DRRR 4

• GEOLOGY: the science that deals with the dynamics and physical history of the earth, the rocks of which it is composed, and the physical, chemical, and biological changes that the earth has undergone or is undergoing.
• GEOLOGIST: a scientist who studies the solid, liquid, and gaseous matter that constitutes the Earth and other terrestrial planets, as well as the processes that shape them.
• GEOLOGIC HAZARD: one of several types of adverse geologic conditions capable of causing damage or loss of property and life.
• EARTHQUAKE: also known as a quake, tremor or temblor. Is the perceptible shaking of the surface of the earth, resulting from the sudden release of energy in earth's crust that creates seismic waves.
• USGS: US Geological Science
• SEISMOLOGY: the study of earthquakes and seismic waves that move through and around the earth.
• SEISMOGRAPHY: the scientific measuring and recording of the shock and vibrations of earthquakes.
• SEISMOLOGISTS: scientists who study earthquakes and planetary activities as well as their effects, such as tsunamis.
• POTENTIAL EARTHQUAKE HAZARD: an earthquake is a type of hazard that depends on the strength of the seismic activity , along with such factors as local topographic and built features, subsurface geology and groundwater,
• GROUND SHAKING OR GROUND MOTION: Earth shakes with the passage of earthquake waves, which radiate energy that had been "stored" in stressed rocks, and were released when a fault broke and the rocks slipped to relieved the pent-up stress.
• The strength of ground shaking is measured in the velocity of ground motion, the acceleration of ground motion, the frequency content of the shaking and how long the shaking continues (duration).
• GROUND OR SURFACE RUPTURE: an offset of the ground surface when fault rupture extends to the Earth's surface. Any structure built across the fault is at risk of being torn apart as the two sides of the fault slip past each other.
• SOIL LIQUEFACTION: a phenomenon in which the strength and stiffness of a soil is reduced by earthquake shaking or other rapid loading. It normally occurs in saturated soils, that is, soils in which the space between individual particles is completely filled with water.
• EARTHQUAKE-INDUCED GROUND SUBSIDENCE: Subsidence or lowering pf the ground surface, often occurs during earthquakes. This may be due to downward vertical displacement on one side of the fault, and cam sometimes affect a huge area of land.
• EARTHQUAKE - INDUCED LATERAL SPREADING: Lateral spreading occurs where sloping grounds starts to move downhill, causing cracks to open up, that are often seen along hill crests and river banks.
• EARTHQUAKE - INDUCED LANDSLIDE: Landslides are frequently triggered by strong ground motions. They are important secondary earthquake hazard. The term landslide includes a wide range of ground movement, such as rock falls, deep failure of slopes, and shallow debris flow.
• TSUNAMI: also known as a seismic wave, is a series of waves in a water body caused by displacement of a large volume of water, generally in an ocean or lake.
• Natural signs of an Impending Tsunami: Animal Behavior and Drawback
• Animal Behavior: Zoologists hypothesize that some animal species like elephants have the ability to sense subsonic Rayleigh waves from an earthquake or tsunami.
• Drawback: this is an observable natural sign of an impending tsunami that is noteworthy.
• VOLCANO: is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
• LAVA: a molten rock that has been expelled from the interior of some planets (including Earth) and some of their moons.
• MAGMA: is composed of molten rock and is stored in the Earth's crust.
• TEPHRA: a general term for airborne pyroclastic material ejected during the course of a volcanic eruption.
• VOLCANOLOGY: the discipline of the geologic sciences that is concerned with all the aspects of volcanic phenomena.
• LAHAR: a specific kind of mudflow made by volcanic debris.
• • Lahars move rapidly down valleys like rivers of concrete
• • Lahars can occur with or without volcanic eruption.
• • Lahars pick up as they travel, which can cause damage to structures in their path.
• ASH FALL: Volcanic ash consists of fragments of pulverized rock, minerals, and volcanic glass created during volcanic eruptions and measuring less than 2mm in diameter.
• PYROCLATIC FLOWS: contains a high-density mix of hot lava blocks, pumice, ash, and volcanic gas. They move at very high speed down volcanic slopes, typically following valleys.
• VOLCANO GASES: Magma contains dissolved gases, which provide the driving force that causes most volcanic eruptions. As magma rises towards the surface and pressure decreases, gases are released from liquid portion of magma and continue upward and are eventually released into the atmosphere.
• LAVA FLOWS: streams of molten rock that pour or ooze from an erupting vent. Lava is erupted during either non - explosive lava fountains.
• BALLISTIC PROJECTILE: are rocks that an erupting volcano may hurl into the air. These blocks and bombs travel like cannonballs and usually land within 2km of the vent.
• PHIVOLCS: Philippine Institute of Volcanology and Seismology
• Philippine Institute of Volcanology and Seismology : is a Philippine national institution dedicated to provide information on the activities of volcanoes, earthquakes, and tsunamis and services primarily for the protection of life and property.
• RAINFALL-INDUCED LANDSLIDE: it is generally triggered by other natural hazard such as prolonged, heavy rainfall or by other sources of water which increase the water content of the slope materials.
• SINKHOLES: common where the rock below the land surface is limestone, carbonate rock, salt beds or rocks that can naturally be dissolved by groundwater circulating through them.
• Types of sinkhole: Dissolution sinkhole, Cover-Subsidence sinkhole, cover collapse sinkhole.
• Dissolution sinkholes: dissolution of the limestone or dolomite is most intensive where the water first contacts the rock surface.