The volcanic explosivity index (VEI) is a scale used to measure the size of explosive volcanic eruptions. It was devised by Christopher G. Newhall of the United States Geological Survey and Stephen Self in 1982.

2022年8月5日 · The Volcanic Explosivity Index (VEI) is a scale that describes the size of explosive volcanic eruptions based on magnitude and intensity. The numerical scale (from 0 to 8) is a logarithmic scale, and is generally analogous to the Richter and other magnitude scales for the size of earthquakes.

With each step in the scale representing an explosivity increase of 10X, a VEI 5 is roughly ten times more explosive than a VEI 4. Two steps of the scale is an increase of 100X in explosivity. For example, a VEI 6 is roughly 100 times more explosive than a VEI 4.

火山爆發指數（Volcanic Explosivity Index，簡稱VEI）是1982年美國地質調查局（USGS）的克里斯·紐豪爾教授（Chris Newhall）和夏威夷大學馬諾阿分校的斯蒂芬·塞爾夫提出的量表，以噴出物體積、火山雲和定性觀測用來量度火山爆發的強烈程度。

火山爆发指数（Volcanic Explosivity Index，简称VEI）是1982年美国地质调查局的纽豪尔教授（Chris Newhall）和夏威夷大学马诺阿分校的斯蒂芬·塞尔夫提出的量表，以喷出物体积、火山云和定性观测用来量度火山爆发的强烈程度。

2022年12月26日 · A common scale for expressing the size of an explosive volcanic eruption is the VEI—Volcanic Explosivity Index. Eruption size can’t be determined by instruments, so this scale is based on a combination of measurements and observations.

火山爆發指數（Volcanic Explosivity Index，簡稱VEI）是1982年美國地質調查局（USGS）的克里斯·紐豪爾教授（Chris Newhall）和夏威夷大學馬諾阿分校的史蒂芬·塞爾夫提出的量表，以噴出物體積、火山雲和定性觀測用來量度火山爆發的強烈程度。

Volcanic Explosivity Index (VEI) is a numeric scale that measures the relative explosivity of historic eruptions. Volume of products, eruption cloud height, and qualitative observations (using terms ranging from "gentle" to "mega-colossal") are used to determine the explosivity value.

2022年2月4日 · （Volcanic Explosivity Index，简称VEI） 是1982年由火山学家提出的以喷出物体积与喷发柱高度来衡量火山爆发强烈程度的量表。 非爆炸性喷发的火山（如夏威夷群岛上的一些火山）VEI为0，爆炸性喷发的火山VEI从1到8，每增加1个单位，其释放的能量就增加1个量级，喷发 ...

The United States Geological Survey (USGS) provides a freely downloadable Volcanic Explosivity Index (VEI) that describes the size of an explosive volcanic eruption. You can access this table and link to the USGS Volcano Hazard website for further information.