|
|||||
|
|
| 变质作用高峰期后的离子再交换与纯转换反应及对温度压力计算的影响 | |
| 引用本文： | 符巩固,陈广浩,吴春明.变质作用高峰期后的离子再交换与纯转换反应及对温度压力计算的影响[J].矿物岩石地球化学通报,2004,23(4):362-367. |
| 作者姓名： | 符巩固 陈广浩 吴春明 |
| 作者单位： | 1. 中国科学院,广州地球化学研究所,广州,510640;中国科学院,研究生院,计算地球动力学重点实验室,北京,100039;湖南省地质调查院,长沙,410011 2. 中国科学院,广州地球化学研究所,广州,510640 3. 中国科学院,研究生院,计算地球动力学重点实验室,北京,100039 |
| 基金项目： | 国家自然科学基金资助项目(40002017) |
| 摘 要： | 变质程度达角闪岩相及麻粒岩相的各类变质岩石在变质作用高峰期后，如果降温速率比较慢，往往发生退变质性质的离子再交换反应与纯转换反应。这两类退变质反应不可避免地改造了变质高峰期的矿物成分，使岩石不能准确记录变质作用各阶段的矿物成分和变质作用p-T轨迹。对这两类反应的研究已成为近年来变质岩石学研究的热点之一。本文通过研究实例，简要综述了基性麻粒岩中石榴子石-斜方辉石之间的Fe-Mg再交换反应、酸性麻粒岩中斜长石-碱性长石之间的K-Na再交换反应、泥质片麻岩中石榴子石变斑晶边部的部分分解(纯转换)反应，以及恢复变质高峰期矿物成分和计算变质高峰期p-T条件的方法。指出只有在准确恢复变质高峰期变质矿物成分的基础上，获得的变质作用p-T-t轨迹才能反映客观地质事实。 |
| 关 键 词： | 变质作用 矿物成分 麻粒岩相 退变质 变质岩 石榴子石 p-T轨迹 高峰期 反应 影响 |
| 文章编号： | 1007-2802(2004)04-0362-06 |
| 修稿时间： | 2004年2月23日 |
The Effects of Post-Peak Retrograde Ion-Exchange and Net Transfer Reactions on the Calculated Temperatures and Pressures |
|
| FU Gong-gu.The Effects of Post-Peak Retrograde Ion-Exchange and Net Transfer Reactions on the Calculated Temperatures and Pressures[J].Bulletin of Mineralogy Petrology and Geochemistry,2004,23(4):362-367. | |
| Authors: | FU Gong-gu |
| Institution: | FU Gong-gu~ |
| Abstract: | If the cooling rate is sufficiently low, retrograde post-peak ion-exchange reactions and/or net transfer reactions may occur in amphibolite facies and higher grade rocks. Such retrograde reactions may inevitably change the compositions of peak minerals and therefore retrieving the peak p-T conditions and p-T-t paths becomes a difficult work. This paper summaries three typical studies on the retrograde ion-exchange and net transfer reactions during the post-peak cooling, including Fe-Mg re-equilibration between garnet and orthopyroxene in mafic granulites, K-Na re-equilibration between plagioclase and alkali feldspar in felsic granulites and net transfer reactions in amphibolite facies metapelites. Meanwhile, the methods of recovering the peak mineral compositions and peak p-T conditions are also introduced. It is believed that only after the work of retrieving peak mineral compositions be done, should we obtain reliable p-T-t paths for higher grade metamorphic rocks. We also admit that such a task is not always straightforward and some complex conditions may be encountered in studying metamorphic carbonates and metamorphic felsic rocks. |
| Keywords: | retrograde ion-exchange reaction retrograde net transfer reaction peak-composition recovery metamorphic conditions p-T-t path |
| 本文献已被 CNKI 维普 万方数据 等数据库收录！ | |