Vanadium Isotopic Compositions of the High‐ ³He/⁴He Baffin Island Lavas
Abstract
The isotopic composition of vanadium (V) in hotspot lavas provides new insight into the source of deep mantle heterogeneities. We measured V isotopic compositions in Paleogene Baffin Island lavas, which erupted above the Iceland plume head, to constrain the mantle plume source. These lavas have V isotopic compositions that are lighter (-0.96 ± 0.02‰, 2 s.e., n = 25) than most other mantle-derived lavas (δ 51 V = -0.89 ± 0.02, 2 s.e., n = 69). This difference is statistically significant with a 99.8% confidence interval. The measured 51 V/ 50 V ratio in Baffin Island is difficult to reconcile with the assimilation of continental crust, fractional crystallization, crystal accumulation, isotopic fractionation during mantle melting, or the recycling of sediments. Possibly, the Baffin Island lavas sample an ancient (>3 Ga) melt-depleted mantle reservoir. However, this cannot explain the similarly low 51 V/ 50 V measured in younger lavas related to the Iceland plume. Instead, the V isotopic composition of Baffin Island lavas may be consistent with the incorporation of core-affected material into the Iceland plume. The advection of bulk core into the lowermost mantle is improbable, so we hypothesize that, if the V isotopic difference is due to core-mantle interactions, V partitioned into core-exsolved oxides that imparted a core-like V isotopic composition on the Baffin Island mantle source.
Related
- A simplified, non-automated, DGA-based resin protocol for the separation of Ca, Sr and REE: Validation for Ca, stable and radiogenic Sr isotopic compositions
- Diet and isotopic ecology of subantarctic fur seal at the subtropical Amsterdam Island
- Xenon isotopes in the Fani Maoré lavas: Implications for upper mantle heterogeneity
- Pelagic and Sympagic Biogenic Silica Production During Arctic Spring Diatom Bloom in Baffin Bay: Drivers, Limitation, and Fate
- Cadmium isotope compositions of basalts from the East Pacific Rise and Southwest Indian Ridge: Implications for magma differentiation and mantle heterogeneity
BibTeX
@article{kaarerasmussen2026vanadium,
title = {{Vanadium Isotopic Compositions of the High‐ ³He/⁴He Baffin Island Lavas}},
author = {Jonas Kaare‐rasmussen and Forrest Horton and Maureen Auro and Andy W Heard and Sune G Nielsen},
journal = {Geochemistry, Geophysics, Geosystems},
year = {2026},
month = sep,
doi = {10.1029/2025gc012861},
url = {https://hal.science/hal-05763095v1},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Vanadium Isotopic Compositions of the High‐ ³He/⁴He Baffin Island Lavas
AU - Jonas Kaare‐rasmussen
AU - Forrest Horton
AU - Maureen Auro
AU - Andy W Heard
AU - Sune G Nielsen
PY - 2026
DA - 2026/09/24
JO - Geochemistry, Geophysics, Geosystems
DO - 10.1029/2025gc012861
UR - https://hal.science/hal-05763095v1
AB - The isotopic composition of vanadium (V) in hotspot lavas provides new insight into the source of deep mantle heterogeneities. We measured V isotopic compositions in Paleogene Baffin Island lavas, which erupted above the Iceland plume head, to constrain the mantle plume source. These lavas have V isotopic compositions that are lighter (-0.96 ± 0.02‰, 2 s.e., n = 25) than most other mantle-derived lavas (δ 51 V = -0.89 ± 0.02, 2 s.e., n = 69). This difference is statistically significant with a 99.8% confidence interval. The measured 51 V/ 50 V ratio in Baffin Island is difficult to reconcile with the assimilation of continental crust, fractional crystallization, crystal accumulation, isotopic fractionation during mantle melting, or the recycling of sediments. Possibly, the Baffin Island lavas sample an ancient (>3 Ga) melt-depleted mantle reservoir. However, this cannot explain the similarly low 51 V/ 50 V measured in younger lavas related to the Iceland plume. Instead, the V isotopic composition of Baffin Island lavas may be consistent with the incorporation of core-affected material into the Iceland plume. The advection of bulk core into the lowermost mantle is improbable, so we hypothesize that, if the V isotopic difference is due to core-mantle interactions, V partitioned into core-exsolved oxides that imparted a core-like V isotopic composition on the Baffin Island mantle source.
SN - 1525-2027
ER -