4 Flashcards
a trembling or a shaking movement of the ground, caused by the slippage or rupture of a fault within the Earth’s crust
earthquake
a weak to violent shaking of the ground produced by the sudden movement of rock materials below the earth’s surface.
earthquakes
earthquakes originate in ______
tectonic plate boundary
is point inside the earth where the earthquake started
focus / hypocenter
The focus is point inside the earth where the earthquake started, sometimes called the ______
hypocenter
the point on the surface of the earth directly above the focus is called the _______
epicenter
how many ways to measure a strength of an earthquake
2 - magnitude / intensity
is proportional to the energy released by an earthquake at the focus.
magnitude
It is calculated from earthquakes
recorded by an instrument called seismograph
magnitude
It is represented by Arabic Numbers (e.g. 4.8, 9.0).
magnitude
_______ on the other hand is the strength of an earthquake as perceived and felt by people in a certain locality.
Intensity
numerical rating based on the relative effects to people, objects, environment and structures in the surrounding.
intensity
is generally higher near the epicenter. It is represented by Roman Numerals (e.g. II, IV, IX). In the Philippines
intensity
is an earthquake of similar or lesser intensity that follows the main earthquake.
aftershock
sudden slipping or movement of a portion of the earth’s crust accompanied and follow by series of vibrations.
earthquake