A Simple Procedure for Measuring Magma Rheology
A Simple Procedure for Measuring Magma Rheology
复制标题
DOI：
10.20965/jdr.2019.p0616
复制
发表时间：
2019-06-01
影响因子：
0.8
通讯作者：
Ishibashi, Hidemi
中科院分区：
文献类型：
--
作者：
Kurokawa, Aika K.;Miwa, Takahiro;Ishibashi, Hidemi
在这项研究中，开发了一种在高温(>；1000摄氏度)下测量多相岩浆粘度的方法，该方法使用了一种简单的设备，该设备包括商用台式熔炉和粘度计。特别是，一次性容器的使用使得能够观察整个样品的微观结构。该方法被应用于1986年日本伊豆-大岛裂隙喷发的玄武岩安山岩岩浆。结果表明，获得了与前人研究一致的可靠数据，岩浆流变学随温度的降低而变得非牛顿，表现出明显的剪切变薄行为。基于三个简单的非牛顿流体模型，岩浆在1180℃时的流变性被定量地描述为剪切速率的函数。样品的剖面图证实，斜长石和Fe-Ti氧化物晶体几乎均匀地分散在样品中。0.14的平均晶体体积分数使晶体相互作用引起晶体排列的变化，影响了流变学。
In this study, a procedure to measure the viscosity of multi-phase magma at high temperatures (>1000 degrees C) was developed by using a simple apparatus comprising a commercially available desktop furnace and viscometer. In particular, the use of a disposable container enabled observations of the microstructure of an entire sample. The procedure was applied to basaltic andesite magma of the 1986 Izu-Oshima fissure eruption, Japan. The results show that reliable data, consistent with previous studies, were obtained and that the magma rheology became non-Newtonian with decreasing temperature, showing clear shear-thinning behavior. The theological properties of the magma at 1180 degrees C are quantitatively described as a function of shear rate based on three simple non-Newtonian fluid models. Sectional views of the sample confirm that plagioclase and Fe-Ti oxide crystals were nearly uniformly dispersed in the sample. The mean crystal volume fraction of 0.14 enabled crystal interactions inducing changes in crystal arrangement, affecting the rheology.