Abstract
We present clinopyroxene REE variations in certain peridotite xenoliths recovered from Malaita, Solomon Islands, to address the role of garnet during melting in a mid-oceanic ridge setting. On a Sm/Yb ratio versus Yb content diagram, the measured clinopyroxenes yield a significant deviation from the field of global abyssal peridotites toward higher Yb at given Sm/Yb, that can be recognized as strong garnet signature. However, most likely explanation for the deviation is subsolidus REE redistributions caused by changes of modal abundance ratio and REE partition coefficients between orthopyroxene and clinopyroxene. Thus, caution should be excercised while using clinopyroxene REE variation to address the melting history of peridotite.
