Evolution of the sources of TTG and associated rocks during the Archean from in-situ 87Sr/86Sr isotope analysis of apatite by LA-MC-ICPMS

Summer A. Caton; Matthijs A. Smit; Robert B. Emo; Kira A. Musiyachenko; Melanie Kielman-Schmitt; Ellen Kooijman; Anders Scherstén; Jaana Halla; Wouter Bleeker; J. Elis Hoffmann; Om Prakash Pandey; Arathy Ravindran; Alessandro Maltese; Klaus Mezger

doi:10.1016/j.lithos.2022.106830

Evolution of the sources of TTG and associated rocks during the Archean from in-situ ⁸⁷Sr/⁸⁶Sr isotope analysis of apatite by LA-MC-ICPMS

Summer A. Caton, Matthijs A. Smit, Robert B. Emo, Kira A. Musiyachenko, Melanie Kielman-Schmitt, Ellen Kooijman, Anders Scherstén, Jaana Halla, Wouter Bleeker, J. Elis Hoffmann, Om Prakash Pandey, Arathy Ravindran, Alessandro Maltese, Klaus Mezger

Lithosphere and Biosphere Science

Research output: Contribution to journal › Article › peer-review

Abstract

Radiogenic isotopes provide an important means towards elucidating Archean crustal evolution. The global Hf and Nd isotope record of Archean crustal fragments has been instrumental to unveiling the history of ancient crustal growth and differentiation. The Rb-Sr system could provide valuable complementary constraints in this regard, as this system is particularly sensitive to magmatic fractionation processes, and the chemical and isotopic evolution of magma sources. Application of this system has so far been complicated, however, by its susceptibility to isotope re-equilibration or alteration of the Rb/Sr parent-daughter ratio. In-situ Sr isotope analysis of primary igneous minerals with very low Rb/Sr, such as apatite, provides a new means to determine the initial ⁸⁷Sr/⁸⁶Sr (⁸⁷Sr/⁸⁶Sr_i) values for igneous rocks directly. In this study, we apply in-situ Sr isotope analysis of apatite by LA-MC-ICPMS to tonalite-trondhjemite-granodiorite (TTG) rocks and end-member sanukitoids from Archean cratons worldwide. The ⁸⁷Sr/⁸⁶Sr_i values of sanukitoids are relatively radiogenic, supporting the model in which such rocks are formed by flux melting of a mantle strongly enriched by metasomatism, possibly by slab-derived fluids. The ⁸⁷Sr/⁸⁶Sr_i values for TTGs formed between 3.72 and 3.45 Ga are generally radiogenic, indicating aged amphibolite sources. The ⁸⁷Sr/⁸⁶Sr_i values of younger TTGs are systematically lower and were derived from mafic sources that had an average age of ≤0.2 Gyr. This evolution matches with observations from Hf isotopes for TTGs of similar age and indicates a systematic change in the nature or efficiency of TTG crust formation during the Paleoarchean. In-situ Sr isotope analysis of apatite provides a useful method to uncover the Sr record of the early continental crust, and enables constraints on local source evolution and the general two-step evolutionary process of Archean crust formation.

Original language	English
Article number	106830
Journal	Lithos
Volume	428-429
DOIs	https://doi.org/10.1016/j.lithos.2022.106830
Publication status	Published - 2022 Nov 1

Subject classification (UKÄ)

Geochemistry

Free keywords

Apatite
Archean
LA-MC-ICPMS
Rb-Sr
Sanukitoid
TTG

Access to Document

10.1016/j.lithos.2022.106830

Cite this

Caton, S. A., Smit, M. A., Emo, R. B., Musiyachenko, K. A., Kielman-Schmitt, M., Kooijman, E., Scherstén, A., Halla, J., Bleeker, W., Hoffmann, J. E., Pandey, O. P., Ravindran, A., Maltese, A., & Mezger, K. (2022). Evolution of the sources of TTG and associated rocks during the Archean from in-situ ⁸⁷Sr/⁸⁶Sr isotope analysis of apatite by LA-MC-ICPMS. Lithos, 428-429, Article 106830. https://doi.org/10.1016/j.lithos.2022.106830

