What is mudflowstone and what is a mudslide

The flood of water should be made into mud, water, sub-body, road, flowing soil, into the main road, water and stone, and the sand and gravel are rain, mountain stones, floods, mud, rolling through the water, flowing more water, and flowing rivers and sand.

Mudslides are special torrents that carry a large amount of sediment and rocks due to landslides caused by heavy rains, heavy snowfall or other natural disasters in mountainous areas or other ravines and areas with steep terrain. Debris flow has the characteristics of suddenness, fast flow rate, large flow rate, large material capacity and strong destructive power.

The whole process of debris flow is generally only a few hours, and the short is only a few minutes, which is a kind of natural disaster that is widely distributed in some areas with special topography and geomorphological conditions in various countries around the world. This is a mixed flow of soil, water and air between the sediment-carrying water flow and the landslide triggered by heavy rainfall, melting ice and snow and other water sources on the mountain valley or mountain slope.

On the question of what is a mudslide, I would like to say that a mudslide is a special torrent that carries a large amount of solid material such as sand, rocks and boulders on a valley or mountain slope due to precipitation (heavy rainfall, glaciers, snowmelt water). The process of water and sand collection is very complex, and it is the product of the comprehensive action of various natural and/or human factors.

Debris flow has the characteristics of suddenness, fast flow rate, large flow rate, large material capacity and strong destructive power. Mudslides often wash away transportation facilities such as roads, railways, and even villages and towns, causing huge losses.

Debris flow is a torrent formed by heavy rain and flood to saturate and dilute the soft soil mountain containing sand and gravel, and its area, volume and flow are large, while landslide is a small area of diluted soil mountain, and the typical debris flow is composed of thick mud suspended with coarse solid debris and rich in silt and clay.

Under appropriate topographic conditions, a large amount of water soaks the solid accumulation material in the flowing water hillside or ditch bed, reducing its stability, and the solid accumulation material saturated with water moves under its own gravity, forming a debris flow. Mudslides are a catastrophic geological phenomenon. Usually mudslides erupt suddenly and violently, and can carry huge rocks.

Positive tremor is extremely destructive because of its high speed and powerful energy.

The whole process of debris flow is generally only a few hours, and the short is only a few minutes, which is a kind of natural disaster widely distributed in some areas with special topography and geomorphological conditions in various countries around the world. This is a mixed flow of soil, water and air between sand-carrying water flow and landslide on the mountain valley or mountain slope, which is triggered by water sources such as heavy rain and melting ice and snow, and contains a large amount of sediment and stones.

Mudslides are mostly accompanied by flooding in mountainous areas. The difference between it and the general flood is that the torrent contains a sufficient amount of solid debris such as sediment and stone, and its volume content is at least 15% and up to about 80%, so it is more destructive than the flood.

The formation of debris flow must meet the following three conditions at the same time: steep topography that is convenient for water collection and material collection; abundant loose matter; There is a large amount of water in a short period of time.

1. Topography and geomorphological conditions: the terrain has high mountains and deep ravines, steep terrain, large longitudinal slopes of the ditch bed, and the form of the watershed is convenient for water flow. In terms of landform, the landform of debris flow can generally be divided into three parts: formation area, circulation area and accumulation area.

The topography of the upstream formation area is mostly surrounded by mountains on three sides, a scoop or funnel shape with an outlet on one side, the terrain is relatively open, the surrounding mountains are high and steep, the mountains are broken, and the vegetation growth is poor, which is conducive to the concentration of water and detrital materials. The topography of the middle reaches of the circulation area is mostly narrow and steep canyons, and the longitudinal slope of the valley bed is large, so that the debris flow can be rapid and straight. The topography of the downstream accumulation area is an open and flat piedmont plain or river valley terrace, which makes the debris have a place to accumulate.

