Viscosity of Evolving Magmas: A case study of the Glass House Mountains, Australia

被称为玻璃屋山（GHM）的火山说明了一系列由岩浆房分离结晶产生的岩浆组成，该岩浆房与2600万年前澳大利亚大陆越过地幔柱有关。关于这些岩浆的就位或岩浆房的温度的信息很少。作为解决玻璃屋山火山塞的出现和岩浆房中发生的过程的第一种方法，将确定不同岩浆成分的粘度。该系列的组成提供了一个教科书的情况下进行分离结晶和排放岩浆房粘度的测定。玻璃屋山岩浆的流变性将在高粘度条件下使用微渗透技术确定。将使用热容数据和粘度与构型熵和温度之间的Adam-Gibbs关系将粘度外推至低粘度条件。

The volcanoes known as the Glass House Mountains (GHM) illustrate a compositional series of magmas produced by fractional crystallisation of a magma chamber which is associated with the Australian continent passing over a mantle plume 26 million years ago. There is little information on the emplacement of these magmas or the temperature of the magma chamber. As a first approach to addressing the occurrence of the Glass House Mountains volcanic plugs and the processes occurring in the magma chamber, the viscosity of the different magma compositions will be determined. The compositional series provide a textbook case for the determination of viscosity of a magma chamber undergoing fractional crystallisation and discharge. The rheology of the Glass House Mountains magmas will be determined at high viscosity conditions using the micro-penetration technique. The viscosities will be extrapolated to low viscosity conditions using heat capacity data and the Adam-Gibbs relationship between viscosity and configurational entropy and temperature.