26-06-2017, 11:56 AM
Projet on disaster management earthquake class9
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project on disaster management earthquake class 9
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Projet on disaster management earthquake class9
29-06-2017, 02:20 PM
India is very vulnerable to earthquakes, with more than 60% of earth prone to earthquakes of Richter Intensity 7.0 and higher, which can cause structural damage. Earthquakes continue to cause large-scale human deaths, most of which are due to the collapse of man-made structures. Recent earthquakes have revealed the country's lack of preparedness to deal with its impacts. Since short- or medium-term prediction of earthquakes is difficult, seismic safety of built environments that ensure structures do not collapse is an important cornerstone of earthquake mitigation efforts.
Earthquakes refer to the earthquake. There is continuous activity going under the surface of the earth. There are several large plates (size of continents) below the surface of the earth, which move (at a very slow speed). As part of this movement, they sometimes collide with each other. And, after the collision, they could still push on each other. As you continually keep pushing each other, there is increasing pressure - through these plates beneath the surface. And then, at one point, one of the dishes could slide over another. This causes an earthquake.
Some earthquakes can be caused by surface activity. For example, in a mountainous region, there could be a heavy landslide. Due to a large mass of land falling, at the point of fall, there could be a minor earth tremor, due to the impact of the fall. However, such earthquakes are generally not very important.
The risk of the earthquake in India
The growing population of India and its extensive non-scientific constructions are multiplying everywhere, including multi-storey luxury apartments, large factory buildings, gigantic shopping centers, supermarkets, warehouses and masonry buildings. Over the past 15 years, the country has experienced 10 major earthquakes which have resulted in more than 20,000 deaths. According to the current map of the country's seismic zone (IS 1893: 2002), over 59% of India's surface is threatened with moderate to severe seismic hazard; This means that it is prone to shake from MSK Intensity VII and higher (BMTPC, 2006). In fact, the entire Himalayan belt is considered prone to large earthquakes of magnitude greater than 8.0; And in a relatively short span of about 50 years, four earthquakes of this type have occurred: 1897 Shillong (M8.7); 1905 Kangra (M8.0); 1934 Bihar - Nepal (M8.3); Y 1950 Assam-Tibet (M8.6). Scientific publications have warned of the likelihood of very serious earthquakes occurring in the Himalayan region, which could negatively affect the lives of several million people in India.
At one time the country's regions away from the Himalayas and other inter-plate boundaries were considered relatively safe from harmful earthquakes. However, in the recent past, even these areas have experienced devastating earthquakes, albeit of a smaller magnitude than the Himalayan earthquakes. The Koyna earthquake in 1967 led to a review of the seismic zoning map, which resulted in the removal of the non-seismic zone from the map. The areas surrounding Koyna were also re-designated to Seismic Zone IV, indicating high risk. The occurrence of the Killari earthquake in 1993 resulted in a new revision of the seismic zoning map in which the low-risk area or seismic zone I merged with seismic zone II, and parts of Deccan and peninsular India were included In seismic zone III, zones designated as moderate risk areas. Recent research suggests that as the understanding of the seismic hazard of these regions increases, more areas assigned as low risk may be re-designated to a higher level of seismic risk, or vice versa.
The northeastern part of the country continues to experience moderate to large earthquakes at frequent intervals including the two major earthquakes mentioned above. Since 1950, the region has experienced several moderate earthquakes. On average, the region experiences an earthquake with a magnitude greater than 6.0 every year. The Andaman and Nicobar Islands are also located on an inter-plateau border and often experience damaging earthquakes.
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