Plate Tectonics Flashcards
What is a natural event?
A natural event is something that happens naturally but doesn’t effect people
What is a natural hazard?
A natural hazard is something that happens but does effect people, eg, an earthquake
What is the inner core?
The inner core is the centre of the earth it is made of solid metal, is 750 miles wide and is 2760’c
What is the outer core?
The outer core is made of liquid rock (nickel and iron) and is 1400 miles wide
What is the mantle?
The mantle is below the crust it is made of hard and soft rock
What is the crust?
The crust is 20-60 miles wide ( continental), 3-6 miles wide ( oceanic )
What are tectonic plates?
Massive slabs of rock that make the earths crust
What are plate boundaries?
The place where two plates meet
What are convection currents?
The currents in the mantle that make the plates move
What happens at a constructive plate margin?
The plates are moving apart, this cause magma to rise and form new oceanic crust. This results in u detested volcanoes and countries such and Iceland
What happens at a conservative plate margin?
The two plates are sliding past each other. They get stuck on each other and cause tension, when the tension is released and earthquake occurs. An example is the San Andreas fault line.
What happens at a collision plate margin?
The two plates are moving towards each other. Both plates are continental, the crust is crumpled upwards to form fold mountains, an example is the Himalayas where the Eurasian plate has collided with the Indian plate
What happens at a destructive plate margin?
The two plates are moving towards each other, however the oceanic plate is being pushed under the continental plate as it is denser l, this forms a trench. Volcanoes are formed here
What is the epicentre?
The centre of the earthquake above land
What is the focus?
The centre of the earthquake below land, aka the start of the quake