Slide 1: Earthquake An earthquake (also known as a tremor or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves Slide 2: Earthquakes strike suddenly, without warning Earthquakes can occur at any time of the year and at any time of the day or night On a yearly basis, 70 to 75 powerful earthquakes occur throughout the world An earthquake is a sudden, rapid shaking of the Earth caused by the movement of huge plates that form the surface of the Earth Slide 3: Sometimes the plate movement is gradual At other times, the plates are locked together, unable to release the accumulating energy The plates break free causing the ground to shake Slide 4: Most earthquakes occur at the boundaries where the plates meet Slide 5: Some earthquakes occur in the middle of plates An earthquake is just like throwing a stone in a pond of water Slide 6: The point of disturbance below the surface of the Earth is called, FOCUS Slide 7: The point directly above the FOCUS on the surface of the Earth is called, EPICENTRE Slide 8: The vibrations are called SEISMIC WAVES Slide 9: The study of earthquake waves is known as SEISMOLOGY The experts who study the pattern of earthquakes are known as SEISMOLOGISTS The machine which records the intensity of earthquake is known as SEISMOGRAPH Slide 10: The recordings of the SEISMOGRAPH are converted into the actual intensity of the quake by using RICHTER SCALE Slide 11: Richter scale was invented by Charles Richter in 1935 Earthquakes measuring above 6 on the scale are very destructive Earthquakes are experienced in the same regions where volcanoes are situated Slide 12: Earthquake in INDIA Himalayan region is prone to earthquakes Deccan plateau had earthquakes rarely and is considered safe from earthquakes Slide 13: Some destructive earthquakes rocked India Uttarkashi (Uttarkhand) 1991 Latur (Maharashrta) 1993 Jabalpur (Madhya Pradesh) 1997 Chamoli (Uttarkhand) 1999 Bhuj (Gujarat) 2001 Jammu & Kashmir 2005 Pak- Occupied Kashmir 2007 Slide 14: Assignment for the day Define earthquake. What is the reason for the shaking of the earth? What is focus? What is epicentre? Define seismic waves? How do they travel? Explain the measurement of earthquakes. Why do earthquakes take place in the plate boundaries? Slide 15: Kobe Earthquake, 17 jan 1995 Japan is a country affected by earthquakes. It is located where the EURASIAN plate, PACIFIC plate and the PHILIPPINE plate meet.