火山碎屑岩分类评述及火山沉积学研究展望

火山碎屑岩是介于熔岩和沉积岩之间的过渡类型岩石，岩类复杂。长期以来，火山碎屑岩的分类研究受到了国内外学者的重视，先后提出了火山碎屑物、火山碎屑岩岩性和火山碎屑岩成因分类。虽然目前国际地科联火成岩分类命名委员会确定的火山碎屑物和火碎屑岩岩性分类已得广泛推广，但此分类尚有不足之处。中国学者提出的火山碎屑岩分类时间较早，有自己特色，在一定的范围得到了应用。在此基础上，本文提出了新的火山碎屑物、火山碎屑岩岩性和火山碎屑岩成因分类。火山沉积作用是介于火山学和沉积学之间的边缘研究领域。近20年来，火山沉积作用研究在理论和方法上得到了深化，火山喷发和沉积的物理作用及实验和数值模拟已经成为未来发展的趋势。尽管这样，野外地质和火山碎屑岩的岩性特征，仍是火山碎屑岩成因研究的基础。

Classification of Pyroclastic Rocks and Trend ofVolcanic Sedimentology: A Review

Pyroclastic rocks are a kind of transitional and complex rocks between lavas and sedimentary rocks. Petrologists,both at home and abroad have spent a lot of time on the classification of pyroclastic rocks, and suc_cessively put forward the classification of pyroclasts, the petrographic and the petrogenetic classification of pyroclasic rocks. Widely accepted as they are, the classification of pyroclasts and the petrographic classification of pyroclastic rocks stipulated by the IUGS Subcommission on the Systematics of Igneous Rocks fail to consider the classification with Chinese characteristics, which was put forward in 1950s to 1960s and improved in 1980s to 1990s and has since been widely used in China. On the basis of the past schemes, new classifications of pyroclasts and the petrographic as well as the petrogenetic classification of pyroclastic rocks are proposed in this paper. Volcanic sedimentation is a frontier realm between volcanology and sedimentology. The past twenty years have witnessed great development in the study of volcanic sedimentation, both theoretical and methodological. The dynamics, experimentation and simulation of volcanic eruption and sedimentation have become the main trend in the future. Despite of this, the field geology and the character of pyroclastic rocks remain the basis of the petrogenesis of pyroclasic rocks.