Module 4 - Earthquake Related Hazards.pdf

EARTHQUAKE HAZARDS Norman P. Santos, LPT What is an Earthquake? An earthquake is a sudden release of energy in the Earth's crust that creates seismic waves. What causes Earthquakes? Most earthquakes occur due to the movement of tectonic plates, which are large pieces of the Earth's crust that fi...

EARTHQUAKE HAZARDS Norman P. Santos, LPT What is an Earthquake? An earthquake is a sudden release of energy in the Earth's crust that creates seismic waves. What causes Earthquakes? Most earthquakes occur due to the movement of tectonic plates, which are large pieces of the Earth's crust that fit together like a jigsaw puzzle.  Earthquakes in the Philippines Earthquakes have been occuring as part of Earth’s normal functioning. Earthquakes in the Philippines happen more frequently because of its geographical location. The Philippines is one of the countries situated near the Pacific Ring of Fire.  Potential Earthquake Hazards 1. Ground Shaking The shaking of the ground is caused by the passage of seismic waves, forms of energy that travel through the different layers of Earth caused by vibration or movement.  Potential Earthquake Hazards 2. Ground Rupture This occurs when ground movement happens on a fault line and breaks through to the surface.  Potential Earthquake Hazards 3. Liquefaction This occurs when seismic shaking causes loose materials in the soil to mix with groundwater or soil saturated with water.  Potential Earthquake Hazards 4. Earthquake-induced ground subsidence Subsidence is the lowering of land due to various cases, one of which is the earthquake on a fault line.  Potential Earthquake Hazards 5. Tsunami Tsunamis are giant waves caused by earthquakes or volcanic eruptions under the sea. As the waves travel inland, they build up to higher and higher heights as the depth of the ocean decreases.  Potential Earthquake Hazards 6. Earthquake-induced landslide Landslides may happen during or after an earthquake when a weekend section of landfalls off primarily due to gravity.  Early Warning Signs of Earthquake Hazards Faults are fractures or cracks in the Earth's crust where movement occurs. Zigzag Line Seismometer/Seismograph Means a detected tremor as A seismometer is an opposed to a plain straight instrument used to line where no movement is measure movements felt. in Earth’s surface. It Seismic Waves can detect vibrations from seismic waves Seismic wave is a form of generated by energy that travels through earthquakes and the interior of Earth. volcanic eruptions. 2 types: p-waves s-waves Interpreting Earthquake Hazard Maps  Before an Precautionary and Safety Measures BEFORE, earthquake DURING, and AFTER Prepare a survival kit. It should contain at least the following items: bottled water, canned goods and can opener, first aid kit, battery powered radio, flashlight with working batteries, and clothes. Avoid placing breakables on high shelves or cabinets. These items can easily fall even by a slight shake. Check regularly the stability of hanging objects such as ceiling fans and chandeliers. Make sure that these objects are securely fastened. Change the screws or tighten them if you notice any slight movements in these hanging objects. Fasten heavy furniture to the walls or floor. Tall cabinets can be secured by hooking them up against the wall. Know the emergency numbers of the police, rescue, and fire departments. Make sure all family members know these numbers. You fan display or post these numbers near tour telephone for easy reference.  During an If you are indoors: earthquake Stay calm. Remember the DCH method. DROP - Whatever you are doing or whatever position you are in, immediately drop down to the floor. COVER - Find a sturdy piece of furniture, such as table or a chair, and take COVER under it. It is important to protect your head and neck with your arms. HOLD - Hold on to the sturdy piece of furniture and prepare to move with it until the earthquake stops or when all other objects have stopped moving. 3Stay away from glass windows and doors, and heavy furniture. Watch out for falling or objects. Never use an elevator to get out the building.  During an If you are outdoors: earthquake Stay clear of buildings, trees, light posts, power lines, and other structures that could fall or collapse on you. If you are in a mountainous area, be alert for falling rocks and other debris. If you are in a coastal area, move to a higher ground in a coastal area, move to a higher in case a tsunami follows after the earthquake.  During an If you are driving or inside a car: earthquake Slow down and turn on the hazard lights to alert other drivers. Stay inside the car until the shaking stops. Avoid pulling up near or under bridges, overpasses, and power lines that may fall or collapse.  During an If you are on a bus or a train: earthquake Hold tightly to the strap or handrail. Stay inside and listen to the instructions of the train staff. Wait until it is safe to go out of the vehicle.  Expect aftershocks, so remain calm. After an Check yourself and others for injuries. earthquake Stay away from downed or damaged power lines. Check for damaged electrical wiring. Shut off the main electrical switch if you suspect any damage. Inspect gas tanks (by smell only) for leaks. Tune in to local radio stations and listen for any news and danger reports. Stay out of damaged buildings and areas with broken glass and debris. Follow the emergency plan or the instructions of building personnel if yo are inside a building. Thank You!!