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西天山的基性高压变质岩显示互相连接的榴辉岩相脉体网络来源于蓝片岩的进变质脱水作用,通过这些网脉可以洞察在俯冲带高压条件下远程流体流动中的流体-岩石相互作用和元素负载。岩相学证据表明外来流体的渗透作用产生运输脉,而流体持续的沟道式流动导致主岩蓝片岩的淋滤。脉和蓝片岩蚀变带中锂(Li)的含量几乎是蓝片岩主岩中锂的两倍,它支持流体是外部来源的设想。这些流体触发了蓝片岩主岩的榴辉岩化作用而形成蓝片岩蚀变带。由于成脉流体中的微量元素含量低,所以导致与流体发生化学反应的主岩中所有微量元素的强烈淋滤。在此过程中有53%~81%的微量元素被活化,与大离子亲石元素和轻稀土元素的损失相符合,它们的损失量几乎是重稀土元素和高场强元素损失量的两倍。
The basic high-pressure metamorphic rocks in the western Tianshan show that the interconnected eclogite veins are derived from the metamorphic dehydration of the blue schist which can be used to gain insight into the fluid-rock interaction in the remote fluid flow under high pressure in the subduction zone Role and element load. Petrographic evidence suggests that the infiltration of foreign fluids produces transport veins, and the continuous channeling of fluids leads to leaching of the host rock blue-lithofacies. Lithium (Li) in the vein and blueschist alteration zone is almost twice as high as Lithium in the main lithofacies, and it supports the idea that the fluid is an external source. These fluids triggered the eclogite lithification of the main lithofacies to form the blue-schist alteration zone. Due to the low content of trace elements in the veins fluid, strong leaching of all the trace elements in the host rock, which chemically react with the fluid, results. During this process, 53% to 81% of trace elements are activated, consistent with the loss of large ion lithophile and light rare earth elements, which are almost twice the loss of heavy rare earth elements and high field strength elements .