Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5783398 | Geochimica et Cosmochimica Acta | 2017 | 88 Pages |
Abstract
The new results for NWA 856 are combined with other shergottite data and are compared to mixing and assimilation and fractional crystallization (AFC) models using depleted shergottite magmas and ancient Martian crust as end-members. The models indicate that the range of REE abundances and ratios, when taken in isolation, can be successfully explained for all shergottites by crustal contamination. However, no successful crustal contamination model can explain the restricted εNdI of â6.8 ± 0.2 over the wide range of Mg# (0.65-0.25), and corresponding trace element variations from enriched shergottites to depleted shergottites. The findings indicate that the origin of the long-term ITE-enriched signature in enriched shergottites and the geochemical variability seen in shergottites is not a result of crustal contamination but instead reflects ancient mantle heterogeneity.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
J. Ferdous, A.D. Brandon, A.H. Peslier, Z. Pirotte,