Wellington, New Zealand Plate Tectonics
Region Map of Wellington, New Zealand.
Disaster Preparedness Several different disasters are possible of occurring in Wellington. Things such as volcanoes, tsunamis, earthquakes, landslides, storms, and floods, are possible to occur at any moment. There are different preparedness plans for each.
Earthquakes In the event of an earthquake, you would have to practice the process of “Drop, Cover, and Hold.” Which is shown here:
This is a diagram of what you would do if you were indoors during this situation. You are supposed to stay indoors until the shaking stops and you are sure that it is safe to exit.
What Causes Earthquakes Earth’s outermost layer is made of huge, slow moving blocks of rock known as tectonic plates. Most earthquakes happen where two tectonic plates meet. Stress builds up in
the plate’s crust, and it suddenly breaks, releasing a large amount of energy. This usually happens along a “fault line.” New Zealand has earthquakes because it lies on a boundary between the Australian and Pacific plate. Along the plates are several faults, such as the Alpine Fault and the Wellington Fault. Blocks of rock on the faults sometimes move upwards or sideways, which cause earthquakes. Every year, the country has thousands of earthquakes. About 200 of them are big enough to be felt. Since 1840, nearly 300 people have died during large earthquakes in New Zealand.
Making Towns And Cities Safer In 1931, a magnitude 7.8 earthquake struck Napier and Hastings. During this earthquake, 256 people died. Many of the deaths were caused by falling buildings crushing the person(s). Others died in fires that could not be stopped due to city water pipes bursting. Since then, strict rules about design and construction mean that new buildings and bridges should not collapse during a major earthquake. Older buildings have been strengthened.
Landslides
Landslides can be caused by many different things. Such as: •
Weak rock and steep slopes.
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Removing trees or bush. (Deforestation)
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Roadworks on hillsides
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A heavy rainstorm.
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A large earthquake.
There are different types of landslides. Some bring down a mountainside, and travel at 200 kilometers an hour. Others are shallow or slow, moving only a few centimeters a year. Landslides move in different ways, such as falling, sliding sideways, or flowing.
Landslides occur in many different locations. In the Southern Alps and other mountains, rocks can slide, sometimes in a huge avalanche. 12 million cubic meters of Aoraki/Mt Cook fell away in 1991, lowering the peak by at least 10 meters. Some flatter land has layers like a custard square. The harder “crust” on top crushes the softer “custard” underneath, making the top layer fall down. This happened in 1979 at Abbotsford, Dunedin, when 69 houses collapsed.
Major Landslides These are a couple of major landslides since the 1840s, 362 people have died in landslides. The landslides are as follows:
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Waihī, Lake Taupō, 1846: After heavy rain, a mud flow smothered 55 people at a Māori village.
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Murchison, 1929: A major earthquake caused landslides that killed 14 people and blocked the roads for months.
Protecting People Laws about buildings, roads, and farming have been made, which reduce the risk of landslides where people are living. Orange and yellow road signs warn motorists to be careful.
Tsunamis
Because of New Zealands long, exposed cost line, it’s vulnerable to destructive waves that periodically surge onto it’s shores. Since the catastrophic Indian Ocean tsunami in 2004, there has been a sharpened awareness of the dangers. Tsunamis can occur in any ocean, but most occur in the Pacific, triggered by the earthquakes and volcanoes there. Tsunamis over a meter high reach New Zealand about 12 times a day.
New Zealand Tsunamis •
In the 15th century, tsunamis may have forced many Māori to move inland from the coast. A massive wave wiped out an entire village on D’Urville Island.
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In 1855, after a powerful earthquake, water in Wellington Harbour spilled on to Lambton Quay as the land moved and the harbour tilted. Large tsunami waves also rushed in from Cook Strait, at times leaving ships grounded on the harbour bottom.
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A local earthquake at Gisborne in 1947 caused a tsunami 30 minutes later. One man said the wall of water roared like an express train. A 10-metre wave smashed a cottage, but no-one was killed.
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In 1960 a powerful earthquake caused a tsunami that killed thousands of people in Chile and across the Pacific. On 23 May, boats, houses, and animals were lost as waves hit New Zealand's east coast.
Volcanoes
The NZ region lies within the Pacific Ring of Fire. Due to that, volcanic eruptions occur regularly, especially from White Island, Ngauruhoe and Ruapehu. All the potentially active volcanoes are monitored to give warning of an impending eruption. An active volcano shows signs of unrest (For example, earthquakes, etc.), or is currently erupting. Whakaari, (White Island,) discharges steam almost continuously and ash every few years. A dormant (not currently erupting) volcano is expected to erupt again. Such as Taranaki (Mt. Egmont.) An extinct volcano has shut off and will not erupt again. For example, Dunedin volcano, which has erupted 11 million years ago. There are different types of volcanoes. A more familiar volcano is known as “the coneshaped mountain� with ash coming from the top. But some of the most explosive volcanoes are very large craters, known as calderas, which are often filled with water. New Zealand has three main types of volcanoes, which are each associated with different types of magma. Cone volcanoes, such as Ruapehu and Taranki (Mt. Egmont), formed from many eruptions over thousands of years. The magma type is called
Andesite. Caledras such as Lake Taupo. A major eruption of ash and pumice can form a hole 10-25 kilometers in diameter. The magma type is Rhyolite. Volcanic fields as in Auckland and Northland. Over thousands of years, there are small eruptions in the area. Each time this happens, a new volcano forms, but it normally doesn’t erupt gain. The magma type is Basalt.
Preparation for these events Stopbanks have been built along rivers that often flood, so that when the water is high it stays in the river channel. Buildings, bridges, and overpasses are designed so that they won’t collapse when there is an earthquake or storm-force winds. People are not allowed to build over active fault lines or where landslides are likely. Services give warnings of sever weather, eruptions (volcanoes,) landslides, and tsunamis. The regions of the country handle their own emergencies, they try to reduce the possible damage from natural hazards and train people what to do in an emergency. Where there is a disaster, they save lives and property, and rebuild the community.
Economic Graph of Wellington