| 变质作用精细过程研究进展 |
| |
| 引用本文： | 吴春明,耿元生.变质作用精细过程研究进展[J].地球科学进展,2001,16(6):785-794. |
| |
| 作者姓名： | 吴春明 耿元生 |
| |
| 作者单位： | 中国地质科学院地质研究所, |
| |
| 基金项目： | 国家自然科学基金项目“阿拉善地区早前寒武纪变质岩的变质作用演化” (编号 :40 0 0 2 0 17)，“吕梁地区古元古代末花岗岩
对吕梁运动的制约”(编号 :40 0 72 0 6 0 )，中国地质调查局项目“中国北方若干重点前寒武纪区构造—岩石—地层—年代学
格架”(编号 :J2 1 4 |
| |
| 摘 要： | 主要总结了最近 5年以来，国内外在变质作用精细过程研究若干方面的进展：人们在更细微尺度上，对矿物成分环带、成分梯度等矿物微区成分变化情况有了更深入的研究；发现矿物中不同化学组分抵御变质峰期后降温过程的能力不同；利用矩阵奇异值分解等数学方法定量探讨矿物（组合）之间是否存在质量平衡关系，进而判断矿物（组合）之间的平衡-非平衡关系；开始尝试恢复变质峰期后发生分解反应或纯转换反应的变质高峰期矿物的原始成分；出现了不依赖于矿物热力学数据和矿物活度模型的高精度相对温压计；补偿规则引入了矿物速率计，速率计计算结果更直观；最近发展的 Ms sbauer谱新技术，可以在小至50×30μm2的区域里实现铁镁质矿物原位（insitu）Fe 3＋含量的分析；使用激光探针等离子体质谱法、激光探针 40 Ar／39 Ar法、电子探针测年法、二次离子质谱法等新方法，实现对常见变质矿物的原位定年，使得变质作用较完整过程的连续定年成为可能。今后的发展方向至少有四个方面：深化并且充分利用已有的矿物微区成分分析方法和放射性微区测年方法，洞悉变质过程中的各种微观-超微观现象，探讨变质反应速率；研究不同大地构造环境的变质作用特征；实施大量的高精度矿物相平衡逆转实验，以获取高精度矿物热力学数据，进一步发展矿物固溶体热力学；采用岩石学实验模拟岩石变质过程，深入研究变质反应动力学。
|
| 关 键 词： | 变质作用 平衡-非平衡关系 矿物中Fe3＋含量 矿物原位定年 |
| 文章编号： | 1001-8166(2001)06-0785-10 |
| 收稿时间： | 2001-03-13 |
| 修稿时间： | 2001-08-22 |
SOME RESEARCH ADVANCES ON DETAILED METAM-ORPHIC PROCESS IN THE LAST FIVE YEARS |
| |
| WU Chun ming,GENG Yuan sheng.SOME RESEARCH ADVANCES ON DETAILED METAM-ORPHIC PROCESS IN THE LAST FIVE YEARS[J].Advance in Earth Sciences,2001,16(6):785-794. |
| |
| Authors: | WU Chun ming GENG Yuan sheng |
| |
| Institution: | Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China |
| |
| Abstract: | In the past five years, some research advances of detailed metamorphic process is reviewed, in the following aspects:（1）chemical zoning and chemical gradient of metamorphic minerals on mm-μm scales were carefully investigated;（2）it was discovered that different elements of minerals have different abilities in resisting post-peak cooling;（3）singular value decomposition (SVD) was adopted to quantitatively judge mass equilibrium relationships, and later, to decipher the equilibrium disequilibrium thermodynamic relationships, between assemblages of minerals;（4）the original chemical composition of minerals involved in post-peak decomposition or net transfer reaction was tried to regain;（5）the concept and method of high precision relative geothermobarometry, which is not dependent on thermochemical data or activity-composition relations of minerals involved, was developed;（6）compensation law was introduced to geospeedometry, and thus the cooling rate-time relation may be directly displayed;（7）the newly developed technique of M-ssbauer milliprobe was used to determine in situ Fe3+ contents of minerals in an area as small as 50×30 μm2;（8）LP-ICPMS, 40Ar/39Ar laser-probe, electron microbe, and secondary ion mass spectrometry (SIMS) were developed to determiner in situ radioactive ages of minerals, thus continuous dating of a complete metamorphic process is possible. In the near future, the following work should be done: (a) to refine and adopt the advanced methods and instruments mentioned above, in order to investigate the various aspects and determine the speed of metamorphism;（b）to study on and summarize the characteristics of metamorphism of rocks from different tectonic terranes; (c) to do a great number of reversed equilibrium experiments on minerals, and derive high-precision thermochemical data, and to have better understanding of mixing properties of the relevant minerals;（d）to model the metamorphic process via petrological experiments, and to provide insights into metamorphic dynamics. |
| |
| Keywords: | Metamorphic process Equilibrium disequilibrium Fe 3+ content In situ dating |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《地球科学进展》浏览原始摘要信息 |
| 点击此处可从《地球科学进展》下载免费的PDF全文 |
|
