High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas

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High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas. / Nicklas, Robert W.; Brandon, Alan D.; Waight, Tod E.; Puchtel, Igor S.; Day, James M.D.

I: Chemical Geology, Bind 582, 120436, 05.11.2021.

Publikation: Bidrag til tidsskriftTidsskriftartikelfagfællebedømt

Harvard

Nicklas, RW, Brandon, AD, Waight, TE, Puchtel, IS & Day, JMD 2021, 'High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas', Chemical Geology, bind 582, 120436. https://doi.org/10.1016/j.chemgeo.2021.120436

APA

Nicklas, R. W., Brandon, A. D., Waight, T. E., Puchtel, I. S., & Day, J. M. D. (2021). High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas. Chemical Geology, 582, [120436]. https://doi.org/10.1016/j.chemgeo.2021.120436

Vancouver

Nicklas RW, Brandon AD, Waight TE, Puchtel IS, Day JMD. High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas. Chemical Geology. 2021 nov. 5;582. 120436. https://doi.org/10.1016/j.chemgeo.2021.120436

Author

Nicklas, Robert W. ; Brandon, Alan D. ; Waight, Tod E. ; Puchtel, Igor S. ; Day, James M.D. / High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas. I: Chemical Geology. 2021 ; Bind 582.

Bibtex

@article{42bbcf83da7d4f8e8e855c9b8310fdd1,
title = "High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas",
abstract = "Ocean island basalts (OIB) exhibit significant variations in their 87Sr/86Sr, 143Nd/144Nd, 176Hf/177Hf, 186,187Os/188Os, and 206,207,208Pb/204Pb compositions that indicate contributions from multiple mantle sources. To further constrain the relationships between diverse long-lived isotopic systems in OIB, new double-spike Pb and Hf isotope data, as well as isotope dilution highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundances are reported for nineteen Icelandic picrites and basalts for which 3He/4He, 87Sr/86Sr, 143Nd/144Nd, and 186,187Os/188Os data have been reported previously (Brandon et al., 2007. GCA). Hafnium-Nd-He isotope systematics for the sample set reveal the presence of an ancient refractory source with low-3He/4He, while He-Pb isotope correlations indicate that recycled oceanic crustal components with high-3He/4He added from a less degassed mantle source are present in the Iceland plume. The highly depleted, low-3He/4He signature is sampled in the Northern and Western Volcanic Zones, likely due to higher degrees of partial melting at those localities enabling sampling of this refractory endmember. The 187Os/188Os ratios show correlations with Pb, Hf, and Nd isotope ratios indicating binary mixing between depleted and enriched sources, with no evidence for decoupling due to sulfide metasomatism. The spread of 187Os/188Os- 206,207,208Pb/204Pb data can be explained by addition of 1–11% young recycled oceanic crust to a depleted mantle source distinct from the source of Atlantic MORB. Abundances of the HSE in Northern and Western Volcanic Zone lavas overlap with those from other OIB with similar MgO contents, showing fractionated patterns that are enriched in the more incompatible Re, Pd, and Pt over the compatible Ru, Ir, and Os. Calculated parental melt HSE abundances of those lavas also overlap with those of other OIB. Eastern Volcanic Zone lavas are highly depleted in Pt and Pd relative to other Icelandic lavas. Abundances of Pt and Pd correlate with isotopic parameters, such as 206Pb/204Pb, in Icelandic lavas, indicating that the isotopically enriched endmember sampled in the Eastern Volcanic Zone is depleted in the HSE, consistent with it being mafic in nature. The abundances of MgO in the lavas also roughly correlate with isotopic parameters, supporting the identity of the depleted endmember as ultramafic and the enriched endmember as mafic. New and previously published double-spike Pb isotope data show chiefly binary mixing with an additional component present in the vicinity of the volcano {\"O}r{\ae}faj{\"o}kull. Icelandic 207Pb/204Pb and 208Pb/204Pb data plot below and above the majority of Mid-Atlantic Ridge basalt data, respectively, indicating that both depleted and enriched end-members in the plume have a lower U depletion age and a higher Th/U than ambient mantle. This is consistent with the enriched and depleted end-members within the Iceland plume being <2 Ga recycled oceanic crust and lithospheric mantle, respectively.",
keywords = "Hf Isotopes, Highly siderophile elements, Iceland, Mantle geochemistry, Ocean Island Basalts, Pb isotopes",
author = "Nicklas, {Robert W.} and Brandon, {Alan D.} and Waight, {Tod E.} and Puchtel, {Igor S.} and Day, {James M.D.}",
note = "Funding Information: Joel Baker is thanked for his leadership and guidance in the DLC Axiom MC-ICPMS laboratory. Fieldwork to gather the sample set was funded by NSF EAR Grant 0000908 to A.D.B and NSF EAR Grant 1918322 “A Mixed-Up Mantle Beneath Ocean Islands?” to JMDD. This manuscript was greatly improved by the constructive comments of reviewers Marcel Regelous and Andreas Stracke and the editor Balz Kamber. Publisher Copyright: {\textcopyright} 2021 Elsevier B.V.",
year = "2021",
month = nov,
day = "5",
doi = "10.1016/j.chemgeo.2021.120436",
language = "English",
volume = "582",
journal = "Chemical Geology",
issn = "0009-2541",
publisher = "Elsevier",

