榴辉岩形成过程中石榴石生长的实验研究  

EXPERIMENTAL INVESTIGATION ON THE GARNET GROWTH DURING THE METAMORPHISM OF ECLOGITE FACIES

作　　者：周文戈[1] 谢鸿森[1] 赵志丹[2] 郭捷[1] 徐济安[3] 白武明 

机构地区：[1]中国科学院地球化学研究所深部室,贵阳550002 [2]中国地质大学(北京) [3]台北中央研究院地球科学研究所,台北11529 [4]中国科学院地球物理研究所地球动力学开放实验室,北京100101

出　　处：《高压物理学报》1999年第4期241-246,共6页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金资助!( 49672 0 99;497742 35 )

摘　　要：在2.0～3.0GPa、860～980℃、加温时间0.57～13.07h的条件下,研究了粗面玄武岩、安山岩—榴辉岩相变过程中的石榴石生长。这一过程中的石榴生长为正常晶体生长。石榴石粒径随时间而增大,其生长速率随粒径增大而减小。粗面玄武岩—榴辉岩相变过程中的石榴石生长速率大于安山岩—榴辉岩相变过程中的石榴石生长速率,实验样品的初始化学成分及挥发份含量的不同造成了这一差别。在变质作用初期,界面是控制晶体生长的主要因素。The grain growth kinetics of the garnet during the transformation of trachybasalt and andesite to eclogite has been investigated at 2.0～3.0GPa.The experimental samples were annealed at temperatures of 860℃,870℃and 980℃for 0.57 to 13 hours.The grain size was determined optically.The normal grain growth of the garnet during the metamorphism of eclogite facies was observed.The grain growth of the garnet increases with increasing annealing time.The rate of the garnet growth decreases with increasing the grain size.However,the rate of the garnet growth during the trachybasalt eclogite transformation is more rapid than that of the garnet growth during the andesite eclogite transformation.This phenomenon is attributed to the differences of the chemical compositions and the volatile contents between the trachybasalt and the andesite.In the early stage of the metamorphism of the eclogite facies,the interface controlled mechanism dominates in the garnet growth.

关 键 词：粗面玄武岩 榴辉岩 石榴石生长 晶体生长 

分 类 号：P588.145[天文地球—岩石学]