Density and size segregation in deposits of pyroclastic flow

被引：14

作者：

Mitani, NK ^{[1
]}

Matuttis, HG

Kadono, T

机构：

[1] Univ Tokyo, Earthquake Res Inst, Tokyo 1130032, Japan

[2] Univ Electrocommun, Dept Mech & Control Engn, Tokyo 1828555, Japan

[3] Japan Agcy Marine Earth Sci & Technol, Inst Res Earth Evolut, Kanagawa 2370061, Japan

来源：

GEOPHYSICAL RESEARCH LETTERS | 2004年 / 31卷 / 15期

关键词：

D O I：

10.1029/2004GL020117

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

The main portion in the deposits of pyroclastic flow shows various characteristic features such as density and size segregation of large fragments in the vertical direction. To understand the mechanism which produces these features, we numerically study granular flows on an inclined rough surface with impurities that are different in density and size from the matrix particles. The simulation shows the occurrence of density and size segregation of large impurities, and the impurities finally concentrate at the top and the bottom. Based on these results, we discuss the mechanism of the segregation. It is found that the behavior of impurities is governed by gravity, buoyancy and the viscosity of the randomly moving matrix.

引用

页码：L156061 / 4

页数：4

共 32 条

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