Volcano Case Study: Calbuco

Question 1

Name my detailed volcano case study

Answer 1

Calbuco, Chile, April 2015

Question 2

What type of volcano is Calbuco?

Answer 2

Stratovolcano

Question 3

How high above sea level is Calbuco?

Answer 3

2,015m elevation

Question 4

Which region is Calbuco situated?

Answer 4

Los Lagosregion, Chile, South America

Question 5

Name the surrounding places around Calbuco

Answer 5

Llanquihue Lake = 11km north
Chapo Lake
Puerto Varas = 41,255 population
Puerto Montt = 176,000 population, 30km away

Question 6

What is the population of Puerto Varas?

Answer 6

41,255

Question 7

What is the population of Puerto Montt?

How far away is it from Calbuco?

Answer 7

176,000

30km

Question 8

When has Calbuco erupted in the past?

Answer 8

1961
1972
Many times before that

Question 9

When was Calbuco’s latest eruption?

Answer 9

22nd April 2015 at 18:04

Question 10

How far in advance did scientists detect warning signs of the eruption?

Answer 10

At 17:00, an hour before the eruption

Question 11

What warning signs did scientists detect that foreshadowed the eruption?

Answer 11

Volcanic earthquakes were detected an hour before the eruption

Question 12

How long did the eruption last?

Answer 12

90 minutes

Question 13

How many people were evacuated?

Answer 13

Everyone within a 20km radius was warned to evacuate.

5,000 people left.

Question 14

Did the eruption cause flight cancellations? If so where and why?

Answer 14

Yes, in Chile, Argentina, Uruguay due to ash plumes

Question 15

Why were people advised not to go within 200m of drainages?

Answer 15

Due to lahar hazards

Question 16

How far did pyroclastic flows travel?

Answer 16

On 23rd April they had travelled 7km

Question 17

How far did lahar travel?

Answer 17

On 23rd April they had traveled 15km

Question 18

What did ash fall cause?

Answer 18

Ash fall caused roads and bridges to be blocked

Question 19

How far was tephra ejected on the 23rd April? Where did the deposits fall?

Answer 19

5km, falling mostly to the N and NE

Question 20

How thick was the tephra when it fell?

Answer 20

Tens of cm in Los Lagos region.

A few mm in Los Rios and La Araucania regions.

Question 21

What did the weight of ash cause?

Answer 21

Some nearby houses collapsed

Question 22

What continued to happen up until 30th April?

Answer 22

Volcanic earthquakes continued.

Ash plumes rose even higher.

Question 23

How far did lava flow travel?

Answer 23

Lava reached and entered Chapo Lake

Question 24

Was anyone killed by the eruption?

Answer 24

No

Question 25

Why did Calbuco erupt?

Answer 25

It is situated on the boundaries of 3 tectonic plates: Nazca, S American, Antarctic. Nazca plate subducts under S American -> mid ocean ridge and trench. = pressure and seismic activity.

Question 26

What type of plate boundary is Calbuco found at?

Answer 26

Destructive boundary

Question 27

What concerns did the ash cause?

Answer 27

Respiratory illness eg silicosis. Building collapse. Failure of crop harvest.

Question 28

Give the social risks of volcanic areas

Answer 28

Ash settles -> respiratory illnesses, building collapse, crop failure. Flight delays / cancellations. Injury / death due to pyroclastic flows, lava flows, debris. People become trapped due to damaged bridges / roads. Height of Calbuco ash plume -> risk of water contamination -> limits drinking / agricultural water use.

Question 29

Give the economic risks of volcanic areas

Answer 29

Building damage due to ash, p. flows, lava, lahars. Building damage / injuries -> people can't work -> possible recession. Flight delays/cancellations due to ash. Water contamination -> need to import water.

Question 30

Give the environmental risks of volcanic areas

Answer 30

CO2 emissions -> global warming. Large ash plumes -> cool earth. Sulfur dioxide emissions -> acid rain. Water contamination -> instability of ecosystems -> species die.

Question 31

How did people respond to the eruption?

Answer 31

Officials put area on "red alert". Warned everyone within 20kmto evacuated safe houses in Puerto Montt. Farmers moved around 4000 sheep to protect livelihood. Airlines cancelled flights. Town on La Ensenada (14km away) were aided in clean up by 400 army personnel.