@article{7dbacf947a2b48768fdab1c1782bcaab,

title = "Evolution of the sources of TTG and associated rocks during the Archean from in-situ 87Sr/86Sr isotope analysis of apatite by LA-MC-ICPMS",

abstract = "Radiogenic isotopes provide an important means towards elucidating Archean crustal evolution. The global Hf and Nd isotope record of Archean crustal fragments has been instrumental to unveiling the history of ancient crustal growth and differentiation. The Rb-Sr system could provide valuable complementary constraints in this regard, as this system is particularly sensitive to magmatic fractionation processes, and the chemical and isotopic evolution of magma sources. Application of this system has so far been complicated, however, by its susceptibility to isotope re-equilibration or alteration of the Rb/Sr parent-daughter ratio. In-situ Sr isotope analysis of primary igneous minerals with very low Rb/Sr, such as apatite, provides a new means to determine the initial 87Sr/86Sr (87Sr/86Sri) values for igneous rocks directly. In this study, we apply in-situ Sr isotope analysis of apatite by LA-MC-ICPMS to tonalite-trondhjemite-granodiorite (TTG) rocks and end-member sanukitoids from Archean cratons worldwide. The 87Sr/86Sri values of sanukitoids are relatively radiogenic, supporting the model in which such rocks are formed by flux melting of a mantle strongly enriched by metasomatism, possibly by slab-derived fluids. The 87Sr/86Sri values for TTGs formed between 3.72 and 3.45 Ga are generally radiogenic, indicating aged amphibolite sources. The 87Sr/86Sri values of younger TTGs are systematically lower and were derived from mafic sources that had an average age of ≤0.2 Gyr. This evolution matches with observations from Hf isotopes for TTGs of similar age and indicates a systematic change in the nature or efficiency of TTG crust formation during the Paleoarchean. In-situ Sr isotope analysis of apatite provides a useful method to uncover the Sr record of the early continental crust, and enables constraints on local source evolution and the general two-step evolutionary process of Archean crust formation.",

keywords = "Apatite, Archean, LA-MC-ICPMS, Rb-Sr, Sanukitoid, TTG",

author = "Caton, {Summer A.} and Smit, {Matthijs A.} and Emo, {Robert B.} and Musiyachenko, {Kira A.} and Melanie Kielman-Schmitt and Ellen Kooijman and Anders Scherst{\'e}n and Jaana Halla and Wouter Bleeker and Hoffmann, {J. Elis} and Pandey, {Om Prakash} and Arathy Ravindran and Alessandro Maltese and Klaus Mezger",

year = "2022",

month = nov,

day = "1",

doi = "10.1016/j.lithos.2022.106830",

language = "English",

volume = "428-429",

journal = "Lithos",

issn = "0024-4937",

publisher = "Elsevier",

}

Caton, SA, Smit, MA, Emo, RB, Musiyachenko, KA, Kielman-Schmitt, M, Kooijman, E, Scherstén, A, Halla, J, Bleeker, W, Hoffmann, JE, Pandey, OP, Ravindran, A, Maltese, A & Mezger, K 2022, 'Evolution of the sources of TTG and associated rocks during the Archean from in-situ ⁸⁷Sr/⁸⁶Sr isotope analysis of apatite by LA-MC-ICPMS', Lithos, vol. 428-429, 106830. https://doi.org/10.1016/j.lithos.2022.106830

TY - JOUR

T1 - Evolution of the sources of TTG and associated rocks during the Archean from in-situ 87Sr/86Sr isotope analysis of apatite by LA-MC-ICPMS

AU - Caton, Summer A.

AU - Smit, Matthijs A.

AU - Emo, Robert B.

AU - Musiyachenko, Kira A.