}

RIS

TY - JOUR

T1 - High-precision Pb and Hf isotope and highly siderophile element abundance systematics of high-MgO Icelandic lavas

AU - Nicklas, Robert W.

AU - Brandon, Alan D.

AU - Waight, Tod E.

AU - Puchtel, Igor S.

AU - Day, James M.D.

N1 - Funding Information: Joel Baker is thanked for his leadership and guidance in the DLC Axiom MC-ICPMS laboratory. Fieldwork to gather the sample set was funded by NSF EAR Grant 0000908 to A.D.B and NSF EAR Grant 1918322 “A Mixed-Up Mantle Beneath Ocean Islands?” to JMDD. This manuscript was greatly improved by the constructive comments of reviewers Marcel Regelous and Andreas Stracke and the editor Balz Kamber. Publisher Copyright: © 2021 Elsevier B.V.

PY - 2021/11/5

Y1 - 2021/11/5

N2 - Ocean island basalts (OIB) exhibit significant variations in their 87Sr/86Sr, 143Nd/144Nd, 176Hf/177Hf, 186,187Os/188Os, and 206,207,208Pb/204Pb compositions that indicate contributions from multiple mantle sources. To further constrain the relationships between diverse long-lived isotopic systems in OIB, new double-spike Pb and Hf isotope data, as well as isotope dilution highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundances are reported for nineteen Icelandic picrites and basalts for which 3He/4He, 87Sr/86Sr, 143Nd/144Nd, and 186,187Os/188Os data have been reported previously (Brandon et al., 2007. GCA). Hafnium-Nd-He isotope systematics for the sample set reveal the presence of an ancient refractory source with low-3He/4He, while He-Pb isotope correlations indicate that recycled oceanic crustal components with high-3He/4He added from a less degassed mantle source are present in the Iceland plume. The highly depleted, low-3He/4He signature is sampled in the Northern and Western Volcanic Zones, likely due to higher degrees of partial melting at those localities enabling sampling of this refractory endmember. The 187Os/188Os ratios show correlations with Pb, Hf, and Nd isotope ratios indicating binary mixing between depleted and enriched sources, with no evidence for decoupling due to sulfide metasomatism. The spread of 187Os/188Os- 206,207,208Pb/204Pb data can be explained by addition of 1–11% young recycled oceanic crust to a depleted mantle source distinct from the source of Atlantic MORB. Abundances of the HSE in Northern and Western Volcanic Zone lavas overlap with those from other OIB with similar MgO contents, showing fractionated patterns that are enriched in the more incompatible Re, Pd, and Pt over the compatible Ru, Ir, and Os. Calculated parental melt HSE abundances of those lavas also overlap with those of other OIB. Eastern Volcanic Zone lavas are highly depleted in Pt and Pd relative to other Icelandic lavas. Abundances of Pt and Pd correlate with isotopic parameters, such as 206Pb/204Pb, in Icelandic lavas, indicating that the isotopically enriched endmember sampled in the Eastern Volcanic Zone is depleted in the HSE, consistent with it being mafic in nature. The abundances of MgO in the lavas also roughly correlate with isotopic parameters, supporting the identity of the depleted endmember as ultramafic and the enriched endmember as mafic. New and previously published double-spike Pb isotope data show chiefly binary mixing with an additional component present in the vicinity of the volcano Öræfajökull. Icelandic 207Pb/204Pb and 208Pb/204Pb data plot below and above the majority of Mid-Atlantic Ridge basalt data, respectively, indicating that both depleted and enriched end-members in the plume have a lower U depletion age and a higher Th/U than ambient mantle. This is consistent with the enriched and depleted end-members within the Iceland plume being <2 Ga recycled oceanic crust and lithospheric mantle, respectively.

