Fig. 4: Primitive-mantle normalised trace element diagrams of olivine separates and bulk kimberlite rocks.
From: Primordial neon and the deep mantle origin of kimberlites
Positive anomalies for Ta ( ± Nb) and Ti in olivine probably indicate inclusions of ilmenite ( ± spinel) in some olivine separates (see Supplementary Fig. S1). Positive anomalies of Pb and Sr coupled with flat HREE patterns are consistent with variable crustal contamination in some olivine separates. Beyond these differences, the patterns of olivine separates show similar shapes to those of their bulk kimberlite samples, which underpins a magmatic origin for the fluids trapped in olivine.
