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Transcript of Volcano Project
An example of a complex volcano is Silverthrone in British Colombia, Canada. Volcanic cones are among the simplest volcanic formations. They are built by ejecta from a volcanic vent, piling up around the vent in the shape of a cone with a central crater. Volcanic cones are of different types, depending upon the nature and size of the fragments ejected during the eruption. A cinder cone is a steep hill of volcanic fragments that collect around and downwind from a volcanic vent. The rock fragments, often called cinders, are glassy and contain lots of gas bubbles "frozen" into place as magma exploded into the air and then cooled quickly. Cinder cones range in size from tens to hundreds of meters tall. Cinder cones are made of pyroclastic material.
An example of a ciner cone is Dragon Cone in British Colombia. A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their large size and low profile, resembling a warrior's shield. This is caused by the highly fluid lava they erupt, which travels farther than lava erupted from more explosive volcanoes. This results in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form. Shield volcanoes contain low viscosity magma making it have flowing mafic lava.
An example of a shield volcano is the chain of Hawaiian Islands. A stratovolcano, or composite volcano, is a tall, conical volcano built up by many layers of hardened lava, volcanic ash and other materials. Stratovolcanoes are characterized by a steep profile and explosive eruptions. The lava that flows from stratovolcanoes typically cools and hardens before spreading far due to the densety of the fluid.
An example of a stratovolcano is Mount Ngauruhoe in North Island, New Zealand. This particular volcano is active. Here is a map showing the location of active volcanoes. shown with a triangle This was the ongoing activity at Sakurajima, one of Japan's most active volcanoes. Sakurajima lies less than 10km from the large city of Kagoshima, and has a history of violent, explosive eruptions. It was in a constant eruptive state, with 3 or 4 explosions per day when the footage was taken in September 2011 Hazards and Damaging Effects Lava flows destroy everything in its path, and its route is completely random.
Pyroclastic flows are a mixture of volcanic gases, which are extremely hot and move very fast. Early warning for this hazard are virtually impossible and the only method of risk migration is evacuation before such eruptions from areas likely to be affected.
Ashfalls may not directly be dangerous to the life of humans, but the activity of collapsing roofs and houses are fairly common. Lots of damage may be caused for agriculture and industry even at distances up to tens of kilometres from a vent.
Poisonous gases can be shot out during an eruption of a volcano which can be hazards to lives. These gases can sometimes be ejected without there being an eruption. These gases cause mass fatalities if inhaled.
Lahars are a common major hazard for humans and property. They possess great destructive power and are volcanic mud and debris flows. They can develop as a consequence of an eruption. The majority of the time the volume and force of the lahars is is so great that it is uncontrolable
d Mount Nyiragongo Case Study Basic Facts Mount Nyiragongo is a stratovolcano in the Virunga Mountains. It is located inside Virunga National Park, in the Democratic Republic of the Congo, about 20 km north of the town of Goma and Lake Kivu and just west of the border with Rwanda. The main crater is about two km wide and usually contains a lava lake. The crater presently has two distinct cooled lava benches within the crater walls. Mount Nyiragongo City of Goma Goma is a city in the eastern Democratic Republic of the Congo, on the northern shore of Lake Kivu, next to the Rwandan city of Gisenyi. The lake and the two cities are in the Albertine Rift, the western branch of the East African Rift system. Goma lies only 13 to 18 km due south of the crater of the active Nyiragongo Volcano. Volcanism at Nyiragongo is caused by the rifting of the Earth's crust where two parts of the African Plate are breaking apart. A hot spot is probably also partly responsible for the great activity at Nyiragongo and Nyamuragira. Effects Mount Nyiragongo is set along the East African Rift zone, a 6000 mile crack in the earth's crust. This zone marks a triple junction where three plates (the Arabian Plate and the two parts of the African Plate (Nubian and Somalian) are moving away from each other at what is a constructive plate boundary. As the plates move apart molten rock is forced up in volcanic eruptions. Nyiragongo volcano erupted on Thursday 17th January 2002, sending plumes of ash into the atmosphere and sending three rivers of volcanic lava flowing down its sides. The eruption has been hailed as the worst in central Africa for 25 years. Following Thursday's eruption, hundreds of thousands of people were evacuated from their homes, fleeing for their lives. Almost half of the town of Goma which is 11 miles south of the summit was reported to be ablaze as rivers of lava up to 6 feet deep and 30 metres wide swept through it. The town is situated on the shores of Lake Kivu and as lava flows into the lake, scientists warned of possible further dangers resulting from possible reactions between lava and gases in the lake.
An estimated 45 people were killed in the first 24 hours and was estimated at around 500 deaths. There are also hundreds of injuries including burn victims and victims of smoke inhalation.
The air is thick with the smell of sulphur.
At least 14 villages have been destroyed as lava swept down the sides of the volcano.
British aid workers are travelling to the country to offer help to victims of the volcanic eruption.(RESPONSE)
Goma has been inundated by lava with estimates of up to 80% of buildings destroyed or burning, including government buildings, schools and hospitals
Hundreds of thousands of refugees required shelter as their homes have been destroyed.
As well as lacking shelter, many refugees were without food or water since the eruption commenced and there is no electricity or running water supplies in the town of Goma.
As people fled the town of Goma, looting began from shops in the deserted streets.
Communications have been destroyed. The town's airport is unusable as lava spread across the runway and the main road north to Uganda was completely inaccessible.
Goma's port was also been destroyed. By Cameron Sandiford 9T This picture shows the Nyiragongo volcano and the East African Rift Zone As aid responses go, Goma was not badly served. Many UN and NGO bodies, though often themselves affected by the destruction (UNICEF lost a warehouse full of medicines and school supplies worth $700,000), were already in place in Goma, and several new agencies came in to help. After a few days, a system of joint UN and NGO coordination ‘commissions’ was well in place, notably for health, education and child protection, and food and non-food aid.
Surprisingly, the need for shelter was not as bad as feared, as most of the 80,000 displaced people moved in with relatives for the first few days. For this major and crucial need, only cash would do. Houses for rent were available, and those who had money rented rooms and space towards the west of the town. A significant population did find it difficult and temporary camps grew up in some of the untouched schools and church compounds, which later had to be evacuated as a major effort was made to restart education.
There was no immediate danger of starvation. Goma is well supplied with food, which is normally quite cheap; the problem was the money to buy it with. The town is a busy commercial centre, a hive of economic activity and the main point of entry for goods from the outside world for much of eastern Congo. Markets quickly reopened after the eruption, and supplies of vegetables and fruit were soon re-established.