Volcano Case Study: Calbuco Flashcards
Name my detailed volcano case study
Calbuco, Chile, April 2015
What type of volcano is Calbuco?
Stratovolcano
How high above sea level is Calbuco?
2,015m elevation
Which region is Calbuco situated?
Los Lagosregion, Chile, South America
Name the surrounding places around Calbuco
Llanquihue Lake = 11km north
Chapo Lake
Puerto Varas = 41,255 population
Puerto Montt = 176,000 population, 30km away
What is the population of Puerto Varas?
41,255
What is the population of Puerto Montt?
How far away is it from Calbuco?
176,000
30km
When has Calbuco erupted in the past?
1961
1972
Many times before that
When was Calbuco’s latest eruption?
22nd April 2015 at 18:04
How far in advance did scientists detect warning signs of the eruption?
At 17:00, an hour before the eruption
What warning signs did scientists detect that foreshadowed the eruption?
Volcanic earthquakes were detected an hour before the eruption
How long did the eruption last?
90 minutes
How many people were evacuated?
Everyone within a 20km radius was warned to evacuate.
5,000 people left.
Did the eruption cause flight cancellations? If so where and why?
Yes, in Chile, Argentina, Uruguay due to ash plumes
Why were people advised not to go within 200m of drainages?
Due to lahar hazards
How far did pyroclastic flows travel?
On 23rd April they had travelled 7km
How far did lahar travel?
On 23rd April they had traveled 15km
What did ash fall cause?
Ash fall caused roads and bridges to be blocked
How far was tephra ejected on the 23rd April? Where did the deposits fall?
5km, falling mostly to the N and NE
How thick was the tephra when it fell?
Tens of cm in Los Lagos region.
A few mm in Los Rios and La Araucania regions.
What did the weight of ash cause?
Some nearby houses collapsed
What continued to happen up until 30th April?
Volcanic earthquakes continued.
Ash plumes rose even higher.
How far did lava flow travel?
Lava reached and entered Chapo Lake
Was anyone killed by the eruption?
No
Why did Calbuco erupt?
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.
What type of plate boundary is Calbuco found at?
Destructive boundary
What concerns did the ash cause?
Respiratory illness eg silicosis.
Building collapse.
Failure of crop harvest.
Give the social risks of volcanic areas
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.
Give the economic risks of volcanic areas
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.
Give the environmental risks of volcanic areas
CO2 emissions -> global warming.
Large ash plumes -> cool earth.
Sulfur dioxide emissions -> acid rain.
Water contamination -> instability of ecosystems -> species die.
How did people respond to the eruption?
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.
