| 摘要: |
| 稀土元素所具有的内潜同晶现象,可将其14个元素则可视为一个元素,而其它稀土元素视为其同位素,其在地质作用过程中,将像同位素一样,存在分馏。按照同位素的分馏模式,以球粒陨石值作为标准,计算出每一个稀土元素的分馏值,其值按δREE=[(REE/ΣREE)样品/(REE/ΣREE)球粒陨石-1]×100计算,以此为纵坐标,以原子序数为横坐标,作一个模式图,这种模式图称为稀土元素内潜同晶分馏模式图。该模式图在岩石成因,特别是岩浆岩的成因、岩浆岩的演化等方面有其独特的意义。 |
| 关键词: 稀土元素 内潜同晶现象 分馏模式图 类比倍比关系 百分偏差 |
| DOI： |
| 附件 |
| 投稿时间：2001-03-05 |
| 基金项目: |
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| The incomplete isomorphous REE fractionation models and their implications for the origin and evolution of magmatic rocks |
| LI Sheng, XU Yong-sheng |
| (Chengdu Institute of Geology and Mineral Resources, Chengdu 610082, Sichuan, China) |
| Abstract: |
| The incomplete isomorphism is a special type of isomorphous replacement for REE. An incomplete isomorphous REE fractionation models are presented herein. In these models, fourteen elements of REE are postulated to be considered as one element, whereas the others as isotopes. These elements can be fractionated in geological processes. According to these models, the fractionation values of each REE can be calculated with respect to chondrite-normalized values. The formula for calculation is δREE=[(REE/ΣREE)sample/(REE/ΣREE)chondrite-1]×100. The modal diagrams then may be constructed by using the calculated values as y-coordinate and atomic numbers as x-coordinate. The modal diagrams are well referred to as the incomplete isomorphous REE fractionation models cited above, and will improve our knowledge of petrogenesis, especially of the origin and evolution of magmatic rocks. |
| Key words: REE incomplete isomorphism fractionation model analogy/multiplication percentage deviation |