AB - Ocean island basalts (OIB) exhibit significant variations in their 87Sr/86Sr, 143Nd/144Nd, 176Hf/177Hf, 186,187Os/188Os, and 206,207,208Pb/204Pb compositions that indicate contributions from multiple mantle sources. To further constrain the relationships between diverse long-lived isotopic systems in OIB, new double-spike Pb and Hf isotope data, as well as isotope dilution highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, and Re) abundances are reported for nineteen Icelandic picrites and basalts for which 3He/4He, 87Sr/86Sr, 143Nd/144Nd, and 186,187Os/188Os data have been reported previously (Brandon et al., 2007. GCA). Hafnium-Nd-He isotope systematics for the sample set reveal the presence of an ancient refractory source with low-3He/4He, while He-Pb isotope correlations indicate that recycled oceanic crustal components with high-3He/4He added from a less degassed mantle source are present in the Iceland plume. The highly depleted, low-3He/4He signature is sampled in the Northern and Western Volcanic Zones, likely due to higher degrees of partial melting at those localities enabling sampling of this refractory endmember. The 187Os/188Os ratios show correlations with Pb, Hf, and Nd isotope ratios indicating binary mixing between depleted and enriched sources, with no evidence for decoupling due to sulfide metasomatism. The spread of 187Os/188Os- 206,207,208Pb/204Pb data can be explained by addition of 1–11% young recycled oceanic crust to a depleted mantle source distinct from the source of Atlantic MORB. Abundances of the HSE in Northern and Western Volcanic Zone lavas overlap with those from other OIB with similar MgO contents, showing fractionated patterns that are enriched in the more incompatible Re, Pd, and Pt over the compatible Ru, Ir, and Os. Calculated parental melt HSE abundances of those lavas also overlap with those of other OIB. Eastern Volcanic Zone lavas are highly depleted in Pt and Pd relative to other Icelandic lavas. Abundances of Pt and Pd correlate with isotopic parameters, such as 206Pb/204Pb, in Icelandic lavas, indicating that the isotopically enriched endmember sampled in the Eastern Volcanic Zone is depleted in the HSE, consistent with it being mafic in nature. The abundances of MgO in the lavas also roughly correlate with isotopic parameters, supporting the identity of the depleted endmember as ultramafic and the enriched endmember as mafic. New and previously published double-spike Pb isotope data show chiefly binary mixing with an additional component present in the vicinity of the volcano Öræfajökull. Icelandic 207Pb/204Pb and 208Pb/204Pb data plot below and above the majority of Mid-Atlantic Ridge basalt data, respectively, indicating that both depleted and enriched end-members in the plume have a lower U depletion age and a higher Th/U than ambient mantle. This is consistent with the enriched and depleted end-members within the Iceland plume being <2 Ga recycled oceanic crust and lithospheric mantle, respectively.

KW - Hf Isotopes

KW - Highly siderophile elements

KW - Iceland

KW - Mantle geochemistry

KW - Ocean Island Basalts

KW - Pb isotopes

U2 - 10.1016/j.chemgeo.2021.120436

DO - 10.1016/j.chemgeo.2021.120436

M3 - Journal article

AN - SCOPUS:85110459452

VL - 582

JO - Chemical Geology

JF - Chemical Geology

SN - 0009-2541

M1 - 120436

ER -

ID: 281989297