PM normalized

[r]

Ainsi, l’Hf de BD2 a probablement été affecté par une mobilité secondaire qui aurait aussi contribué à ce que son e Hf (T) soit anormal. Cette conclusion

Red lines indicate FeO and MgO contents of accumulated fractional melts of depleted peridotite at the melt fractions F shown [Herzberg and O’Hara, 2002].. Green arrows illustrate

(a) and (b) Photomicrographs of massive black cherts from the top of the Buck Reef sequence: microbial mat structures are absent and the chert consists of a

[r]

Simply stated, the spinifex paradox refers to the presence, at depths within a komatiite flow where cooling rates must have been low, of elongate skeletal crystals whose

Pigeonite is absent from the uppermost part of a komatiite flow, but appears deeper down in komatiite flows in slowly cooled cells enclosed by large platy olivine

Their chemical characteristics are qualitatively similar, though not so extreme, as those of kimberlites (high MgO is combined with low SiO 2 and Al 2 O 3 and high concentrations