Humanities Assessment
By Ziteng Huang (Sonny) 10KNI
Mount Mayon
Mount Mayon is an active volcano in the province of Albay in Bicol Region of the Philippines and it is also one of the most active Stratovolcanoes on Earth. It erupted 50 times in the past 400 years, those eruptions had briefly killed 1335 people and effect over millions of residents. the earliest eruption was recorded in 1616 and the biggest eruption was recorded in January the 1st of 1814. This eruption killed over 1200 people instantly and bury the whole Kagarshawi Town but still, Mt Mayon has the most perfect symmetry conical shape in all volcanoes around the world. The shape is resulted by the volcanic ashes and lava by stacking layers.
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Task One:
The Natural processes that produced your chosen eruption
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Why would the volcanic eruption happen?
Mount Mayon is located on the special zone called ‘the ring of fire’, which is a zone that has volcanic eruptions and earthquakes frequently. The ring of fire is 40000 kilometers long. It contains 75 percent of the volcano all around the world and 90 percent of the earthquake as well. Over 81 percent of the most catastrophic earthquakes happened on the ring of fire.
A volcanic eruption is the most common way which Earth used to release its pressure from the mantle. The mantle is made by semi-molten rocks which were molten by the extreme heat from the core, so there will be lots heat to be released and then they have to be released otherwise the crust would be molten as well. The heat from the core would cause the convection current which is the molten rock moving away from the heater core to the Earth’s surface and cooling down then moving back to the core as fluid magma again. The convection current would eventually pull different plates on the surface of the Earth away from each other, make them collide to others and slide across each other. There are four different situations that the different plates could be affected and they are:
- Constructive boundary
- Collision boundary
- Destructive boundary
- Conservative boundary
That activity could cause different kinds of other natural disasters such as earthquake and tsunami and another thing is the oceanic crust is usually denser than continental crusts so the oceanic crust often went under the continental crust to form a destructive boundary. Mt Mayon is a distinct example.
The process of Mt Mayon volcanic eruption.
The first process that causes the Mount Mayon to erupt is the destructive boundary between the Philippine Sea plate and the Eurasian plate. The Philippine Sea plate is going under the Eurasian plate. The magma melts the plates around it which makes lots of extra magma, gas, and heat. As the record from the Xinhuashe publisher a few weeks before the eruption, Mt Mayon had two small gas eruptions on the 27th of the December in 2018. Two volcanic ash columns are 200 meters and 600 meters. Just 24 hours before the gas eruption, the volcano scientist had recorded the volcanic earthquake and the light emission once. This means the magma has likely reached the surface of the Earth.
The second process that causes Mount Mayon to erupt is the pressure built up. As I said in the first process, there are lots of extra magma, gas and heat have been trapped under the crust so the pressure will be trapped under the crust. Due to the monitoring data, the Mt Mayon had the mountainside protrude since the 25th of June in 2018, this means the underground structure has been eroded by the magma underneath and the pressure is also almost reached the critical point. At this stage, the magma now has already reached the surface of the Earth.
The third process that causes the Mount Mayon to erupt is because the magma now has reached the surface of the Earth, which is the top or the side of the volcano crater or the ridge. Magma brings a huge amount of heat energy and eventually the heat energy will cause the lava in the mountain heat up too. Once the lava gets too hot, it melts a hole in the top of the mountain and even further, the lava melts the rocks around it and a lot more pressure under the crust apparently built up again.
The fourth process that causes Mount Mayon to erupt is when the balance between the pressure and the thickness of the lava become unbalanced, the pressure suddenly released. The volcano usually erupts by shooting lava into the air or overflow the lava out of the crater and flowing down the volcano. Sometime the eruption could be explosive. For example at 02/02/1993 13:15, the Mayon volcano violently erupted again. The volcanic ash has a maximum height of 4500 meters, and the outbreak killed 75 people. The reason why the eruption is explosive is that the thickness of the lava was very big so it allows more pressure to be held under the crust in order to create a lot more violent eruption.
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Task Two:
The effect of the eruption on the natural and cultural environment.
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The effects on the environment
The eruption by Mt Mayon has caused several effects on the environment in the local city and even around the world. There are several positive and negative affections that Mt Mayon did to the environment.
Positive affections：
-Firstly, after the volcanic lava cools down, it increases a huge amount of new land area. These land areas will eventually become forests, which means it also increases the vegetation areas and the population of animals, insects as well as more accessibility to the human development zone. For example, Hawaii.
-Secondly, the volcanic ash is incredibly rich in nutrition. It means the land which once mixed with volcanic ashes will be extremely fit for agriculture. The grain production would eventually increase because of the volcanic ashes.
Negative affections:
-Firstly, the volcanic ash is very heavy. When the volcano erupts, for example, Mt Mayon, the volcanic ash would stack above the roof. This will likely break the house or make them collapse which could cause economic losses
Secondly, a huge volcanic eruption could cause the global temperature drops or the local temperature drops rapidly because the huge amount of carbon dioxide was produced. For instance the Mt Mayon and Pinatubo. The global temperature drop could lead to global species extinction.
The effects on culture
Positive affections:
-Firstly, the volcano could be related to the gods. This happened a long time ago even before the agricultural revolution. The clothes, the buildings, and the custom could be all related to the volcano.
Negative affections:
The volcanic eruption will eventually wipe the whole village or city off sometime. The catastrophic events often happen at Mt Mayon. It erupted 50 times in the past 400 years, those eruptions had briefly killed 1335 people and effect over millions of residents. the earliest eruption was recorded in 1616 and the biggest eruption was recorded in January the 1st of 1814. This eruption killed over 1200 people instantly and bury the whole Kagarshawi Town.
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Task three:
How people prepare for and responded to the eruption
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Usually, before the eruption of Mt Mayon, the Philippine government will evacuate all the residents in the city. For example on August 7th of 2006, the volcano scientist detected 21 low-frequency volcanic earthquakes in a day. This makes the Philippine government worried about the eruption of the Mt Mayon so they forced about 20000 residents to perform emergency evacuation and to be sent to the refugee camp because the volcanic ash could damage human’s lungs and the lahar, lava is dangerous as well. The local flights would also be canceled because the volcanic ash could block the engine inlet of the aircraft which can cause disasters. Sometimes human could prevent the gas eruption by using pipes to release the pressure underneath the volcano.After the Mt Mayon erupted, the Philippine government will give emergency assistance to the residents who have been affected.
After the eruption of the Mount Mayon, the Philippines volcano scientist working together with the Provincial Disaster Risk Reduction Management Council to ensure local safety. Then they measure the depth of the volcanic ashes and then analyze the possible solutions for the eruption. Most of the time they will save the animals that were burnt during the eruption and other human properties that damaged during the eruption.
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