Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry

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Standard

Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry. / Connelly, J. N.

In: Geochemistry, Geophysics, Geosystems, Vol. 7, No. 4, Q04005, 2006.

Research output: Contribution to journal › Journal article › Research › peer-review

Harvard

Connelly, JN 2006, 'Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry', Geochemistry, Geophysics, Geosystems, vol. 7, no. 4, Q04005. https://doi.org/10.1029/2005GC001082

APA

Connelly, J. N. (2006). Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry. Geochemistry, Geophysics, Geosystems, 7(4), [Q04005]. https://doi.org/10.1029/2005GC001082

Vancouver

Connelly JN. Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry. Geochemistry, Geophysics, Geosystems. 2006;7(4). Q04005. https://doi.org/10.1029/2005GC001082

Author

Connelly, J. N. / Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry. In: Geochemistry, Geophysics, Geosystems. 2006 ; Vol. 7, No. 4.

Bibtex

@article{f31ccb4c40af4a40bff04b8484dd8384,
title = "Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry",
abstract = "Garnet-based Lu-Hf geochronology using conventional (HF-HNO3) dissolution methods may be compromised by full or partial digestion of Hf-rich zircon inclusions. This study integrates two complimentary methods to substantially reduce zircon digestion while assuring complete digestion of garnet and sample-spike equilibration. Handpicked garnet fractions are heat treated to >1000°Cinan evacuated silica glass ampoule to anneal zircon inclusions and then dissolved with 12 M HCl at 210°C and cold 28 M HF. Analyses of heat-treated garnet (and their high-temperature breakdown products orthopyroxene-spinel-quartz) from Gore Mountain, New York, demonstrate the method is capable of complete dissolution of garnet and routinely achieving sample-spike equilibration. Independent analyses of annealed and unannealed zircons dissolved by HCl- cold HF demonstrate the benefit of heat treatment prior to dissolution. Analyses of zircon-rich garnets from peletic paragneisses of Labrador, Canada, show the potential of this method by returning Lu-Hf ratios commensurate with the degree of heat treatment. Finally, a complementary chemical separation method for Lu and Hf is presented that supports analysis of garnet by MC-ICP-MS.",
keywords = "Bboric acid, Garnet, Geochronology, HCl dissolution, Hf isotopes, Lu-Hf",
author = "Connelly, {J. N.}",
year = "2006",
doi = "10.1029/2005GC001082",
language = "English",
volume = "7",
journal = "Geochemistry, Geophysics, Geosystems",
issn = "1525-2027",
publisher = "AGU Publications",
number = "4",

}

RIS

TY - JOUR

T1 - Improved dissolution and chemical separation methods for Lu-Hf garnet chronometry

AU - Connelly, J. N.

PY - 2006

Y1 - 2006

N2 - Garnet-based Lu-Hf geochronology using conventional (HF-HNO3) dissolution methods may be compromised by full or partial digestion of Hf-rich zircon inclusions. This study integrates two complimentary methods to substantially reduce zircon digestion while assuring complete digestion of garnet and sample-spike equilibration. Handpicked garnet fractions are heat treated to >1000°Cinan evacuated silica glass ampoule to anneal zircon inclusions and then dissolved with 12 M HCl at 210°C and cold 28 M HF. Analyses of heat-treated garnet (and their high-temperature breakdown products orthopyroxene-spinel-quartz) from Gore Mountain, New York, demonstrate the method is capable of complete dissolution of garnet and routinely achieving sample-spike equilibration. Independent analyses of annealed and unannealed zircons dissolved by HCl- cold HF demonstrate the benefit of heat treatment prior to dissolution. Analyses of zircon-rich garnets from peletic paragneisses of Labrador, Canada, show the potential of this method by returning Lu-Hf ratios commensurate with the degree of heat treatment. Finally, a complementary chemical separation method for Lu and Hf is presented that supports analysis of garnet by MC-ICP-MS.

AB - Garnet-based Lu-Hf geochronology using conventional (HF-HNO3) dissolution methods may be compromised by full or partial digestion of Hf-rich zircon inclusions. This study integrates two complimentary methods to substantially reduce zircon digestion while assuring complete digestion of garnet and sample-spike equilibration. Handpicked garnet fractions are heat treated to >1000°Cinan evacuated silica glass ampoule to anneal zircon inclusions and then dissolved with 12 M HCl at 210°C and cold 28 M HF. Analyses of heat-treated garnet (and their high-temperature breakdown products orthopyroxene-spinel-quartz) from Gore Mountain, New York, demonstrate the method is capable of complete dissolution of garnet and routinely achieving sample-spike equilibration. Independent analyses of annealed and unannealed zircons dissolved by HCl- cold HF demonstrate the benefit of heat treatment prior to dissolution. Analyses of zircon-rich garnets from peletic paragneisses of Labrador, Canada, show the potential of this method by returning Lu-Hf ratios commensurate with the degree of heat treatment. Finally, a complementary chemical separation method for Lu and Hf is presented that supports analysis of garnet by MC-ICP-MS.

KW - Bboric acid

KW - Garnet

KW - Geochronology

KW - HCl dissolution

KW - Hf isotopes

KW - Lu-Hf

U2 - 10.1029/2005GC001082

DO - 10.1029/2005GC001082

M3 - Journal article

AN - SCOPUS:34250305276

VL - 7

JO - Geochemistry, Geophysics, Geosystems

JF - Geochemistry, Geophysics, Geosystems

SN - 1525-2027

IS - 4

M1 - Q04005

ER -

ID: 333881792