1. And other Plinian Eruptions
Vesuvius
And other Plinian Eruptions

2. •Largest kind of eruption •Also known as “Vesuvian eruptions”
 Plinian Eruptions 
•Largest kind of eruption
•Also known as “Vesuvian eruptions”
•Ash has been known to been pushed about 28 miles into the sky
•Named after Pliny the Younger

3. How to identify a Plinian Eruption
•Plinian eruptions send columns of ash and gas high into the stratosphere
•The eruption can last from days to months
•Ejects large amount of pumice
•Continuous powerful gas blast eruptions

4. Mount Vesuvius's Plinian Eruptions
Mount Vesuvius's Plinian Eruptions
Vesuvius Notes
Background:
·        Mount Vesuvius is located in Italy east of the city Naples
·        It is on the coast of the Bay of Naples
·        It is most famous for its AD 79 eruption that killed 10,000-25,000 people
·        In the world, it is the most densely populated volcanic region
·        It is regarded as extremely dangerous, and often has plinian (explosive) eruptions
·        Formed by the collision of the African and the Eurasian plates
·        Has had many eruptions, that vary greatly in severity
·        Before AD 79, it had several eruptions of decent size
Eruption of AD 79:
·        Lasted 19 hours
·        Produced white ash
·        Erupted about 1 cubic mile of rock and ash
·        Had several foreshocks before the actual eruption, so Pompeii and neighboring towns may not have fully recovered
·        The Romans grew accustomed to these small tremors, so they were not fully ready to believe it was the real thing when it actually erupted
·        Had to phases: The Plinian eruption, and then the pyroclastic flow
·        Had Pliny the Younger write the only reliable eyewitness account, thus the name of a Plinian eruption
·        Only three nobles known by name died: Pliny the Elder, Agrippa, and his wife
·        38% of Pompeii victims were in the ash fall deposits
·        The other 62% were killed by pyroclastic surge deposits
Vesuvius continued to erupt many times after, and currently lies dormant today.

5. Background Located in Italy on the coast of the Bay of Naples
 It is the most densely populated volcanic region in the world
 It was formed by the collision of the African and Eurasian Tectonic Plates
 It has had several eruptions that vary greatly in severity

6. Leading Up to the Eruption of 79 AD
A powerful earthquake happened 17 years before AD 79
Some of the damage from the earthquake had not been rebuilt when the eruption came
Additionally, a small earthquake occured in 64 AD
 On August 20, AD 79, small earthquakes started occuring
The Romans grew used to the mild tremors near Vesuvius 
Vesuvius Notes
Background:
·        Mount Vesuvius is located in Italy east of the city Naples
·        It is on the coast of the Bay of Naples
·        It is most famous for its AD 79 eruption that killed 10,000-25,000 people
·        In the world, it is the most densely populated volcanic region
·        It is regarded as extremely dangerous, and often has plinian (explosive) eruptions
·        Formed by the collision of the African and the Eurasian plates
·        Has had many eruptions, that vary greatly in severity
·        Before AD 79, it had several eruptions of decent size
Eruption of AD 79:
·        Lasted 19 hours
·        Produced white ash
·        Erupted about 1 cubic mile of rock and ash
·        Had several foreshocks before the actual eruption, so Pompeii and neighboring towns may not have fully recovered
·        The Romans grew accustomed to these small tremors, so they were not fully ready to believe it was the real thing when it actually erupted
·        Had to phases: The Plinian eruption, and then the pyroclastic flow
·        Had Pliny the Younger write the only reliable eyewitness account, thus the name of a Plinian eruption
·        Only three nobles known by name died: Pliny the Elder, Agrippa, and his wife
·        38% of Pompeii victims were in the ash fall deposits
·        The other 62% were killed by pyroclastic surge deposits
Vesuvius continued to erupt many times after, and currently lies dormant today.

7. Eruption of 79 AD Produced white ash
 Had two phases, the plinian eruption, and the pyroclastic flow
 Erupted on August 24th and 25th
People did not react immediately because they were used to mild tremors 
Vesuvius Notes
Background:
·        Mount Vesuvius is located in Italy east of the city Naples
·        It is on the coast of the Bay of Naples
·        It is most famous for its AD 79 eruption that killed 10,000-25,000 people
·        In the world, it is the most densely populated volcanic region
·        It is regarded as extremely dangerous, and often has plinian (explosive) eruptions
·        Formed by the collision of the African and the Eurasian plates
·        Has had many eruptions, that vary greatly in severity
·        Before AD 79, it had several eruptions of decent size
Eruption of AD 79:
·        Lasted 19 hours
·        Produced white ash
·        Erupted about 1 cubic mile of rock and ash
·        Had several foreshocks before the actual eruption, so Pompeii and neighboring towns may not have fully recovered
·        The Romans grew accustomed to these small tremors, so they were not fully ready to believe it was the real thing when it actually erupted
·        Had to phases: The Plinian eruption, and then the pyroclastic flow
·        Had Pliny the Younger write the only reliable eyewitness account, thus the name of a Plinian eruption
·        Only three nobles known by name died: Pliny the Elder, Agrippa, and his wife
·        38% of Pompeii victims were in the ash fall deposits
·        The other 62% were killed by pyroclastic surge deposits
Vesuvius continued to erupt many times after, and currently lies dormant today.

