What is earthquake? complete guidance

 

Earthquake is one of the natural disasters. The origin can be traced to the early days of the formation of the earth. It is responsible for a lot of damage to living organisms and non-living. For many centuries no man who does not know why earthquakes occur and how they occur and to what extent the damage will be. He believed he was the only one who was angry with Mother Earth and caused the earthquake and that he always feared.It was left to Aristotle, the great Greek philosopher, to link this phenomenon of the earthquake to physical factors. According to Aristotle, when the compressed air escapes into the bow, shake it part of the land. This is called the emission of volcanic activity. When the volcano exploded, and a lot of lava, gas and other out of the ground, and the failure of the exit. This causes a pressure imbalance and results in the production of earthquake waves in the surrounding areas. Thus has been identified that volcanic activity is one of the causes of earthquakes. Results of volcanic activity in the crack. To fill the new errors on the movement of the earth takes place. This causes the earthquake.The second reason is the isostatic adjustment. Earth's surface and some of the blocks and barriers set up a certain depression. They keep the balance of the earth, and when the rotor moves the units of the axis. Raised these blocks until it is washed down due to various reasons, and why the imbalance. Earthquakes also occur and then to restore and maintain this balance.We can see that earthquakes usually occur in areas volcano Prime Minister and under the feet of the hills and mountains, as well as any settlement earthquakes occur frequently in China, Japan, the Philippines, and southern parts of the Himalayas, cut off Prime Minister volcano in Europe and parts of North West and South America. It is also likely to occur in the state of Rajasthan in India and Arab countries.One can not say that earthquakes do not occur in other places. They may occur in any part of the world at any time. We are not sure of the very radical Islamic movements from the ground and pressure points and the session. Only in this way one can determine the areas, are likely to occur.All earthquakes do not cause serious damage. Those that are of high density is really dangerous. There are standards to measure the intensity of the earthquake. It was the first one in the scope of Mercall. Is the measure of a qualitative, not quantitative scale, and so are not useful for measuring the density. The second is the Richter scale. Is released from inside the Richter scale. Measured with numbers. If the earthquake measures 7 points on the Richter scale, it causes severe damage because of severe intensity. Perhaps those measuring 5 points and less do not cause much damage.Scientists are now able to study and determine the secondary waves and higher education also in the waves of earthquakes. Scientists are able to study the radical Islamic movements in the wave of the help of a device called a seismograph. Helping one can also predict the possibility of an earthquake is likely, "Where and when is likely to happen.In India more than earthquakes occur in the Himalayas, the Ganges and Brahmaputra valleys. Was signed by only a few earthquakes in the Deccan Plateau. Earthquake, which occurred in 1967 in Icwyna and the earthquake in 1993 in the state of Maharashtra in the last Latour are in this area.And can in this respect than men of natural disasters can not be the only master he becomes a master of nature altogether. This is not possible for a man with limited knowledge of nature has in his leadership.

What is a landslide?

A landslide in the first place is a set of geological processes, which include several movements such as land slope failure and a wide range, falling rocks, and debris flow. This may be terrestrial movements occur in the coastal marine environment, and land. Gravity is the main force that causes landslides, in addition to other benefits that affect the stability of the ground.Usually, the characteristics of the ground, especially the development of subsurface soil conditions that cause the failure of the slope. However, the collapse of the real need to trigger before you can start on it. It is usually possible to identify the origin of the main players landslide victory. Process may be the trigger with respect to weather, or the stimulus that produces an immediate reaction of the slope. Typically, the establishment of such a movement because of a change in the stresses of the slope. These types of geological formations are common in mountainous areas. It will be necessary to install the slopes to reduce the likelihood of landslides.
Triggers landslide:
May be caused by landslides due to many reasons may be active individually or together. Some of the main reasons are:
Rain wide:
Landslide on the trigger was the most rainfall intensity for long periods and heavy. May also occur on the trigger, even if the density of moderate rain, but rain and a high pore pressure. The global survey revealed overwhelming, which was held in 2003, which was activated 90% of the landslides and signed by the heavy rainfall. In the first place, and this is due to step up pressure of water in the pores of the soil.
Melting ice:
In many places the mountain cold, melting snow and frequent, and may be vital to the process of landslides. This is particularly important when the rapid increase in temperature quickly begins melting snow. Production of water seeping into the ground under the layers of impermeable surface. And pore water pressure increased rapidly, causing a landslide at the beginning of the process. This result is particularly important when it is complete weather is hot before adding the rainfall into the groundwater and increase the rate of melting.
Rivers:
Can damage the slopes of the rivers, especially during floods, which caused a landslide. Disorder increases the slope of the gradient slope, and the reduction of stability. In some countries, has been observed in many cases, this process after the floods caused by glacial erosion of a finger along the canal. The flood waves pass, and the earth and the wide sliding usually occurs. This volatility will last for a long time, especially during the subsequent periods of heavy rain and flooding.
Change in water level:
May lead to rapid changes in the ground water level along the slope leading to landslides. This is especially true when the slope of the nearby river or other body of water. As the water level near the slope decreases rapidly, ground water can not dissipate quickly, causing a high water table. Exposed to high shear stress ramp that leads to potential instability. This is one of the most important way in which the river bank fails.
Seismic shaking:
Seismic waves through the rocks and the ground accelerations that creates a change from the forces of gravity on a slope. Change the vertical acceleration, respectively, the load on the slope. Acceleration caused by the horizontal shear force due to inertia overwhelming. This complex process, and can be sufficient to cause the failure of the slope. These operations are large in mountainous areas where seismic waves cause an increase in the acceleration of the earth. This is called the development of topographic amplification. The greatest acceleration usually occurs at the top of the slope or near the line of hills.
Liquefaction:
Can not be the movement of earthquake waves through the earth produces liquefaction. During this process, and the shaking causes the lower area of ??the pores. High density of pore pressure increase in the ground. Granular materials are changed to the flow of slides that are fast and can be very devastating.
Landslide warning technology:
And the physical destruction and loss of life caused by landslides fears of many people. So, put the sensors that are used for landslide warning and detection by monitoring the slope, displacement, and rainfall, and flow. A careful analysis of these data help to identify weaknesses and pressure of underground water. Data on the rate of movement of the slide are available that can predict the state of the landslide. Geotechnical analysis can, including the study of the stability of the slope, and seismic behavior, and assessment of the site is useful to provide early warning of a landslide. Sensors can also provide early information about severe weather, and slope conditions that are unsafe.