Earthquakes Flashcards
What is a seismograph?
An instrument used to detect and record earthquakes.
What is the richer scale?
The scale used to measure the strength of an earthquake, designed in 1934.
What is a fault?
Line of weakness in the Earth’s crust along which movement takes place.
What is a hypocenter/focus?
Location below the Earth’s surface where the earthquake starts and the faults start to rupture.
What are seismic waves?
Waves of energy that travel through the Earth’s layers and are a result of an earthquake.
What is a seismogram?
The recording that a seismograph makes.
What is a tsunami?
Large ocean wave created by undersea earthquakes
What is the Mecalli Scale?
A scale that uses the observations of people who experienced the earthquake to estimate its intensity.
What is a Moment Magnitude Scale?
The scale that was developed in the 1970’s to succeed the Richter Scale and measure the size of an earthquake based on the seismic moment.
Describe the sequence of an earthquake?
- Tectonic plates are together by friction.
- Pressure builds up due to movement in the Mantle.
- The rock breaks along a weak point(the fault line).
- The tectonic plates suddenly move.
- Stored energy is released as seismic waves.
- The earth’s surface shakes.
What is a primary effect?
Hazards during and right after an earthquake strikes.
What is a secondary effect?
Problems that occur hours or days after and earthquake.
In _____ there were _____ very strong earthquakes. That is almost one earthquake every ____ days. About _____ people died as a result of the earthquakes.
2010
175
Two
320 000
Where do earthquakes happen?
Along plate boundaries in the same areas as volcanoes.
In which year did the Haiti earthquake happen and how many people died?
In the year 2010 and 230 000 people died.
