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本区夕卡岩的稀土元素(REE)分布模式表现为富集轻稀土元素(LREE)的直线型和以Ce、Pr或Nd为峰值的折线型。夕卡岩全岩中REE分布模式基本上受石榴子石中REE的分配行为控制。石榴子石富集LREE可能是承袭形成它们的初始物中REE丰度和分配行为的反映。石榴子石中REE(尤其是La)分布的不均匀性、石榴子石微裂隙及包裹体中REE的丰度可能是导致直线型和过渡型REE分布模式的主要原因。石榴子石中折线型REE分布模式可能受石榴子石晶体化学和晶体结构的控制。具有这种REE分布模式的钙铁-钙铝榴石可能代表相对平衡条件下岩浆结晶分异产物。
The REE distribution pattern of skarn in this area is characterized by a linear type enriched in LREE and a polygonal type with peak in Ce, Pr or Nd. The REE distribution pattern in the whole skarn rock is basically controlled by REE distribution in garnet. The enrichment of LREEs by garnet may be a reflection of the abundance and distribution of REE in the starting materials that formed them. The inhomogeneity of REE (especially La) distribution in garnet, micro-fissures of garnet and the abundance of REE in inclusions may be the main reason for the linear and transitional REE distribution patterns. The polygonal REE distribution pattern in garnet may be controlled by garnet crystallography and crystal structure. Calcium-iron-garnet with this REE distribution pattern may represent the differential crystallization of lava crystals under relative equilibrium conditions.