AU - Kielman-Schmitt, Melanie

AU - Kooijman, Ellen

AU - Scherstén, Anders

AU - Halla, Jaana

AU - Bleeker, Wouter

AU - Hoffmann, J. Elis

AU - Pandey, Om Prakash

AU - Ravindran, Arathy

AU - Maltese, Alessandro

AU - Mezger, Klaus

PY - 2022/11/1

Y1 - 2022/11/1

N2 - Radiogenic isotopes provide an important means towards elucidating Archean crustal evolution. The global Hf and Nd isotope record of Archean crustal fragments has been instrumental to unveiling the history of ancient crustal growth and differentiation. The Rb-Sr system could provide valuable complementary constraints in this regard, as this system is particularly sensitive to magmatic fractionation processes, and the chemical and isotopic evolution of magma sources. Application of this system has so far been complicated, however, by its susceptibility to isotope re-equilibration or alteration of the Rb/Sr parent-daughter ratio. In-situ Sr isotope analysis of primary igneous minerals with very low Rb/Sr, such as apatite, provides a new means to determine the initial 87Sr/86Sr (87Sr/86Sri) values for igneous rocks directly. In this study, we apply in-situ Sr isotope analysis of apatite by LA-MC-ICPMS to tonalite-trondhjemite-granodiorite (TTG) rocks and end-member sanukitoids from Archean cratons worldwide. The 87Sr/86Sri values of sanukitoids are relatively radiogenic, supporting the model in which such rocks are formed by flux melting of a mantle strongly enriched by metasomatism, possibly by slab-derived fluids. The 87Sr/86Sri values for TTGs formed between 3.72 and 3.45 Ga are generally radiogenic, indicating aged amphibolite sources. The 87Sr/86Sri values of younger TTGs are systematically lower and were derived from mafic sources that had an average age of ≤0.2 Gyr. This evolution matches with observations from Hf isotopes for TTGs of similar age and indicates a systematic change in the nature or efficiency of TTG crust formation during the Paleoarchean. In-situ Sr isotope analysis of apatite provides a useful method to uncover the Sr record of the early continental crust, and enables constraints on local source evolution and the general two-step evolutionary process of Archean crust formation.

AB - Radiogenic isotopes provide an important means towards elucidating Archean crustal evolution. The global Hf and Nd isotope record of Archean crustal fragments has been instrumental to unveiling the history of ancient crustal growth and differentiation. The Rb-Sr system could provide valuable complementary constraints in this regard, as this system is particularly sensitive to magmatic fractionation processes, and the chemical and isotopic evolution of magma sources. Application of this system has so far been complicated, however, by its susceptibility to isotope re-equilibration or alteration of the Rb/Sr parent-daughter ratio. In-situ Sr isotope analysis of primary igneous minerals with very low Rb/Sr, such as apatite, provides a new means to determine the initial 87Sr/86Sr (87Sr/86Sri) values for igneous rocks directly. In this study, we apply in-situ Sr isotope analysis of apatite by LA-MC-ICPMS to tonalite-trondhjemite-granodiorite (TTG) rocks and end-member sanukitoids from Archean cratons worldwide. The 87Sr/86Sri values of sanukitoids are relatively radiogenic, supporting the model in which such rocks are formed by flux melting of a mantle strongly enriched by metasomatism, possibly by slab-derived fluids. The 87Sr/86Sri values for TTGs formed between 3.72 and 3.45 Ga are generally radiogenic, indicating aged amphibolite sources. The 87Sr/86Sri values of younger TTGs are systematically lower and were derived from mafic sources that had an average age of ≤0.2 Gyr. This evolution matches with observations from Hf isotopes for TTGs of similar age and indicates a systematic change in the nature or efficiency of TTG crust formation during the Paleoarchean. In-situ Sr isotope analysis of apatite provides a useful method to uncover the Sr record of the early continental crust, and enables constraints on local source evolution and the general two-step evolutionary process of Archean crust formation.

KW - Apatite

KW - Archean

KW - LA-MC-ICPMS

KW - Rb-Sr

KW - Sanukitoid

KW - TTG

U2 - 10.1016/j.lithos.2022.106830

DO - 10.1016/j.lithos.2022.106830

M3 - Article

AN - SCOPUS:85135686503

SN - 0024-4937

VL - 428-429

JO - Lithos

JF - Lithos

M1 - 106830

ER -