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Traversella 矽卡岩发育于 Traersella 闪长岩体接触变质带,应用相平衡原理确定早期矽卡岩阶段的温度为625～550℃,晚期为525～300℃.不同类型的矽卡岩中稀土元素含量高于相应的原岩.所有内矽卡岩带的岩石具相似的轻稀土分异和无 Eu 异常的分布形式,表明原始交代流体具有类似的稀土模式.与早期矽卡岩平衡的水的δ~(18)O 为8.3～8.9‰;晚期氢氧化物化阶段开始时流体的δ~(18)O 与早期流体的相当,但后来则迅速下降(8.0‰→5.0‰),硫化物阶段流体的δ~(18)O 进一步降低(5.0‰→3.0‰).早期矽卡岩中硅酸盐矿物的 I_(Sr)变化于白云质大理岩的值(0.70874-0.70971)和侵人体的值(0.70947～0.71064)之间,晚期则逐渐上升到0.71372.早期交代流体的稀土模式不能确定流体的来源,而同位素则显示早期高温交代流体与闪长岩达到了同位素平衡,这暗示着早期流体不是从结晶侵入体中分离出来的就是原来与侵入体平衡的变质水.氧、锶同位素表明晚阶段含水矿物取代无水矿物是由于与大气降水的混合.
The Traversella Skarn developed in the metamorphic zone of Traersella diorite body. The phase equilibrium principle was used to determine the temperature of Early skarn stage from 625 ℃ to 550 ℃ and the late stage from 525 ℃ to 300 ℃. The REE content of different types of Skarn Higher than that of the corresponding protoliths.All the inner skarn zones have similar light rare earth differentiation and Eu-anomalous distribution patterns, indicating that the original metasomatism fluid has a similar RE pattern.δ of water equilibrated with the early skarn The δ 18 O of the fluid at the beginning of the late stage of hydration is the same as that of the early fluid but decreases rapidly from 8.0 ‰ to 5.0 ‰ at the beginning of the late stage of hydration. The δ_ (18) O decreases further (5.0 ‰ → 3.0 ‰). The changes of I_ (Sr) of silicate minerals in early skarn over the value of dolomitic marble (0.70874-0.70971) and intrusion body (0.70947 ~ 0.71064), while the late stage gradually rose to 0.71372. The early replacement fluids did not determine the source of fluids, whereas the isotopes showed that isotopic equilibrium between early high temperature fluids and diorites was reached, suggesting that the early fluid did not crystallize from the crystalline Invaded the body isolated The original and the intrusion of water balance deterioration. Oxygen and Strontium isotopic substitution late stage aqueous mineral show anhydrous mineral is mixed with the atmosphere due to the precipitation.