer (O'Neil et al., 2008, 2012). The Lu-Hf result is interpreted as the mean emplacement age of the different autochthonous units of the NSB. An observed alignment of the data along a Lu-Hf "scatterchron" precludes a Hadean age for the NSB because its isotopic characteristics appear to be controlled by long-term radiogenic ingrowth. Emplacement of the NSB in the Hadean (e.g., 4362-54+35 Ma if the decay constant of 146Sm of Kinoshita et al. (2012) is used with the O'Neil et al., 2008 data) should instead have caused age differences of hundreds of millions of years to manifest as strong deviations from the Lu-Hf scatterchron. Combined Lu-Hf and Sm-Nd data on the same NSB amphibolite samples (Ca-poor cummingtonite- and hornblende-bearing) define a mixing hyperbola at ca. 3800Ma with end-member compositions representative of the compositional groups identified for these lithologies (O'Neil et al., 2011). Anomalously low 142Nd/144Nd values relative to Bulk Silicate Earth are endemic to a group of rocks in the NSB termed "low-TiO2" amphibolites; this is attributable to an ancient multi-stage history of their mantle source. Modeling shows that the 142Nd/144Nd deficits could have developed in response to a re-fertilization episode within a previously fractionated mantle domain at 4510Ma.

AB - New Lu-Hf isotopic data for mafic and felsic rocks from the Nuvvuagittuq supracrustal belt (NSB) in northern Québec (Canada) yield an Eoarchean age of 3864±70Ma consistent with both zircon U-Pb and whole-rock 147Sm-143Nd chronology, but in disagreement with ca. 4400Ma ages inferred from the 146Sm-142Nd chronometer (O'Neil et al., 2008, 2012). The Lu-Hf result is interpreted as the mean emplacement age of the different autochthonous units of the NSB. An observed alignment of the data along a Lu-Hf "scatterchron" precludes a Hadean age for the NSB because its isotopic characteristics appear to be controlled by long-term radiogenic ingrowth. Emplacement of the NSB in the Hadean (e.g., 4362-54+35 Ma if the decay constant of 146Sm of Kinoshita et al. (2012) is used with the O'Neil et al., 2008 data) should instead have caused age differences of hundreds of millions of years to manifest as strong deviations from the Lu-Hf scatterchron. Combined Lu-Hf and Sm-Nd data on the same NSB amphibolite samples (Ca-poor cummingtonite- and hornblende-bearing) define a mixing hyperbola at ca. 3800Ma with end-member compositions representative of the compositional groups identified for these lithologies (O'Neil et al., 2011). Anomalously low 142Nd/144Nd values relative to Bulk Silicate Earth are endemic to a group of rocks in the NSB termed "low-TiO2" amphibolites; this is attributable to an ancient multi-stage history of their mantle source. Modeling shows that the 142Nd/144Nd deficits could have developed in response to a re-fertilization episode within a previously fractionated mantle domain at 4510Ma.

KW - Amphibolite

KW - Archean

KW - Hadean

KW - Isua

KW - Lu-Hf

KW - Nuvvuagittuq

KW - Sm-Nd

UR - http://www.scopus.com/inward/record.url?scp=84872255306&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84872255306&partnerID=8YFLogxK

U2 - 10.1016/j.epsl.2012.11.055

DO - 10.1016/j.epsl.2012.11.055

M3 - Article

VL - 362

SP - 171

EP - 181

JO - Earth and Planetary Sciences Letters

JF - Earth and Planetary Sciences Letters

SN - 0012-821X

ER -