What does the volcanic explosivity index measure?

The Volcanic Explosivity Index (VEI) is a scale that describes the size of explosive volcanic eruptions based on magnitude and intensity.

What is the highest volcanic explosivity index?

Biggest Volcanic Bangs

  1. Yellowstone eruption, 640,000 years ago (VEI 8)
  2. Huaynaputina, 1600 (VEI 6)
  3. Krakatoa, 1883 (VEI 6)
  4. Santa Maria Volcano, 1902 (VEI 6)
  5. Novarupta, 1912 (VEI 6)
  6. Mount Pinatubo, 1991 (VEI 6)
  7. Ambrym Island, 50 AD (VEI 6 +)
  8. Ilopango Volcano, 450 AD (VEI 6 +)

What is the volcanic explosivity index and how is it used?

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.

What is the magnitude of a volcanic eruption?

How Big are Volcanic Eruptions?

VEI Description Plume Height
1 gentle 100-1000 m
2 explosive 1-5 km
3 severe 3-15 km
4 cataclysmic 10-25 km

How useful is the volcanic explosivity index?

It is very valuable because it can be used for both recent eruptions that scientists have witnessed and historic eruptions that happened thousands to millions of years ago. The primary eruption characteristic used to determine the volcanic explosivity index is the volume of pyroclastic material ejected by the volcano.

What is explosivity?

Explosivity meaning Filters. (uncountable) The state of being explosive. noun. (countable) A measure of the extent to which a material is explosive.

What are the top 10 worst volcanic eruptions?

The Top Ten: Deadliest Volcanic Eruptions

  • Tambora, Indonesia. 1815. 92,000.
  • Krakatau, Indonesia. 1883. 36,417.
  • Mount Pelee, Martinique. 1902. 29,025.
  • Ruiz, Colombia. 1985. 25,000.
  • Unzen, Japan. 1792. 14,300.
  • Laki, Iceland. 1783. 9,350.
  • Kelut, Indonesia. 1919. 5,110.
  • Galunggung, Indonesia. 1882. 4,011.

What is the volcanic explosivity index VEI of a Yellowstone super eruption?

What is a supervolcano? The term “supervolcano” implies a volcanic center that has had an eruption of magnitude 8 on the Volcano Explosivity Index (VEI), meaning the measured deposits for that eruption is greater than 1,000 cubic kilometers (240 cubic miles).

How is the magnitude of a volcano measured?

The Volcanic Explosivity Index (see table below) is the volcanic equivalent to the Richter Scale. The VEI is used to identify the magnitude of a volcanic eruption. The VEI combines the magnitude and intensity into a single number of a scale of 0 (least explosive) to 8, the most explosive.

What is the most important factor used to determine the volcanic explosivity index of an eruption?

The primary eruption characteristic used to determine the volcanic explosivity index is the volume of pyroclastic material ejected by the volcano. Pyroclastic material includes volcanic ash, tephra, pyroclastic flows, and other types of ejecta.

What is the volcanic explosivity index vei of a Yellowstone super eruption?

How is the Volcanic Explosivity Index ( VEI ) used?

Measuring Explosive Eruptions. Chris Newhall of the United States Geological Survey and Stephen Self of the University of Hawaii developed the Volcanic Explosivity Index (VEI) in 1982. It is a relative scale that enables explosive volcanic eruptions to be compared with one another.

How is the volcanic explosivity index related to tephra?

Volcanic Explosivity Index: The volcanic explosivity index is based upon the volume of tephra produced during an eruption. The spheres in this diagram give a relative size comparison for each step of the index.

How is the explosivity of a volcano determined?

(Public domain.) Volume of products, eruption cloud height, and qualitative observations (using terms ranging from “gentle” to “mega-colossal”) are used to determine the explosivity value. The scale is open-ended with the largest volcanic eruptions in history (supereruptions) given magnitude 8.

What is the value of a volcanic eruption?

A value of 0 is given for non-explosive eruptions, defined as less than 10,000 m3 (350,000 cu ft) of tephra ejected; and 8 representing a mega-colossal explosive eruption that can eject 1.0?—1012 m3 (240 cubic miles) of tephra and have a cloud column height of over 20 km (12 mi).