首页> 外文期刊>Journal of Volcanology and Geothermal Research >Two new end members of pyroclastic density currents: Forced convection-dominated and inertia-dominated
【24h】

Two new end members of pyroclastic density currents: Forced convection-dominated and inertia-dominated

机译:火山碎屑密度流的两个新末端成员:强迫对流为主和惯性为主

获取原文
获取原文并翻译 | 示例
           

摘要

A great debate on the flow density of pyroclastic density currents (PDCs) in explosive eruptions has pervaded volcanology over the last decades (Dade and Huppert, 1996,1997; Wilson, 1997). PDCs consist of gas-particle flows that move for kilometers down the volcano and over the surrounding terrain. They are generated because of vertical collapse of an eruptive column (Woods, 1988; Valentine and Wohletz, 1989), or explosion of a lava dome/overpressure jet (blast) (Esposti Ongaro et al., 2008,2011), and they flow downstream as radial or unidirectional currents, respectively. Radial currents are also generated because of collapse of an overpressurized (mushroom-like expanded) column (Dellino et al., 2010a), pyroclastic fountaining (Woods and Wohletz, 1991; Clarke et al., 2002), or in ignimbrite-forming eruptions (Fisher et al., 1980; Cas et al., 2011). In this paper, a new subdivision of PDCs, forced convection-dominated and inertia-dominated, is proposed based on flow property. A simple PDC simulation, and field evidences reveal that forced convection-dominated flows may transport own density if they are continuously fed at source, favored by steep volcano, or channelized. Inertia-dominated flows may leak the density floating over topography.
机译:在过去的几十年中,关于火山爆发中火山碎屑密度流(PDCs)的流动密度的争论引起了火山学的广泛讨论(Dade and Huppert,1996,1997; Wilson,1997)。 PDC由气体颗粒流组成,这些气体流沿着火山向下移动数公里,并越过周围的地形。它们的产生是由于喷发柱的垂直坍塌(伍兹,1988;瓦伦丁和沃列兹,1989),或者是熔岩穹顶/超压射流(爆炸)的爆炸(Esposti Ongaro等,2008,2011)。下游分别作为径向或单向电流。由于过高压力(蘑菇状膨胀)柱的塌陷(Dellino等,2010a),热碎屑喷泉(Woods和Wohletz,1991; Clarke等,2002)或形成火成岩的爆发,也产生了径向电流。 (Fisher等,1980; Cas等,2011)。本文基于流动特性提出了一种新的PDC细分方法,即强制对流为主和惯性为主。一个简单的PDC模拟和现场证据表明,如果对流占主导地位的对流连续不断地从源头注入,受到陡峭的火山的青睐或形成通道,它们可能会传输自己的密度。以惯性为主的流动可能会泄漏漂浮在地形上的密度。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号