8. 38% of the victims were found in the ash fall deposits
Aftermath
10,000-25,000 people died
38% of the victims were found in the ash fall deposits
62% if the victims were killed by pyroclastic surge deposits
Erupted about 1 cubic mile of rock and ash
Lasted 19 hours
Vesuvius Notes
Background:
·        Mount Vesuvius is located in Italy east of the city Naples
·        It is on the coast of the Bay of Naples
·        It is most famous for its AD 79 eruption that killed 10,000-25,000 people
·        In the world, it is the most densely populated volcanic region
·        It is regarded as extremely dangerous, and often has plinian (explosive) eruptions
·        Formed by the collision of the African and the Eurasian plates
·        Has had many eruptions, that vary greatly in severity
·        Before AD 79, it had several eruptions of decent size
Eruption of AD 79:
·        Lasted 19 hours
·        Produced white ash
·        Erupted about 1 cubic mile of rock and ash
·        Had several foreshocks before the actual eruption, so Pompeii and neighboring towns may not have fully recovered
·        The Romans grew accustomed to these small tremors, so they were not fully ready to believe it was the real thing when it actually erupted
·        Had to phases: The Plinian eruption, and then the pyroclastic flow
·        Had Pliny the Younger write the only reliable eyewitness account, thus the name of a Plinian eruption
·        Only three nobles known by name died: Pliny the Elder, Agrippa, and his wife
·        38% of Pompeii victims were in the ash fall deposits
·        The other 62% were killed by pyroclastic surge deposits
Vesuvius continued to erupt many times after, and currently lies dormant today.

9. Eruptions after 79 AD
Had severe eruptions in 512
Other eruptions were noted in 787, 968, 991, 999, 1007, 1036
Had an extremely destructive eruption in 1631
Almost continuous eruptions continued after that until 1944

10. Mount Pinatubo Mount Pinatubo · An active volcano · Erupted in 1991
·                   An active volcano
·                   Erupted in 1991
·                   2nd largest eruption of 20th century
·                   Volcanic Explosivity Index (VEI) of 6
·                   Eruption was predicted; tens of thousands were evacuated from the area
·                   produced pyroclastic flows, ash deposits, and later lahars
·                   Ejected 10 billion metric tons of magma
·                   aerosols went into the stratosphere; formed a thin layer of sulfuric acid
§         Caused global temperatures to decrease 0.5°C (0.9°F)
Location
·                   Zambales Mountain Range, Philippines
·                   500,000 people continue to live within 40 km of the mountain
Eruption
·                   A succession of earthquakes were felt on March 15, 1991
·                   They continued for two weeks
·                   Experts concluded that volcanic activity was occurring
·                   On April 2, the volcano erupted with a series of small phreatic eruptions that continued for weeks
·                   Surrounding areas were covered with light layers of ash
·                   The first Magmatic eruption was June 3rd
·                   The first explosive eruption was on June 7th
§         It ejected an ash column 7km into the air
·                   After April 2nd eruption, the area surrounding was evacuated
·                   60,000 people got out
§         Was evaluated as a level 5 evacuation (very important)
·                   A more violent stage began on June 12th
·                   AN eruption column reached 19km at 3a.m.
·                   Pyroclastic flows reached as far as 4km from the volcano
·                   Another eruption 14 hours later produced a column 24 km high
·                   June 13th brought another 24km high eruption
·                   June 14th had a 21 km high eruption
·                   One final eruption occurred on the same day as Typhoon Yunya
§         34 km in the air and lasted 3 hours
§         Pyroclastic flows reached 16 km away
§         Rain mixed with the ash to produce lahars
·        A type of landslide
·                   After it was over 10 cubic kilometers of material was ejected
·                   10 times larger than the eruption in 1980 of Mt. Saint Helens
·                   800 people died
·                    

11. Background Information
Located in the Philippines
The Tri-Cabusilan Mountain range
The island of Luzon
5,840 ft (1,780 m) high
Formed when Philippine Mobile Belt slid over Eurasian plate
500,000 people are still living within 40km
It has been over 450 years since the previous one
Located in Phillipines
Tri-Cabusilan Mountain range
Luzon Island
5840 ft tall
Taller than Vesuvius, shorter than Mt. St. Helens
The Phillipine Mobile plate slid over Eurasian plate
500,000 people are living within striking distance
The volcano is still active
Natives in the area don't have knowledge about the volcano
Before 1991 eruption, it had been over 450 years
Another big eruption will come according to experts 

