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流体包裹体的中等-显微构造分析、空间分布特点、形态、显微温度揭示了位于挪威斯勘的纳维亚加里东造山带的多期变形变质火山型多金属硫化物矿床的流体演化的部分过程。矿体和围岩均遭受了绿片岩相变质作用和四期变形作用。D_2和D_3期变质作用达到了峰期。到了D_4期变质作用减弱为低绿片岩相。D_2到D_4期的不同构造环境有明显不同的四种流体包裹体类型。其中赋存左D_2期石英脉裂隙愈合生长带中的原生包裹体(类型1)是唯一保存下来的与D_1、到D_3期矿质再活化和脉体生长有关的包裹体。所有赋存在愈合的裂隙中的后期包裹体均是次生包裹体。Ⅱ型次生包裹体不论其构造背景如何均产生于石英脉中,它们的形成时间均不能早于D_4期。类型Ⅰ、Ⅱ包裹体均经历D_4期到D_4期后普遍的破坏性爆裂事件。泄露和/或破裂的发生是由于在D_4期后伴随着迅速减压的区域性抬升形成的内部超高压造成的。两种爆裂期后包裹体(类型Ⅲ和Ⅳ)均有一致的气液比率。低温度(T_h=137~297℃)和低盐度(0~6.7重量百分比NaCl当量盐度)的特点。这两类包裹体可能记录了地壳抬升后大气降水的混入。
Meso - microstructural analysis, spatial distribution characteristics, morphology and microscopic temperature of fluid inclusions reveal the fluid evolution of the multistage metamorphic volcanic polymetallic sulphide deposits in the Navier - Caledonian orogenic belt in the Norwegian Eskantha Part of the process. Both the ore body and the surrounding rock suffered the metamorphism of greenschist and the deformation of the fourth stage. D_2 and D_3 metamorphism peaked. D_4 metamorphism weakened to low greenschist facies. There are four distinct types of fluid inclusions in different tectonic settings from D_2 to D_4. Among them, the primary inclusions (Type 1) in the fissure healing zone of quartz vein in the left D_2 period were the only inclusions that were preserved related to mineral reactivation and vein growth in D_1 and D_3. All late inclusions present in the healing fractures are secondary inclusions. Type II secondary inclusions occur in quartz veins regardless of their tectonic setting, and their formation time can not be earlier than D_4. Type I and II inclusions all experienced the common destructive burst events from D 4 to D 4. The occurrence of leaks and / or ruptures is due to the internal ultrahigh pressure developed following the regional uplift of rapid depressurization after D_4. The inclusions (type III and IV) have consistent gas-liquid ratios after both burst events. Low temperature (T_h = 137 ~ 297 ℃) and low salinity (0 ~ 6.7 weight percent NaCl equivalent salinity) characteristics. These two types of inclusions may record the mixing of atmospheric precipitation after uplifting of the crust.