The people living in mountainous areas are well aware of the collapse. There, this phenomenon is common, nevertheless quite formidable, capable of causing terrible destruction and human casualties.
How do landslides form?
This natural phenomenon is the rapid separation and movement of rocks under the influence of gravity along the slopes with overturning, crushing, as a result of which the bottom of the valley is covered with debris.
Sometimes large blocks collapse, splitting in the process of falling into many small fragments, turning into rockfall. The magnitude of the collapses can have different limits - from the collapse of small pieces of rocks to huge masses of several million cubic meters.
The causes of collapses are most often caused by weakening of rocks, violation of their integrity, the formation of cracks, which is the result of weathering, leaching of soil by ground and surface waters. This process is also affected by the geological structure of the area, tremors and, to a large extent, human activity when the rules of construction and mining are violated.
Classification
Collapses are characterized by the power of the process (the volume of falling rock masses) and the scale of manifestation, determined by the area. In this regard, they are divided into very small, the volume of which is not more than 5 m 3 , small (from 5 to 50 m 3 ), medium (from 50 to 1000 m 3 ) and large (more than 1000 m 3 ). An example of what a collapse on a gigantic scale showed the collapse of rocks in the Pamir mountains in 1911, the volume of which amounted to about 2 billion m 3 .
Depending on the scale of manifestation, huge (more than 100 ha), medium (from 50 to 100 ha), small (5 to 50 ha) and small (up to 5 ha) landslides are distinguished.
Consequences of collapses
The greatest danger is represented by heavy rocks, which, collapsing and falling from the slopes, are able to crush or fall asleep even the strongest buildings. They overwhelm the surrounding space, sometimes hiding entire settlements, agricultural areas and forests under themselves. Sometimes such landslides and mudflows destroy the banks of rivers, which threatens with floods that bring no less significant damage to nature and the national economy. Such catastrophic phenomena not only harm the economy, lead to death of people, but also often cause a change in the landscape.
Snowfall
These landslides also have to be reckoned with. They happen in high mountain areas, where accumulated snow sometimes rolls down in the form of an avalanche. Most often this happens on treeless slopes, the slope of which is at least 140 degrees. At the same time, huge snow mass moves at a speed of 30 to 100 m / s, destroying structures on its way, filling roads and mountain trails. The tourists, residents of villages and other people who have appeared on its way can be covered with snow.
The impact from such an avalanche can have a force of up to 50 tons per square meter. Similar natural disasters in Russia most often occur on the Kola Peninsula, the North Caucasus, the Urals, the Far East and
Western Siberia.
The snow avalanche can be triggered by intense snowmelt, snowing for a long time, as well as earthquakes and any significant fluctuations in air resulting from human activities.
Precautionary measures
Residents living in mountainous areas are well aware of what a collapse is and, as a rule, carry out certain measures to strengthen territories and houses for the purpose of protection. Stations and posts of hydrometeorological services are obliged to inform the population in a timely manner about the danger associated with landslides and their area of effect.
Laying a railway track in the mountains requires careful identification of sections unsuccessful in the collapses in order to get around them if possible. Particularly steep slopes during the construction of roads are laid with stone. During the development of quarries, the nature of the rocks, the direction of the cracks are studied in order to exclude the shedding of the overlying layer.
Actions in the event of a collapse
Natural disasters in the form of landslides or landslides can have the most unpleasant consequences. Therefore, upon receipt of information about their possible threat, the entire population living in this territory, together with property, as well as farm animals are evacuated to safer places.
This is done in accordance with the established procedure. If time permits, before evacuation it is necessary to carry out preparatory work - to remove all property inside the house, tightly closing the doors and windows. Be sure to turn off the electricity, water and gas.
People warn each other about danger. In case of a landslide threat, an emergency exit is to the safe slopes of the mountains or elevations. Climbing them, you can not move along gorges, ditches and valleys, so as not to fall into the channel of the mudflow.
To return to the previous place when the landslide or the landslide movement ends, you can only be fully convinced of the absence of a threat. Only in this case it is worthwhile to search for missing people and provide assistance to the victims. Knowing what a collapse is, local residents of the highlands usually know how to behave in such situations, and are ready at any time to quickly pack up and evacuate to a safe place.