12. Leading Up to the Eruption
7.7 Earthquake occurred 100 km northeast on July 16,1990
A succession of earthquakes were felt on March 15, 1991
Experts decided that volcanic activity was occurring
 60,000 people were evacuated
Small phreatic eruptions started on April 2 
7.7 earthquake preceded eruption by one year
 Seismic activity was happening in the volcano
·                   A succession of earthquakes were felt on March 15, 1991
·                   They continued for two weeks
·                   Experts concluded that volcanic activity was occurring
At least 60,000 people were evacuated
§         Was evaluated as a level 5 evacuation (very important)
Most likely more
·                   On April 2, the volcano erupted with a series of small phreatic eruptions that continued for weeks
·                   Surrounding areas were covered with light layers of ash

13. The Eruption Magma first erupted on June 3rd
The first explosive eruption was June 7th
This forced ash 7km into the air
A second eruption on June 12th had ash column 19km high
Later that day an eruption had an ash column 24km high
            The first Magmatic eruption was June 3rd
·                   The first explosive eruption was on June 7th
§         It ejected an ash column 7km into the air 
·                   A more violent stage began on June 12th
·                   AN eruption column reached 19km at 3a.m.
·                   Pyroclastic flows reached as far as 4km from the volcano
·                   Another eruption 14 hours later produced a column 24 km high
·                   June 13th brought another 24km high eruption
·                   June 14th had a 21 km high eruption

14. The Climatic Eruption On June 14th the largest eruption hit
The ash column went 34km into the air
Typhoon Yunya hit the Philippines the same day
Rain caused many lahars, or mudslides that destroyed surrounding forests
Throughout all eruptions, pyroclastic flows reached as far as 16 km away
·                   One final eruption occurred on the same day as Typhoon Yunya
June 14th
§         34 km in the air and lasted 3 hours
§        
§         Rain mixed with the ash to produce lahars
Pyroclastic flows reached 16 km away

15. Aftermath All in all, Mt. Pinatubo ejected 10 cubic km of material
This is 10 times larger than Mt. St. Helens
800 people died
would have been more without evacuation
VEI rating of 6; Mt. St. Helens was rated 5
(Volcanic Explosivity Index)
nd largest eruption of the 20th century
Mt. Pinatubo ejected 10 cubic km of material
10 times larger than Mt. St. Helens
It produced 1 cubic km
800 people died
57 died in Mt. St. Helens
Thousands died in Vesuvius' eruption
They were unaware of the volcano
VEI rating of 6, Mt. St. Helens was 5
Vesuvius couldn't be measured
Mt. Pinatubo was the second largest volcanic eruption of 20th century
Largest was the 1912 eruption of  Novarupta

16. Mt. St. Helens

17. Mount St. Helens -8,365 feet (2550 m)
-Location: Skamania County, Washington, USA
-Mount St. Helens most famous eruption was on May 18, 1980 at 8:32 am, which was the deadliest and most economically destructive volcanic event in the history of the U.S.

18. 1980 Eruption
-Mount St. Helens experienced a 4.2 magnitude earthquake on the 20th of March, and steam started venting seven days later.
-The mountain stated to bulge about four weeks later and on May 19th, a 5.1 magnitude earthquake started a massive collapse of the north side of the mountain.
-It then released the largest amount of debris ever recorded.
-Over 1.5 million metric tons of sulfur dioxide was released into the air.
-Volcanic mudflows destroyed bridges and lumber camps, and a total of 3,900,000 cubic yards of material was transported 17 miles south.
-Ash traveled up to 16 miles above sea level; the ash reaching Idaho by noon and even collected on cars and roof as far as Edmonton in Alberta, Canada.

19. Aftermath -fifty seven people were killed
-two hundred fifty homes, forty seven bridges, fifteen miles of railways and one hundred eighty five miles of highway were destroyed. 
-The eruption caused a massive debris avalanche, reducing the elevation of the mountain's summit from 9,677 feet to 8,365 feet and replacing it with a one mile wide horseshoe-shaped crater.

20. Similarities All three volcanoes have erupted in the last century
Evacuation plans
Mt. Pinatubo and Mt. St. Helens evacuated
This saved many lives
Citizens of Pompeii were ignorant
Many died who could have been saved
 All are still active today
Another large eruption is bound to occur
Hopefully, the world will be ready and evacuated
Mt. St. Helens

21. Differences
Different amounts of people were killed in all three eruptions:
Vesuvius killed 10, people
Mt. St. Helens eruption, 57 people died
Mt. Pinotubo eruption, 800 people died
The Heights are different
Mt. Vesuvius is 4,203 ft
Mt. Pinatubo is 5,840 ft
Mt. St. Helens is 8,364 ft

22. Bibliography
geography.about.com/od/globalproblemsandissues/a/pinatubo.htm
expo.edu.ph/pinatubo/