DRRR

• Earthquake, (also known as quake, tremor or temblor) is a weak to violent shaking of the ground produced by the sudden movement of rock materials below the earth’s surface. ​
• Earthquake, a wave-like movement of the earth’s surface and may classified as tectonic or volcanic
• Volcanic Earthquake, are produced by movement of magma beneath volcanoes.​
• Tectonic Earthquakes​,

  • are produced by sudden movement along faults and plate boundaries. ​
• Focus, actual location beneath the surface where the earthquake begins.​
• Epicenter, point on the earth’s surface located directly above the focus of an earthquake. ​
• Fault, refers to a fracture, fissure, or a zone of weakness where movement has occurred. ​
• A fault divides rock into two fault blocks​, the hanging wall and footwall
• For any inclined fault, the block above the fault is the hanging wall block, and the block below the fault is the footwall block
• Normal slip, dip-slip faults on hich the hanging wall moves down relative to the footwall.​
• Reverse slip, Also know as thrust. Dip-slip faults on which the hanging wall moves up relative to the footwall.​
• Classification of STRIKE-slip faults​: RIGHT-LATERAL (DEXTRAL) FAULTS​ and LEFT-LATERAL (DEXTRAL) FAULTS​
• RIGHT-LATERAL (DEXTRAL) FAULTS​, Strike-slip faults across which the block moves to the right.​
• LEFT-LATERAL (DEXTRAL) FAULTS​

  Strike-slip faults across which the block moves to the left.​
• Oblique-slip Fault​, Combination of dip-slip and strike-slip fault​
• • Energy released at the source of the earthquake and determined by seismographs.​
• Magnitude is amount of energy coming from the focus.​
• Intensity is strength of shaking produced by the earthquake at a certain location​

  Indicates the perceived effects of the earthquake in an area, which may vary according to what the affected residents may experience and observe.​
• Seismograph is an instrument that records an earthquake​
• seismograph​

  Records intensity, height and amplitude of seismic  waves.​
• seismometer​

  Instrument that detect seismic waves​
• sesimometer sensor that detects ground motion​
• seismogram record of earthquake retrieved from a seismograph ​
• Aftershock, usually weaker earthquakes that follow the main shock of an earthquake’s sequence. Usually occurs soon after major quake. Not all energy gets released during major event
• Foreshock​, Small quake preceding major quake​. Can happen days or possible years before major quake.​
• SEISMIC WAVES​: Body waves and Surface waves
• P waves​, Parallel​ and Push-Pull. Compress and Expand. Particles move in same direction as waves. Travel faster than S waves​. Can go through liquids and solids​
• s waves​, Perpendicular​ and Particles move at right angle to waves’ direction. Also called transverse waves​. Travel slower than P waves. Travel through solids only​
• Surface waves​: Rayleigh waves​ and Love waves​
• Rayleigh waves Travel near the surface of solids. Rayleigh waves include both longitudinal and transverse motions that decrease exponentially in amplitude as distance from the surface increases. There is a phase difference between these component motions.​
• Love waves (also known as Q waves (Quer: German for lateral)) are surface seismic waves that cause horizontal shifting of the Earth during an earthquake.​
• POTENTIAL EARTHQUAKE HAZARD : 1. Ground Shaking, 2. Ground ruptures, 3. Liquefaction, 4. Tsunami, 5. Earthquake induced landslide, 6. Earthquake induced Ground subsidence
• Ground Rupture is a displacement on the ground due to the movement of fault ​
• Ground shaking is a disruptive up-down and sideways movement or motion experienced during earthquake ​
• Liquefaction is aMixing of sand or soil and water underground during the shaking od a moderate or strong earthquake ​
• Tsunami is a sea waves resulting from the disturbance of ocean floor by an earthquake​
• Earthquake induced landslide ​occurs when failures in steep or hilly slopes triggered by an earthquake ​
• Landslides is a loose rock and soil on slopes move​
• Mudflow is a water content of soil is high​. Soil and water slide downhill​
• Earthquake induced ground subsidence, ​a gradual settling or sudden sinking of the earth’s surface​