Silicon peridotites

Secondary alteration processes are also responsible for element deviations, particularly the strong depletion of calcium and sodium relative to aluminum in some abyssal peridotites, as well as part of the scattered variations of silicon, magnesium, calcium, and sodium. Serpentinized, orogenic and ophiolitic peridotites may also be strongly depleted in calcium and sodium. However, these samples are rare in the selected database for peridotite massifs, which includes only moderately serpentinized samples. 

Solar nebula fractionations A candidate for fractionation during solar nebula differentiation is the element silicon. Hart and Zindler (1986) showed that on a Mg/Si versus Al/Si plot mantle peridotites and chondritic meteorites plot on two quite... 

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