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长白山地区新生代火山喷发可分为七大旋回21期。其中前5个旋回(16期)的喷发产物均以玄武质和粗面质熔岩类为主,后2个旋回(5期)主要为粗面质碎屑流及火山灰与碱性流纹质浮岩。在一定深度范围内,岩浆上升速度是稳定的,无挥发分出溶现象;但岩浆上升到地壳浅处时,则发生强烈的挥发分出溶现象,岩浆体积膨大,上升速度加快,并形成具有一定高度的火山喷发柱。按一定时距内火山连续喷发计算其喷发量,结果偏大;本文以火山喷出的固体物质数量为准,根据火山岩中矿物包裹体的激光拉曼光谱测定结果,求出火山喷出的总量,结果是切合实际的。在此基础上讨论了该区新生代火山喷发对环境的影响及其灾害。
The Cenozoic volcanic eruption in Changbai Mountain area can be divided into seven cycles of 21 cycles. Among them, the eruptions of the first 5 cycles (16 stages) are mainly basaltic and rough lava, while the last two cycles (stage 5) are mainly coarse debris flow and volcanic ash and alkaline rhagades rock. Within a certain depth range, the magma rising rate is stable and no volatile matter is dissolved out. However, when the magma rises to the shallow crust, strong volatilization and dissolution occur, the volume of magma expands and the rate of increase accelerates, A certain height of volcanic eruption column. According to the results of laser Raman spectroscopy of mineral inclusions in volcanic rocks, the total eruption volume of volcanic eruptions is calculated according to the amount of solid matter ejected from the volcano. The result is realistic. Based on this, the influence of the Cenozoic volcanic eruption on the environment and its disasters are discussed.