Summer Test Questions That I Missed Flashcards
What are the 3 layers of the earth called
Crust,Mantle,Core
What us the crust?
The crust is tone outer layer. It is made of sold rock and the oceans and continents lie on top of the crust.
What is the mantle?
The mantle lies in the crust. It is made of molten rock called magma.
What is the core?
The core is the centre of the Earth. It is made of iron and nickel. It is the hottest part of the earth at 6000 degrees Celsius. The core can be divided into the inner core and the outer core.
What are plates?
The earths crust is broken into pieces called plates. The plates with land on top of them are called continental plates and the plates with oceans on top are called oceanic plates. The line where two plates meet is called a plate boundary.
What is a convection current and how is one formed?
When magma is heated in the mantle it rises towards the crust. As it rises it cools and moves sideways. This causes friction between the magma and the crust and pulls the plates. The magma cools and sinks back down into the mantle. This process is constantly repeated.
What is plate tectonics?
The study of plates and their movement is called plate tectonics. Pangea then broke up and the continents moved to the position they are today. Wegner called this continental drift.
What happens when plates collide?
Plates that collide with each other have destructive or convergent boundaries. Here the crust is destroyed. Huge pressure is built up and the heavier plate is pushed under the lighter plate. This is called subduction. The heavier plate melts back into the mantle. The lighter plate is lifted up forming fold mountains. Plates that collide also cause earthquakes and volcanos. Eg. The Andes are fold mountains
What happens when plates separate from each other?
Plates that separate from each other have constructive boundaries. Where new crust is created. Plates that separate from volcanic mountains,volcanic islands and mid-ocean ridges. Eg. Iceland is a volcanic island
What happens when plates slide past each other?
Plates that slide past each other have passive boundaries. Crust is neither created nor destroyed here. These plates are locked together and then release a Hugh amount of energy when they slide past each other. Sliding plates cause earthquakes and fault lines. Eg. The San Andres Fault is a fault line in California.
Where does most volcanic activity?
Most volcanic activity happens around the edge of the pacific plate. Which is why that area is known as the Pacific Ring of Fire.
What is a mid-ocean ridge
Eg. In the middle of the Atlantic Ocean, the American plates are separating from the Eurasian and African plates and the magma that rises up through the cracks or fissures there is crating a chain of mountains on the seabed known as the Mid-Atlantic Ridge
What is a volcanic island?
Mountains on the seabed,formed when magma wells up through the cracks into the crust. Sometimes it rises above the surface of the ocean. These mountains are called volcanic islands. Eg. Iceland
Describe the actions and lá led diagram on what happens in a volcano?
Magma can also rise hi from the magma chamber in the earths crust through the vent. A vent is a narrow tube in the crust. When magma reaches the surface we call it lava. Lava hot ash and rocks are thrown into the air as the volcano erupts and an ash cloud is formed. There is a build up of material around the vent. As more eruptions occur layer after layer is added to the volcano until a cone shaped mountain is formed. The lava counties to flow from the crater to the top of the volcano. An example of a volcano would be Mount St Helens USA
Name 3 types of volcanoes
Active volcano
Dormant Volcano
Extinct volcano
What is an active volcano
Active volcanos erupt regularly. Eg. Mount Vesuvius in Italy
What is a dormant volcano
Dormant volcanoes have not erupted for a long time, but might erupt again. Eg. Mount Vesuvius in Italy
What is a extinct volcano
An extinct volcano will not erupt again. Eg. Croghan Hill Co.Offaly
What are 3 positive socio-economic effects of volcanoes?
- The soils made from lava are rich in minerals and so are very suitable for agriculture
- Tourist visit sites of some famous volcanos such as Mount Etna in Sicily Italy.
- Water heated underground by volcanic activity can be used to generate geothermal energy to heat people’s homes
What are 3 negative socio-ecomic effects of volcanoes
- Gases provided by volcanoes such as sulphur dioxide,can poison people who live nearby and cause acid rain. This can affect activities such as agriculture,fishing and farming.
- A lava flow burns everything in its path. There can be huge loss of human life when a volcano erupts.
- When volcanic material mixes with water from rivers or rain or melting snow and ice a river of mud called a lahar can be created
What is geothermal energy?
Geothermal energy is energy produced from the heat of the Earth This type of energy production is a major positive effect of volcanic activity in Iceland.
Name 3 ways geothermal energy is used in Iceland
• The steam from the hot water is used to create electricity, which provides power for factories, offices and houses.
• Water heated by geothermal energy is piped into offices, schools and people’s homes and used to heat them
• It is one of the cheapest and most sustainable forms of energy.
What is agriculture?
Agriculture is a very important socio-economic activity in Iceland. Although much of the island is mountainous and unsuitable for agriculture, about 20 per cent of the land area is fertile because it is rich in volcanic minerals.
Name 3 things to do with agriculture in Iceland
• Crops such as tomatoes, cucumbers and peppers, as well as flowers, are grown in greenhouses that are heated using geothermal energy.
• The water used for the geothermal heating systems is reused to water the plants. This is an example of a sustainable use of water.
• Because Iceland is so far north, there are few hours of sunlight during winter. Cheap geothermal energy allows people in Iceland to create artificial light, which the plants need to grow.
