Early martian mantle overturn inferred from isotopic composition of nakhlite meteorites Export

@article{citeulike:6053874, abstract = {The early stages of planetary differentiation are characterized by the formation of magma oceans, which crystallize from the base up1, 2. The final, iron-rich residues of crystallization are dense and therefore tend to sink into the mantle, whereas the deeper, magnesium-rich material tends to rise up3, 4. The resultant mantle overturn would have had a profound influence on the evolution of the planets3, 4, 5, 6. Such an event probably occurred on Mars, but its initiation, timing and geochemical consequences are poorly constrained. Here we use isotopic data for nakhlite meteorites—chunks of martian crust transported to the Earth—and numerical simulations to constrain the evolution of the early martian mantle. We interpret the isotopic composition of the meteorites as evidence for an episode that occurred relatively early in Mar's history, about 100 million years after the planet's formation, during which garnet was removed from material that rose up from the deep mantle. This episode implies large-scale reorganization in the martian mantle and thereby provides compelling support for overturn. We suggest that this event probably led to substantial re-melting in the deepest mantle, which may have influenced early martian processes such as the development of crustal dichotomy.}, author = {Debaille, V. and Brandon, A. D. and O/'Neill, C. and Yin, Q. Z. and Jacobsen, B.}, citeulike-article-id = {6053874}, citeulike-linkout-0 = {http://dx.doi.org/10.1038/ngeo579}, citeulike-linkout-1 = {http://dx.doi.org/10.1038/ngeo579}, day = {20}, doi = {10.1038/ngeo579}, issn = {1752-0894}, journal = {Nature Geoscience}, keywords = {differentiation, mantle\_convection, mars}, month = {July}, number = {8}, pages = {548--552}, posted-at = {2009-11-01 18:39:03}, priority = {2}, publisher = {Nature Publishing Group}, title = {Early martian mantle overturn inferred from isotopic composition of nakhlite meteorites}, url = {http://dx.doi.org/10.1038/ngeo579}, volume = {2}, year = {2009} }

TY - JOUR ID - citeulike:6053874 L3 - citeulike-article-id:6053874 N2 - The early stages of planetary differentiation are characterized by the formation of magma oceans, which crystallize from the base up1, 2. The final, iron-rich residues of crystallization are dense and therefore tend to sink into the mantle, whereas the deeper, magnesium-rich material tends to rise up3, 4. The resultant mantle overturn would have had a profound influence on the evolution of the planets3, 4, 5, 6. Such an event probably occurred on Mars, but its initiation, timing and geochemical consequences are poorly constrained. Here we use isotopic data for nakhlite meteorites—chunks of martian crust transported to the Earth—and numerical simulations to constrain the evolution of the early martian mantle. We interpret the isotopic composition of the meteorites as evidence for an episode that occurred relatively early in Mar's history, about 100 million years after the planet's formation, during which garnet was removed from material that rose up from the deep mantle. This episode implies large-scale reorganization in the martian mantle and thereby provides compelling support for overturn. We suggest that this event probably led to substantial re-melting in the deepest mantle, which may have influenced early martian processes such as the development of crustal dichotomy. IS - 8 JF - Nature Geoscience SN - 1752-0894 EP - 552 TI - Early martian mantle overturn inferred from isotopic composition of nakhlite meteorites PB - Nature Publishing Group VL - 2 SP - 548 KW - differentiation KW - mantle_convection KW - mars AU - Debaille, V AU - Brandon, AD AU - O/'Neill, C AU - Yin, QZ AU - Jacobsen, B PY - 2009/07/20/ UR - http://dx.doi.org/10.1038/ngeo579 ER -