中文摘要：

系统论述了扩张脊之下的洋壳增生模式、辉长岩地球化学特征及其对岩浆源区及岩浆过程的反映，总结了辉长岩在洋底环境和俯冲带中的变质作用及微量元素地球化学行为，并探讨了蛇绿混杂岩带中辉长岩的特点。对典型蛇绿岩的研究表明，在席状岩墙根部区域存在熔体透镜，来自地幔的岩浆在此贮存、分异。蛇绿岩中不同层位辉长岩的成分差异及结构、构造特点反映了该分异过程。辉长岩以及辉长岩中单斜辉石的地球化学特征可以反演岩浆的源区特征和岩浆分异、混合过程。辉长岩发生的洋底变质包括与洋脊附近热液对流相关的绿片岩相-麻粒岩相变质作用和与超镁铁岩蛇纹石化相关的异剥钙榴岩化作用。辉长岩在变质过程中不相容元素的活动性与温度、流体性质以及构造作用密切相关。

英文摘要：

Recent studies of ophiolitic and modern oceanic gabbro are reviewed in this paper with particular interest on gabbro.The melt lens at root zone of the sheeted dyke complex has been considered to have an important role in storage and differentiation of basaltic melt and in the accretion of the lower oceanic crust.The geochemistry of gab-bro and clinopyroxene in gabbro has been widely used to constrain the nature of magma source and its differentia-tion.The gabbros are affected by greenschist-granulite-faces ocean-floor metamorphism and rodingitization,which are related to hydrothermal circulation near spreading ridge and serpentinization of ultramafic rocks,respectively. In subduction zone,warm and cool subduction zones have been divided according to the p-t path,which reflect differences in metamorphic reactions occurring in subducting oceanic crust.The mobility of trace elements in meta-morphic oceanic crust is controlled by temperature,fluid and deformation.