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The contents of REE tend to decrease from Ordovician to Tertiary strata wth the average inthe whole profile higher than that in the continental shell. REE distribution patterns in differentrock types of various periods display some similarities, though their absolute REE contens aredifferent from each other. All these rock types yield rightward declined V-shaped curves withnegative Eu anomalies. Thus, their REE distribution patterns are parallel to each other. In addi-tion, their REE parameters (δ Eu, Sm/Nd, ∑Ce/∑Y, and La/Yb) only vary over a narrow rangewith small devations. These features in REE stribution indicate a stabbe platform environmentduring sedimentation. The similarities in REE atterns since Palaeozoic imply a uniform chemicalevolution of the Phanerozoic crust.
The contents of REE tend to decrease from Ordovician to Tertiary strata wth the average inthe whole profile higher than that in the continental shell. REE distribution patterns in differentrock types of various cycles display some similarities, though their absolute REE contens are different from each other. These addendum patterns, their REE parameters (δ Eu, Sm / Nd, Σ Ce / Σ Y, and La / Yb) only vary over a narrow range with small devations. These features in REE stribution indicate a stabbe platform environmentduring sedimentation. The similarities in REE atterns since Palaeozoic imply a uniform chemicalevolution of the Phanerozoic crust.