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科学观测表明在敛聚型和离散型板块边界大量挥发份和金属通过去气作用从岩浆分离而进入陆相和海底火山热液系统。以ＣＯ２为主的流体伴随着挥发份贫乏的洋脊型玄武质岩浆作用而形成，其岩浆产生于洋脊之下的地幔的部分熔融过程。与此对照，丰富的、以Ｈ２Ｏ为主的流体产生于富含挥发份的火山弧型岩浆的去气作用，这种岩浆的起源与俯冲洋壳的脱水过程有关。岩浆流体常由各种挥发份（如Ｈ２Ｏ，ＣＯ２，ＣＯ，ＳＯ２，ＨＣｌ，Ｈ２Ｓ，ＨＦ，Ｈ２，Ｎ２，ＣＨ４，Ａｒ，Ｈｅ等）和含量不等的金属（如Ｎａ，Ｋ，Ｃａ，Ｆｅ，Ｃｕ，Ｐｂ，Ｚｎ，Ａｕ，Ｍｏ，Ｒｅ，Ｉｎ，Ｗ等）组成。受挥发份在熔体中的溶解度制约，由岩浆去气作用形成的最初流体相主要为ＣＯ２，而后来形成的流体相较富含Ｈ２Ｏ。随着温度的降低，一个常伴随着由长英质岩浆演化而形成的ＣＯ２和Ｈ２Ｏ混合的岩浆流体可能因不混溶作用而分离成一个低盐度（低密度）的气相和一个高盐度（高密度）的液相。在一个流体熔浆体系中，许多成矿金属强烈地分配在流体相中，并且在该流体分离出岩浆时被其带出。这些金属主要以氯化物和硫化物的络合物形式被气相和液相携运———气相携运受支配于其挥发性；热液携运受其溶解度所制约。岩浆流体可提供大?
Scientific observations have shown that large amounts of volatiles and the metal at the convergent and discrete plate boundaries separate from the magma by de-aeration and enter the continental and submarine volcanic hydrothermal systems. The CO2-dominated fluid is formed by the depletion of the evaporite ridge-type basaltic magma, and its magma is generated by the partial melting of the mantle below the ridges. In contrast, the abundant H2O-dominated fluid results from the degassing of volcanic arc-rich magmas rich in volatile matter, the origin of which is associated with the dehydration of subducted oceanic crust. Magmatic fluids are often composed of volatile components (such as H2O, CO2, CO, SO2, HCl, H2S, HF, H2, N2, CH4, Ar, He etc.) and metals with different contents (such as Na, K, Ca, Fe , Cu, Pb, Zn, Au, Mo, Re, In, W, etc.). Due to the solubility of the volatile in the melt, the primary fluid phase formed by the magma degassing is mainly CO2, whereas the fluid formed later is more H2O-rich. As the temperature decreases, a magmatic fluid, often accompanied by a mixture of CO2 and H2O formed by the evolution of the mafic magma, can segregate into a low salinity (low density) gas phase and a high salinity (High density) liquid phase. In a fluidic slurry system, many metallogenic metals are strongly distributed in the fluid phase and are carried out as the fluid separates the magma. These metals are mainly carried in the gas and liquid phases in the form of complexes of chlorides and sulfides - the vapor phase transport is governed by their volatility; the transport of hydrothermal fluids is governed by their solubility. Magma fluid can provide large?