Role of sulfide saturation in the petrogenesis of nakhlites and chassignites
Abstract
The nakhlite and chassignite meteorites are the only confirmed group of rocks derived from a single volcanic system on Mars, offering a unique opportunity to investigate the composition of the martian mantle and magmatic differentiation mechanisms. Nakhlites and chassignites are thought to result from low-degree partial melting of a hydrated and metasomatized depleted mantle lithosphere, unlike shergottites that predominantly sample deeper mantle reservoirs. This study presents the first comprehensive dataset on highly siderophile element (HSE: Au, Re, Pd, Rh, Pt, Ru, Ir, Os) abundances in sulfide assemblages from twelve nakhlites and two chassignites, together with siderophile (Ni, Co, W) and chalcophile (Cu, Se, Zn, Pb) element abundance data. Sulfides in chassignites exhibit relatively high total HSE abundances at ~ 5 × carbonaceous (CI) chondrite abundances, with patterns that are generally flat, apart from notable enrichments in Pt and/or Ru. Conversely, nakhlite sulfides display more fractionated HSE patterns with total HSE abundances ~ 1.6 × CI, characterized by lower overall abundances and enrichment in Re, Pt and Pd relative to Ru, Ir and Os. These results confirm that sulfides are the principal reservoirs of the HSE in chassignites and nakhlites. Fractionation modeling suggests that the nakhlite compositions can be reproduced following up to 15 % fractional crystallization through the removal of an olivine (+Cr-spinel)-dominated cumulate, while chassignites experienced between 20 to 30 % of fractionation. The preservation of magmatic signatures in sulfide HSE compositions allows for an in-depth reconstruction of the evolution of the nakhlite-chassignite parental melt composition.
Related
- NJL-Chiral Soliton and the Nucleon Equation of State at supra-saturation density: Impact of Chiral Symmetry Restoration
- A Clearer View of HAT-P-1 b: JWST NIRSpec G395H Reveals Water, Carbon Dioxide, and Possibly Hydrogen Sulfide
- A Clearer View of HAT-P-1 b: JWST NIRSpec G395H Reveals Water, Carbon Dioxide, and Possibly Hydrogen Sulfide
- Saturation Level of the Streaming Instability
- Nancy Grace Roman Space Telescope Wide Field Instrument: Grism Saturation Response to Bright Sources during Thermal-Vacuum Testing
BibTeX
@article{paquet2026role,
title = {{Role of sulfide saturation in the petrogenesis of nakhlites and chassignites}},
author = {Marine Paquet and James M.D. Day and Arya Udry},
journal = {Geochimica et Cosmochimica Acta},
year = {2026},
month = oct,
doi = {10.1016/j.gca.2025.12.019},
url = {https://hal.science/hal-05794195v1},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Role of sulfide saturation in the petrogenesis of nakhlites and chassignites
AU - Marine Paquet
AU - James M.D. Day
AU - Arya Udry
PY - 2026
DA - 2026/10/12
JO - Geochimica et Cosmochimica Acta
DO - 10.1016/j.gca.2025.12.019
UR - https://hal.science/hal-05794195v1
AB - The nakhlite and chassignite meteorites are the only confirmed group of rocks derived from a single volcanic system on Mars, offering a unique opportunity to investigate the composition of the martian mantle and magmatic differentiation mechanisms. Nakhlites and chassignites are thought to result from low-degree partial melting of a hydrated and metasomatized depleted mantle lithosphere, unlike shergottites that predominantly sample deeper mantle reservoirs. This study presents the first comprehensive dataset on highly siderophile element (HSE: Au, Re, Pd, Rh, Pt, Ru, Ir, Os) abundances in sulfide assemblages from twelve nakhlites and two chassignites, together with siderophile (Ni, Co, W) and chalcophile (Cu, Se, Zn, Pb) element abundance data. Sulfides in chassignites exhibit relatively high total HSE abundances at ~ 5 × carbonaceous (CI) chondrite abundances, with patterns that are generally flat, apart from notable enrichments in Pt and/or Ru. Conversely, nakhlite sulfides display more fractionated HSE patterns with total HSE abundances ~ 1.6 × CI, characterized by lower overall abundances and enrichment in Re, Pt and Pd relative to Ru, Ir and Os. These results confirm that sulfides are the principal reservoirs of the HSE in chassignites and nakhlites. Fractionation modeling suggests that the nakhlite compositions can be reproduced following up to 15 % fractional crystallization through the removal of an olivine (+Cr-spinel)-dominated cumulate, while chassignites experienced between 20 to 30 % of fractionation. The preservation of magmatic signatures in sulfide HSE compositions allows for an in-depth reconstruction of the evolution of the nakhlite-chassignite parental melt composition.
SN - 0016-7037
SN - 1872-9533
ER -