2. Loose material conditions: debris flows often occur in areas with complex geological structures, developed fault folds, strong neotectonic activities, and high intensity. The fragmentation of surface rock layers, the development of undesirable geological phenomena such as landslides, collapses, and staggered falls provide abundant solid materials for the formation of debris flows. In addition, the rock formation structure is loose and weak, easy to weather, joints are developed, or the soft and hard layered areas are susceptible to damage, and can also provide rich debris for debris flows**; Some human engineering economic activities, such as soil erosion caused by deforestation, mining, quarrying and slag, etc., often also provide a large amount of material for debris flows**.

Ice and snow meltwater and reservoir (pool) outburst water bodies. The main sources of debris flow in China are heavy rain and long-term continuous rainfall.

Debris flow is a special torrent in a mountainous valley that is triggered by heavy rain, ice and snow melt and other water sources, and contains a large amount of sediment and stones. It is often characterized by sudden outbursts, with turbid fluids rushing forward and back along steep ravines, rushing and roaring down, shaking the ground and thundering valleys. In a very short period of time, a large amount of sediment and stones are washed out of the ditch, and they are rampaged and accumulated in a wide accumulation area, which often causes major harm to human life and property.

Debris flow can be divided into three categories according to its material composition: it is called debris flow composed of a large number of cohesive soil and sand and stones of different particle sizes; Mainly cohesive soil, containing a small amount of sand, stones, high viscosity, thick mud called mudflow; It is composed of water and sand and stones of different sizes, which is called a water and stone flow. Debris flows can be divided into two categories according to their state of matter:

The first is cohesive debris flow, which contains a large amount of cohesive soil or mudflow. It is characterized by high viscosity, with a solid substance accounting for 40 60 and a maximum of 80.

The water in it is not a transport medium, but a constituent substance, with a large consistency, the stones are suspended, the outbreak is sudden, the duration is short, and the destructive power is large. The second is dilute debris flow, with water as the main component, the content of cohesive soil is small, and the solid matter accounts for 10 40, which has great dispersion. Water is the transport medium, and the stone moves forward in a rolling or jumping way, which has a strong downward cutting effect.

Its accumulation is fan-like scattered in the accumulation area, and it looks like a "stone sea" after stopping.

The above are the two most common classifications in China. In addition to this, there are several ways to classify it. For example, according to the causes of debris flows, there are:

Shuichuan-type debris flow, rainfall-type debris flow; According to the size of the debris flow basin, there are large debris flows, medium debris flows and small debris flows; According to the development stage of debris flow, there are debris flow in the development period, debris flow in the vigorous period and debris flow in the decline period.

There are three conditions that must be met for the formation of a debris flow: There is abundant and loose solid matter in the watershed. The valley slope in the basin is steep and the ditch bed ratio is large.

In the middle and upper reaches of the valley, there are torrential rains, floods, ice and snow meltwater, and lakes and reservoirs bursting, which provide sufficient water sources. Debris flows are easy to form in mountainous areas with developed fault structures, frequent occurrence, concentrated precipitation, and serious soil erosion, as well as in alpine areas where ancient glaciers are developed and modern glaciers are active. In terms of time, debris flows mostly occur in rainy and rainy years after several years of drought, or after unreasonable human exploitation of mountains, or in years when the climate warms, glaciers decline, snow cover melts, and permafrost thaws.

Debris flow is a high-concentration solid and liquid two-phase flow. The solid substance contains 30 80, and the bulk weight of the fluid is tons 3. The quantity, composition, and recharge mode of solid matter determine the nature, type, and scale of the debris flow.

There are many classifications of debris flows: according to the formation characteristics, they can be divided into glacial type and rainfall type debris flow. According to the valley morphology, it can be divided into valley type and hillside type debris flow.

According to the material composition, it is divided into debris flow, mudflow, and waterslide. According to the structure-rheological classification, it can be divided into dilute debris flow (bulk weight tonn3, sand content 800 1200 kgm3), with strong turbulence; Sticky debris flow (bulk weight tonnes3, sediment content 1600 kgm3).

Laminar flow is dominant; Transitional debris flows, somewhere in between. According to the scale, it can be divided into small (100,000 cubic meters of primary material), medium (10.5 million cubic meters of primary material), large (501,000,000 cubic meters of primary material) and extra-large (1,000,000 cubic meters of primary material).