- 责任者：Yu Hongmei (Institute of Geology ; China Earthquake Administration ; Beijing 100029 ; China) ; Xu Jiandong
- 刊名：Seismology and Geology
- 出版年：2011
- 卷期：33(2)
- 关键词：火山碎屑岩 ; pyroclastics ; 火山喷出物 ; ejecta ; 长白山 ; Changbai Mountains
- 页码：p.440-451
- 图表：8 illus., 4 tables, 30 refs.
- 分类号：1400
- issnNo：ISSN0253-4967
- isbnNo：CN11-2192/P
The shape parameter of particles is an important parameter in the formula of the terminal settling velocity, but it was usually assumed to be spherical or ellipsoidal without detailed study. According to the morphological characterization of the tephra particles erupted during the Millennium eruption of Changbaishan-Tianchi volcano, the authors got some new recognition: the tephra particles consist mainly of pumice, which have irregular shapes, varying from very equant to elongate and from subround angular. The results show clearly that the morphology of particles influences strongly both the terminal settling velocity and dispersal range, and hence should be fully considered when simulating tephra dispersion and forecasting disasters in the future.