Earthquake

• Reverse fault - also known as thrust fault, sliding one block of crust on top of another. This fault is commonly found in collisions zones.
• Normal faults - two blocks of crust pull apart create space, stretching the crust into a valley. In a normal fault, the hanging wall drops down.
• PHIVOLCS – (PHILIPPINE INSTITUTE OF VOLCANOLOGY AND SEISMOLOGY) mandate to mitigate to disasters that may arise from volcanic eruptions, earthquakes, tsunami and other related geotectonic phenomena.
• Earthquake - An earthquake is a shaking of the ground caused by movements of the earths crust.
• The lithosphere is composed of the crust layer and the upper portion of the mantle.
• Tectonic plates are massive, irregularly shaped slabs of solid rock, generally composed of both continental and oceanic lithosphere.
• Plate boundaries - edges where two plates meet
• Focus is the area inside the Earth where an Earthquake starts. It is also known as the focal point.
• Epicenter is the point on the Earth's surface directly above the focus.
• Magnitude measures the energy being released from the focus.
• A seismograph is an instrument that measures the earthquake's magnitude.
• Richter (Magnitude) Scale - measures the seismic energy released by the earthquake.
• Intensity is the strength of the trembling made by the earthquake at a place or on the surface.
• Mercalli Scale measures the intensity of an earthquake
• Active faults are areas along which displacement is expected to occur.
• Inactive faults are areas which can be identified but which do not have the occurrence of an earthquake.