Bangladesh in Risk of Earthquake: What Can Be Done. Presented By : Md.Jahangir Alam Coordinator, Disaster Management Unit Dhaka Ahsania Mission

Transcription

1 Bangladesh in Risk of Earthquake: What Can Be Done Presented By : Md.Jahangir Alam Coordinator, Disaster Management Unit Dhaka Ahsania Mission

2 What are Earthquakes? The shaking /ground vibration caused by the sudden/abrupt release of energy Usually associated with faulting or breaking of rocks Continuing adjustment of position results in aftershocksw 2

3 Richter s Scale & Measuring Earthquakes Earthquakes are recorded by a Seismograph it draws graphs called Seismograms and represents the propagating waves. The Richter scale is a scale that designs a number to earthquakes for quantify the energy released. 3

4 Measurement of Magnitude Magnitude Effects 3.5 or Less Don t Fell Cause Minor Damage Causing Damage to Building Cause Several Damages Cause Serious Damages 8.0 or More Total Destruction 4

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6 Different types of plates movement 6

7 The Focus and Epicenter of an Earthquake The point within Earth where faulting begins is the focus, or hypocenter The point directly above the focus on the surface is the epicenter

8 What are Seismic Waves? Response of material to the arrival of energy fronts released by rupture Two types: Body waves P and S Surface waves R and L

9 Body Waves: P and S waves Body waves - P or primary waves fastest waves travel through solids, liquids, or gases compressional wave, material movement is in the same direction as wave movement S or secondary waves slower than P waves travel through solids only shear waves - move material perpendicular to wave movement

10 Surface Waves: R and L waves Surface Waves Travel just below or along the ground s surface Slower than body waves; rolling and side-to-side movement Especially damaging to buildings

11 The Economics and Societal Impacts of EQs Building collapse Fire Tsunami Ground failure

12 Can Earthquakes be Predicted? Earthquake Precursors changes in elevation or tilting of land surface, fluctuations in groundwater levels, magnetic field, electrical resistance of the ground seismic dilatancy model seismic gaps

13 Can Earthquakes be Predicted? Earthquake Prediction Programs include laboratory and field studies of rocks before, during, and after earthquakes monitor activity along major faults produce risk assessments

14 Can Earthquakes be Controlled? Graph showing the relationship between the amount of waste injected into wells per month and the average number of Denver earthquakes per month Some have suggested that pumping fluids into seismic gaps will cause small earthquakes while preventing large ones

15 Earthquake zones of BD 15

16 Faults and tectonic contacts of Bangladesh

17 Population under different earthquake zones

18 Foundation failure and fault of Dhaka city

19 Liquefaction hazard of Dhaka city

20 Subsidence hazard of Dhaka city

21 Family Readiness Create a family Earthquake plan Know the safe spot in each room Know the danger spots Decide where your family will reunite if separated Keep a list of emergency phone numbers Develop a survival kit for work, car, and home

22 Home Preparedness Learn how to shut off gas, water, and electricity Check chimneys, roofs, and wall foundations for stability Secure heavy furnishings Secure water heater and appliances Keep heavy objects on lower shelves Maintain emergency food, water, medicine, first aid kit, tools, and clothing

23 Emergency Supplies First Aid supplies Band-Aids antibiotic ointment latex gloves cold/hot packs ace bandages arm sling Tylenol or Advil diarrhea medication Equipment work gloves shovel tents sleeping bags ready to eat foods clothing radio, flashlights CASH

24 During an Earthquake Stay away from windows, bookcases, file cabinets, heavy mirrors, and other heavy objects that could fall Duck under a desk or sturdy table Watch for falling plaster or ceiling tiles Stay undercover until the shaking stops, and hold onto your cover If the desk or table you are under moves move with it If in your car, stop, but not on a bridge, or under trees or a power line If outside, stay outside, and move to an area clear of overhead trees, power lines, or objects that could fall from a structure Don t forget about aftershocks

25 After The Earthquake Be prepared for aftershocks, plan for cover when they occur Check for injuries, give first aid as necessary Remain calm, try to reassure others Wear shoes to avoid injury from broken glass Check for fire and take appropriate actions Check gas, water, and electric lines Tune to emergency broadcast system on radio

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