Sel is a destructive stream

Sel is a turbulent stream in which there isa large concentration of fragments of rocks, stones and mineral particles. Their quantity can exceed half the volume of all the water present in it. The natural disaster - the village - suddenly appears in the basins of small mountain rivers. Most often, the main cause of its occurrence is a sharp melting of snow or heavy rainfall.

General information

The consistence of the flow is intermediatesubstance between solid and liquid mass. Sel is a phenomenon that is relatively short-lived and lasts no more than three hours. Primarily occurs in small watercourses, the length of which does not exceed 30 kilometers.

Characteristics

The velocity of such flows is inrange from 2 to 6 meters per second. This is due to their destructive effect. Sel is a stream that creates deep channels in its path. They usually contain small streams or are completely dry. The components that make up the stream accumulate on the plains in front of the mountains. The movement in the form of the water shaft of its frontal part is typical for the mudflow. Most often there is a series, which consists of alternately replacing each other shafts. When the selenium comes off, the consequences almost always represent a strong change in the shape of the channel.

Causes of appearance

Sel is a stormy natural phenomenon. The stream may appear due to the rapid melting of glaciers, seasonal snow massifs or prolonged and intense rainfall. Also, the reason for the occurrence may be the ingress of a huge amount of loosely fragmented objects into the channel. Deforestation in the mountainous terrain is one of the main factors in the appearance of a rapid flow. In preventing the occurrence of mudflow, trees play an important role, since their roots hold the upper layer of the soil. In dry logs with a large slope and in the basins of small mountain rivers, destructive flows appear rarely. Seley can be classified. There are landslide-landslide, breakthrough and erosive types of origin of this phenomenon.

Outbreaks

Potential places for floware the pool or section of the bed, if they have accumulated a large amount of loamy material. In the risk group, there are also territories where all conditions for its accumulation are created, and certain areas of watering. These centers have their own classification. There are potholes, incisions and places of dispersed formation of streams. The area of ​​dispersed mudflow is considered to be steep naked areas, in which a large number of strongly destroyed rocks accumulated. Such a focus has a branched and dense network of furrows. Directly in them is the process of microsel formation and the formation of weathering products. Then all these elements are combined into a single channel.

Lacrimal mudflow

This phenomenon is a linearThe formation that cuts the forested, turfed and rocky slopes. They are usually composed of a thin weathering crust. Such ruts are characterized by a small depth and length. The angle of its bottom is more than 15 degrees.

The cut

This phenomenon is a powerfuleducation, which was developed in an array of ancient moraine deposits. Predominantly enters the general part of the sharp bends of the slope. In addition, similar incisions often occur on such types of relief as: avalanche, volcanic, landslide and accumulative. The size of mudflows significantly exceeds the potholes. Their longitudinal profiles also differ. At the embankments they have more smooth outlines than in the ruts. The maximum depth of the first can exceed 100 meters. The area of ​​catchments of this type can reach 60 kilometers, while the volume of excavated soil in one flow is 6 million cubic meters.

Ways of protection

Sel (photo stream is presented in the article) possessesa huge destructive effect. To combat them, special structures are built and measures are taken to fix the plant and soil cover. The choice of the method of protection is based on the definition of the boundaries of the mudflow basin. Ideally, preventive measures should stop and weaken its action even at the very beginning of the flow initiation. Silviculture on the territory of hazardous areas is considered the most radical method. This technique is capable of dividing the total flow into separate jets, reducing the total mass of water and regulating the flow. In the danger zone, it is necessary to increase the stability of the slopes, and also to intercept and remove mudflows by means of earthen ramparts and upland ditches. The most effective use of dams in the channels. They are structures of concrete and stone, whose task is to delay part of the solid flow materials. The dams are intended to guide the village to a less prone shore. Also the effective way of protection is the construction of guide dams. They are able to direct the flow in the right direction and significantly weaken its effect.