1.1 Characteristics, distribution, measurement of earthquake Flashcards
What is a Natural event
A volcanic eruption, drought, flood or Tsunami that occurs but has no risk to human life or property
What is a Natural hazard
Something that is potentially dangerous to people. This involves the human population placing itself at risk from the natural event
What is a Natural disaster
Where an event is much larger than expected, and there is excessive damage to life and property.
What are tectonic hazards
hazards that occur due to proceses within the earth e.g earthquakes
5 factors that affect the risk of a hazard
technology
wealth
age
location
education
what are earthquakes
An earthquake is a series of vibrations or shock waves (1) among the rocks in the Earth’s crust (1).
what are seismic waves
The earthquake’s energy is released in seismic waves and they spread out from the focus. Theseismic wavesare most powerful at the epicentre.
what is the epicentre
the point on the Earth’s surface directly above the focus.
what are the 3 different types of scales used to measure earthquakes
mercali scale
ritcher scale
moment magnitude scale
what tool and measurment is used to measure earthquakes
the tool is a seismometer and the measurment is magnitude
what does the ritcher scale measure
the ritcher scale Measures the energy released by an earthquake on a logarithmic scale assessing the amount of rock movement along a fault or fracture in the surface.
what does the mercali scale measure
the mercali scale measure the intensity of an earthquake by describing what people experience and the amount of damage done.
what does the moment magnitude scale measure
the mment magnitude scale measures the magnitude of an earthquake (how powerful it is). It is measured using a machine called aseismometer.
What is the point on earths surface directly above the focus called?
The epicenter
What is the focus?
The point inside the Earth’s crust where the earthquake originates from is known as the focus.
