OCR B Geography GCSE Paper 1 concepts and definitions: Chapter 2, How can tectonics be hazardous?

How do tectonic plates move?

• They are constantly bouncing off of each other, sending them in the opposite direction

• They are dragged by convection currents in the mantle underneath

• Theres some really strong dude in the core pushing them around

Where is continental crust found, and how thick is it?

• Under continents, between 25-100 Km thick

• Under continents, between 10-25 Km thick

• Under oceans, between 25-100 Km thick

• Under oceans, between 10-25 Km thick

What land forms would you expect to find at a destructive plate boundary, between two continental plates?

• Fold mountains

• Fissures

• Rifts

• Volcanic ridges

What is an example of a constructive boundary?

• San Andreas fault

• Iceland

• Phillipines

• Himalayas

Where is the epicentre of an earthquake found?

• At the exact point from which seismic waves radiate out

• The point directly above the focus, on the surface of the land

What type of scale is the Richter scale?

• Logarithmic

• Linear

What does the Mercalli scale measure?

• Intensity of seismic waves during an earthquake

• Distance moved by plates after an earthquake

• Intensity of the impacts of an earthquake

1 limitation of the Mercalli scale?

• It is subjective

• Can't be used to compare impacts with other earthquakes

• Doesn't assess damage to buildings

Highest intensity ever recorded (Richter scale)

• 9.5

• 9.6

• 9.2

• 8.9

Where is molten rock found?

• The mantle

• The core

• The crust