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火山岩中矿物的成分环带中蕴含着其生长过程中岩浆成分和温压等物理状态的变化信息,对研究岩浆演化和火山喷发动力过程非常重要.长白山天池火山气象站期碱流岩辉石具有明显的环带结构,其成因尚未讨论.本文通过了辉石环带的电子探针分析,发现MgO和Na_2O等元素的相对含量呈剧烈的振荡形态.同时,利用非线性时间序列分析的方法,对MgO元素沿辉石环带成分进行了相空间重构的探索性研究.结果发现,辉石环带成分时间序列的相空间吸引子为混沌吸引子.这说明辉石斑晶在生长时所处的系统具有高的自由度和高度的复杂性,其结晶和生长时周围岩浆的成分是高度非稳态和不平衡的.我们认为是岩浆房补给混合和热对流作用过程导致辉石所处的岩浆成分在高MgO、低MgO之间激烈振荡变化,形成了辉石环带成分的剧烈振荡.而这些补给-混合-对流的过程可能最终导致岩浆房超压而发生溢流喷发.
The composition of mineral in the volcanic rock belt contains information on the changes of physical conditions such as magma composition and temperature and pressure during its growth and is very important for the study of magmatic evolution and volcanic eruption dynamic process. The obvious structure of the ring zone has not been discussed yet.In this paper, the electronic probe analysis of the pyroxene ring zone shows that the relative contents of MgO and Na2O are in the form of violent oscillations.Using the method of nonlinear time series analysis, The exploratory research on the phase space reconstruction of the pyroxene zone of MgO elements shows that the phase space attractor of the pyrite ring component time series is a chaotic attractor, The system has a high degree of freedom and a high degree of complexity, the composition of the surrounding magma during its crystallization and growth is highly unstable and unbalanced, and we believe that the magma chamber replenishment mixing and thermal convection lead to the presence of pyroxene Of the magmatic components oscillate violently between high MgO and low MgO, resulting in violent oscillations of the pyroxene ring components, and these recharge-mix-convection processes may eventually lead to Overpressure in magmatic chamber and overflow eruption occurred.