火山射气岩浆喷发作用研究进展

Study pregress on volcanic phreatomagmatic eruption.

射气岩浆喷发是一种特殊类型的火山活动,水在这类火山活动中起到至关重要的作用,且其喷发产物——低平火山口和基浪堆积物在我国乃至全世界都有广泛的分布。国际上对射气岩浆喷发的研究始于1921年,迄今为止已有80余年的历史。国内外许多学者运用火山地质学、岩石学、沉积学、物理火山学及数值模拟等多学科研究手段,对射气岩浆喷发作用及其产物进行详细的野外观测描述,并探讨其成因机制。本文在前人研究基础上,以我国南方北部湾周边第四纪火山区大量存在的射气岩浆喷发成因的低平火山口和基浪堆积物为研究对象,深入讨论了基浪堆积物的地质特征、射气岩浆喷发形成的基本条件、喷发过程的动力学机制以及基浪流的搬运过程等几方面重要问题,并对已有的研究成果进行了概括和总结,提出有待解决的难点,揭示了这类火山活动特有的属性。

As an essential and important type of volcanic activity on earth, phreatomagmatic eruption is characterized by groundwater-related explosive eruption and subsequent base surge deposit and maar lakes. Base surge deposit and maar lakes are widely distributed all over the world, and also in the Northeast China and the southern China. Study of phreatomagmatic eruption maybe dated back to 1921, and in the following over 80 years, many works have been done on phreatomagmatic eruption, using various of methods of volcanic geology, petrology, sedimentology, physical volcanology and digital modeling, to discuss its origin and mechanism. In this paper, we focuse on the maar lakes and base surge deposits of the phreatomagmatic eruptions in the Beibuwan district, southern China. Our research includes the geological feature, transportation and sedimentation model of the base surge deposit, the origin, mechanism and dynamics of the phreatomagmatic eruption. We generalized the past researching production to discover the special property of this type volcanic activity, promoting the study level about this area in our country.