Geography year 9 Flashcards
What happens at a destructive boundary?
The oceanic pleate is denser than the continental plate so, as they move together, the oceanic plate is forced underneath the continental plate. The point at which this happens is called the subduction zone. As the oceanic plate is forced below the continental plate it melts to form magma and earthquakes are triggered. The magma collects to form a magma chamber. This magma then rises up through cracks in the continental crust. As pressure builds up a volcanic erruption may occur.
Name the 3 types of volcanoes
Composite cone volcano, acid lava volcano, shield volcano
Describe a composite come volcano
Steep sided symmetrical cone shape, high with narrow base, alternative layers of acid, lava and ash, lava may cool inside the vent and the next eruption is very explosive, subsidiary cones and vents form.
Describe an acid lava volcano
Very steep cone with narrow base (or spine), composed of acid lava which does not flow easily, very explosive eruptions.
Describe a shield volcano
Gentle slopes and wide base, frequent eruptions of basic lava, lava flows more easily and travels longer distance before cooling, usually non-violent.
What is the definition of an earthquake?
A sudden movement or tremor on the surface of the earth.
What is the epicentre?
The centre of the earthquake and the strongest part.
Kobe earthquake
Japan, Tuesday 17th January 1995 at 5:46am. Population of 10 million. Kobe is on a plate boundary between the Pacific, Philippines and the Eurasian plates. The Pacific plate is moving underneath the Eurasian plate, this is called a subduction zone. Destructive plate boundary (converging), i.e coming together.
Benefits of living near volcanoes
There is good soil to grow crops, It will bring more tourism, and more tourism jobs available; this will bring more money.
Problems of living near volcanoes
Transport and communication will be blocked; this will stop people getting out or police and ambulance getting in, as the lava flows will cover and block the roads.
Describe the climate of rainforests
In the morning the sun shines and heats up the ground, hot and wet air rises. In the afternoon dark clouds bring rain and thunderstorms to the rainforest. At night the sky becomes dark and the heat level drops; this is because there are no clouds to keep the heat in.
Waxy leaves
A waxy substance which coats the leaves to help the plant retain water.
Drip tips
Excess water drips off to prevent algae.
Impacts of human activity in the rainforest
Deforestation - slash and burn is when existing crops and vegetation are cut down and burnt, subsistence farming, commercial cattle ranching is when large transitional companies sell beef and burn the forest, replacing the trees with grass.
How has transport speeded up globalisation?
Easer and quicker to get to places.
