Investigation of deep fluid using maluti-solid-phase inclusions

由斜黝石(Czo) + ky + qz组成的多固相包裹体（msi）在吉尔吉斯斯坦Makbal杂岩的石榴石和变尖石基体中被发现。msi的重构成分与lawsonite （Lws）一致。岩石学研究表明，Lws在UHP阶段（约3 GPa和550C）稳定，在1.6 GPa和550C等温减压时分解为msi。msi中Czo颗粒的微量元素特征表现为扁平的稀土球粒归一化模式，与Lws的典型稀土模式相同。因此，石榴石中含有的msi中Czo的REE含量可能继承于前Lws，因为分解反应与基体分离。在等温减压阶段，Lws分解和czo形成反应伴随着流体的释放，这意味着流体不仅可以在俯冲过程中产生，也可以在冷俯冲环境下超高压岩石的发掘过程中产生。

Multi-solidphase inclusions (MSIs) composed of clinozoisite (Czo) + ky + qz have been found within garnets and in the matrix of metapelits from the Makbal complex in Kyrgyz. The reconstructed compositions of MSIs are consistent with lawsonite (Lws). Petrological study showed that Lws was stable at UHP stage (ca. 3 GPa and 550C) and decomposed to the MSIs during isothermal decompression around 1.6 GPa and 550C. Trace element characteristics of Czo grains in the MSIs show a flat REE chondrite-normalized pattern, identical to the typical REE pattern of Lws. Thus, the REE content of Czo in the MSIs included in garnet was likely inherited from the former Lws as the decomposition reaction took place isolated from the matrix. Lws decomposition and Czo-forming reactions accompany fluid release during the isothermal decompression stage, implying that the fluids can be generated not only during subduction, but also during exhumation of UHP rocks in cold subduction settings.